078 of 2021 - 2020 Salt Lake City Street Lighting Master Plan78
14th December
Amy Fowler (Jan 10, 2022 09:38 MST)
Jan 10, 2022
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Cindy Trishman (Jan 19, 2022 14:52 MST)
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Rusty Vetter (Dec 21, 2021 14:09 MST)
Dec 21, 2021
Erin Mendenhall (Jan 13, 2022 11:32 MST)
Cindy Trishman (Jan 19, 2022 14:52 MST)
Ordinance 78 of 2021 - 2020 Salt Lake City
Street Lighting Master Plan
Final Audit Report 2022-01-19
Created:2021-12-21
By:Thais Stewart (thais.stewart@slcgov.com)
Status:Signed
Transaction ID:CBJCHBCAABAA0d9sT7_q44F-3k3rQiPEMCZeHSd1vodw
"Ordinance 78 of 2021 - 2020 Salt Lake City Street Lighting Mas
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SALT LAKE CITY, UT
Street Lighting Master Plan
VOLUME 1 - MASTER PLAN
JUNE 2020
3
INTRODUCTION TO THE PLANNING PROCESS..........7
EXECUTIVE SUMMARY .............................................9
Current System Evaluation ................................9
Policy Statements ................................................10
Implementation Steps ..........................................11
SYSTEM BACKGROUND, HISTORY ..........................13
CURRENT SYSTEM EVALUATION ..........................16
CURRENT LIGHTING POLICIES AND PROGRAMS ...16
2006 Street Lighting Master Plan .............16
Special Improvement Districts ...................16
Private Lighting Program ..............................16
EXISTING LIGHTING CONDITIONS ........................17
Process ...................................................................17
CITY PLANNING GUIDANCE .................................19
Plan Salt Lake ......................................................19
Neighborhood Master Plans ......................20
Lighting Levels & Gaps ..................................24
Evaluation by Community/District ..........25
PLAN GUIDEPOSTS ..................................................27
Safety .........................................................................27
Character ..................................................................27
Responsibility .........................................................27
Equity .........................................................................28
STREET LIGHTING BASICS OVERVIEW ..................29
SYSTEMWIDE CONSIDERATIONS ............................29
Health and Wellbeing..........................................29
Wildlife Impacts .....................................................29
LIGHTING CHARACTERISTICS ..................................29
Appropriate Light Levels ..................................29
Glare Reduction .....................................................31
Uniformity vs. Contrast ......................................32
Adaptation ...............................................................33
Color Rendering and Nighttime
Visibility ....................................................................34
Color Temperature and Nighttime
Visibility .....................................................................35
Light Trespass ........................................................36
Light Pollution ........................................................37
COSTS AND IMPLEMENTATION ................................38
Initial Costs ..............................................................38
Long Term Life Cycle Costs .............................38
Maintenance ............................................................39
Energy ........................................................................39
Standardization .....................................................39
STREET LIGHTING PLAN..........................................40
Lighting Improvement Strategies ...........40
Purpose ................................................................40
Lighting Layout Strategies .........................40
Street Lighting Only ........................................42
Street and Pedestrian Lighting .................43
Pedestrian Lighting Only .............................44 TABLE OF CONTENTSTABLE OF CONTENTS
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SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
Special Lighting Districts ............................45
Intersection Lighting .....................................46
Vertical Illumination in Crosswalks ..........47
Bus Stop ..............................................................48
Environmentally Protected Areas ...........48
IMPLEMENTATION OF UPGRADED LIGHTING .......48
Street Lighting Equipment and
Technology ........................................................50
Lighting Improvements
Complexity & Cost ...........................................52
Minimal 1-for-1 Replacements .....................52
Supplemental .....................................................52
Comprehensive .................................................52
PRIORITIZING LIGHTING IMPROVEMENTS ...........52
Areas Underserved by
Street Lighting ...................................................53
High Priority Conflict Areas ........................53
1-for-1 Lighting Improvements ...................57
APPENDIX ..........................................................59
A. Glossary of Lighting Terms ........................59
B. Committee Meeting Notes ..........................61
C. Existing Conditions Report
Presentation ......................................................67
D. Nocturnal Infrastructure for
Ecological Health ...........................................89
E. Luminaire Submittal Forms ......................123
5
FIGURE 1: Site Evaluation Map ...................................10
FIGURE 2: Neighborhood
Master Plans Map – 2017 ...........................................20
FIGURE 3: Street Light Density Map .......................24
FIGURE 4: Community Character Map ..................25
FIGURE 5: Appropriate Light Level ..........................29
FIGURE 6: Glare Reduction ...........................................31
FIGURE 7: Uniformity Vs. Glare ..................................32
FIGURE 8: Adaptation ....................................................33
FIGURE 9: Color Rendering ........................................34
FIGURE 10: Color Temperature ..................................35
FIGURE 11: Light Trespass .............................................36
FIGURE 12: Light Pollution ............................................37
FIGURE 13: Initial Costs: Guidepost Synergy &
Balance ...............................................................................38
FIGURE 14: Energy ..........................................................39
FIGURE 15: Street Lighting Warrants Matrix .........41
FIGURE 16: Street Lighting Only
Cross Section ..................................................................42
FIGURE 17: Street & Pedestrian
Lighting Cross Section...............................................43
FIGURE 18: Pedestrian Only
Lighting Cross Section...............................................44
FIGURE 19: Cactus Lights Cross Section ..............45
FIGURE 20: Intersection Lighting Plan ..................46
FIGURE 21: Crosswalk Lighting ..................................47
FIGURE 22: School Locations .....................................53
FIGURE 23: Bus Stop Locations ................................54
FIGURE 24: Transit Stations .........................................55
FIGURE 25: Neighborhood Byways .........................56
TABLE OF FIGURES TABLE OF TABLES
TABLE 1: Plan Policy Statement Comparison
2006-2020 ........................................................................14
TABLE 2: Street and Sidewalk Lighting
Conditions Council District Locations ..................17
TABLE 3: Street and Sidewalk
Existing Lighting Ratings ............................................19
TABLE 4: Street Lighting Policy
and Implementation Items .........................................21
TABLE 5: Lighting Layout Strategy
By Land Use ....................................................................49
TABLE 6: Recommended Luminaries
By Land Use ......................................................................51
6
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
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7
The 2020 Street Lighting Master Plan was
developed with the input and guidance of two
committees and reviewed by a Stakeholders
group. The Advisory Committee included
representatives from:
• Each City Council District
• Department of Public Utilities
• Mayor’s Office
The Advisory Committee met six times during
the process to provide guidance on policy
issues:
• Street Lighting Site Tour & Surveys
(November 5, 2018)
• Street Lighting 101 (April 3, 2019)
• Visioning Session (April 25, 2019)
• Council & Mayor’s Office Briefing (May 24,
2019)
• Stakeholder Update (July 30, 2019)
• 50% Progress Update (January 8, 2020)
The Advisory Committee created a list of
lighting concerns and priorities for each district
across the City as well as provided guidance on
the City’s street lighting vision and guideposts.
Notes from their meetings are found in the
appendix.
The second committee was the Technical
Committee with representatives from the
following City departments:
• Police
• Fire
• Sustainability
• Engineering
• Planning
• Urban Forestry
Technical Committee members represented
the interests of their departments in the master
planning process. They also participated in the
street lighting site tour. Technical Committee
input also contributed to the vision and guiding
principles used in the planning process. Notes
from their meetings are found in the appendix.
The current system evaluation and the plan
vision and guideposts were reviewed by
stakeholder groups on July 29-30, 2019 with
representatives from:
• Education
• Business
• Transit/Multi-modal transportation
• Environmental
Stakeholder input is included in this draft plan.
This draft plan is submitted to the City Council
for review, possible revision, and adoption.
Following adoption, the Department of Public
Utilities will hold a series of community
meetings to familiarize residents, developers,
and stakeholders on the policies, standards and
processes included in this plan.INTRODUCTION TO THE PLANNING PROCESSINTRODUCTION TO THE PLANNING PROCESS
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SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
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EXECUTIVE SUMMARYEXECUTIVE SUMMARY
Salt Lake City requested an evaluation of
existing street lighting conditions and a
master plan to aid in transitioning all Salt
Lake City-owned street lighting from a high
pressure sodium system to an LED system, a
process begun in 2013. In addition, the master
plan identifies methods to improve visibility
and aesthetics while reducing energy and
maintenance through a lighting control system.
The master plan identifies new street lighting
standards for retrofit and new construction.
The goal of this document is to provide Salt
Lake City with a consistent approach for
street and pedestrian lighting that creates
a quality nighttime visual experience. Street
and pedestrian lighting plays a key role in
how people experience the city in which they
live, work, and play. Lighting helps drivers
and pedestrians understand the streetscape
through visual cues and heightened awareness
of their environment. Providing good visibility
with lighting increases comfort levels and
encourages use of public streets and spaces.
The plan identifies a strategy that balances
safety, character, responsibility, and equity
using a series of guideposts for evaluating the
lit environment and the technical elements of a
streetlighting system.
CURRENT SYSTEM EVALUATION
The Advisory and Technical Committees along
with the consulting team surveyed seventeen
locations in the city. In addition, the consulting
team conducted nighttime surveys and
measured the light levels along primary arterial,
minor arterial, collector and local streets.
Survey sites were selected in each Council
District to represent a variety of existing
lighting conditions throughout the city. Based
on the survey and evaluations, the consulting
team created an Existing Conditions Report
(Appendix C) to aid the city in understanding
relationship of visual perception to measured
light levels.
The consulting team categorized each survey
site according to IES standards acceptability
light level, lamp wattage, street type, luminaire
spacing and measured lighting levels. The four
levels of acceptability are:
• Excellent. the survey sites identified as
“Excellent” received the highest scores from
the Advisory and Technical Committees,
indicating excellent visibility, appropriate
light levels, low glare, uniformity and good
color.
• Acceptable. the street meets lighting
standards based on street classification
and existing luminaire spacing. Block faces
categorized as “Acceptable” require only
LED retrofit.
• Moderate. the street does not meet lighting
standards based on street classification
and existing luminaire spacing. Block faces
categorized as “Moderate” require minor
improvements to address relatively small
dark spaces between poles as well as LED
retrofit.
• Poor. the street has very low or no street
lighting. Block faces categorized as “Poor”
require significant investment in new lighting
and electrical infrastructure to meet lighting
standards.
As seen in Figure 1, of the sites surveyed, 17
percent are categorized as Excellent, 35 percent
are Acceptable, 24 percent are Moderate and
24 percent are Poor.
The following policy statements are intended
to guide the approach to addressing identified
needs and gaps in the City’s current street
lighting as well as apply to future changes in
the system.
10
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1EXECUTIVE SUMMARYPOLICY STATEMENTS
Based on the application of planning guideposts
and input of the steering and technical
committees, the master plan implements the
following major policies:
• Street lighting will enhance safety through
the implementation of industry recognized
standards.
• Street lighting standards include allowances
to encourage dimming strategies relating to
pedestrian activity, wildlife and dark skies
lighting.
• Street lighting will minimize the obtrusive
effects of light at night resulting from light
trespass, light pollution, and glare through
the selection and placement of appropriate
poles, fixtures, light type, and light levels.
• Provide pedestrian lighting in accordance
with neighborhood plans and in accordance
with the typologies in this plan.
• Provide street and pedestrian lighting that
minimizes impacts to sensitive wildlife species.
• Select fixture types to provide dark skies
protection.
• Implementation based on neighborhood
and community input to determine pole,
fixture type, maximum and minimum light
level, and the implementation of adaptive
dimming applications when appropriate.
The standards and implementation strategies
to achieve Salt Lake City’s major street lighting
policies are included in this plan. Salt Lake City
utilizes IES standards with allowances to respond
to pedestrian, wildlife, and dark skies priorities.
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
SLC Public Utilities
Excellent Site
Acceptable Site
Moderate Site
Poor Site
1000 North
I-80
Redwood RoadSouth Temple
400 South
900 South
1300 South
1700 South
Sunnyside Avenue
Footh
i
l
l
D
r
ive
1300 East700 EastState StreetI-15900 West1
2
Figure 1: Site Evaluation Map
Site # Site Name Street
Classification
Existing
Lighting
Sterling & American
Beauty Dr. Local / Residential Excellent
Riverside Park
& 600 North Arterial / Park Acceptable
Redwood Rd.
& South Temple Collector / Industrial Poor
700 South
& Post Street Local / Residential Poor
500 West & Dalton
Ave.Arterial / Residential Acceptable
Glendale Dr. &
Navajo St.
Collector / Residential
/ Commercial Moderate
J St. & 2nd Ave.Local / Residential Poor
800 East & South
Temple Arterial / Commercial Excellent
200 South & Floral St.Arterial / Commercial Excellent
650 South & Main St.Arterial / Commercial Acceptable
700 East & Harrison
Ave.Arterial / Residential Poor
900 East & 900 South Arterial / Commercial Acceptable
Layton Ave. & West
Temple Local / Residential Moderate
1500 South & Yale Collector / Residential Acceptable
19th East & Sunnyside Arterial / Residential /
Commercial Moderate
1400 East & Redando Local / Residential Moderate
1000 East & 2100
South Arterial / Commercial Acceptable
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
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IMPLEMENTATION STEPS
Funding and prioritization are the key drivers
in implementation of the policies, standards,
and strategies in this plan. Road classification
and adjacent land use are the driving factors
in selection of street lighting type, spacing and
light levels. There are neighborhoods and high
conflict areas of the City that are recommended
for priority implementation.
In all cases, the initial step in implementation
is coordination with the community and
immediate neighborhood to ensure that the
solution identified meets resident, business
owner and user needs.
Implementation recommendations prioritize
the following:
• PRIORITY ONE:
- Neighborhoods currently underserved
for street and/or pedestrian lighting
based on adjacent land uses.
- High conflict areas including:
• School Zones
• Bus Stops
• Transit Stations
• Neighborhood Byways
• PRIORITY TWO:
- Areas with non-compliant existing
streetlighting (luminaire, light source or
pole spacing)
• ONGOING:
- Replacement of lamps with LED
luminaires on regular maintenance
schedule as appropriate
- Replacement of non-compliant street
lighting in areas of ecological sensitivity
- Installation of dimming capability at
neighborhood request
- New development or redevelopment
proposals
STEP ONE:
• Identify high conflict areas in the City
• Review the current lighting map to identify
underserved neighborhoods and high
conflict areas
• Respond to request from community or
neighborhood for lighting change
STEP TWO:
• Contact community and neighborhood
representatives to identify priorities and
review options according to the matrix
• Identify neighborhood-preferred option
according to the matrix
STEP THREE:
• Estimate cost of preferred option
• Seek funding approval
STEP FOUR:
• Design, schedule and implement preferred
option
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SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
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SYSTEM BACKGROUND, HISTORYSalt Lake City was the fifth city in the United
States to have electric lights. By 1887,
streetlights were operating on Main Street and
along First and Second South Streets. The City’s
first systematic plan for locating streetlights
was adopted in 1908. The most recent previous
update to Salt Lake City’s streetlighting plan
was completed in 2006 when the system was
operated and maintained by the Salt Lake
City Transportation Department within the
Community Development Department.
In 2012 responsibility for streetlight policy,
operations and maintenance was transferred
to the Street Lights Department within the
Department of Public Utilities. This move
coincided with the implementation of a monthly
user included in business and residential
public utility bills along with drinking water,
wastewater, stormwater and sanitation services.
The Department manages and maintains
more than 15,500 streetlights in Salt Lake
City and has overseen the conversion of the
City’s inventory to high-energy efficiency LED
lamps with a target completion date of 2021.
The Department placed the conversion to LED
streetlights on hold in 2018 to allow this Street
Lighting Master Plan to guide the conversion of
the remaining streetlights.
As part of the Street Light Master Plan
update, the current system was reviewed and
recommendations for changes to the system
and updates to Salt Lake City’s streetlighting
policies were developed. In addition, guidance
for installation of new lighting in newly
developed areas as well as changes to existing
areas is included in Volume 2 - Technical
Guidance and Implementation Plan.
SYSTEM BACKGROUND, HISTORY
14
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1SYSTEM BACKGROUND, HISTORYThe 2012 LED conversion project implements
the 2006 Master Plan policy statements. In the
interim there have been lighting technology
advances, revisions in standards and a new
awareness of the impact of exterior lighting
on human and environmental health as well
as attention to dark skies initiatives. This plan
updates Salt Lake City’s policies and standards
to reflect these advances and changes.
Table 1 provides a comparison of the 2006 Street
Lighting Master Plan policy statements and
revisions and additions to those policy statements
recommended in this update to the Plan.
TABLE 1 - PLAN POLICY STATEMENT COMPARISON 2006 TO 2020
2006 PLAN POLICY STATEMENT 2020 PLAN PRELIMINARY RECOMMENDED
POLICY REVISIONS/ADDITIONS
Salt Lake City lighting standards are based on IES
recommendations
Revise policy: Salt Lake City lighting standards are
based on IES recommendations with allowances
for adaptive standards that encourage dimming
strategies relating to pedestrian activity, community
engagement, wildlife and dark skies lighting.
Lighting level and design will be upgraded to
current standards as lights are replaced and new
lights are installed
No Change
All newly installed utility lines shall be underground No Change
When practical installation of underground
conduit for utility lines shall be included in road
reconstruction projects
No Change
Only dedicated publicly owned streets are eligible
for street lighting funded by the City
No Change (Possible future revision for public
alleyways. Discussion with transportation and
planning.)
Placement of street light poles shall meet safety
standards including lateral clearance requirements No Change
Energy efficient lights shall be used for new and
replacement lighting.
Revise policy to balance energy efficiency with
human/environmental health. Process to identify
areas better suited to amber LEDs primarily for
open space and wildlife.
All new streetlights must meet, at a minimum,
the “dark sky semi-cutoff” standard with the
exception that all new “shoe box” or “cobra head”
style streetlights must meet the “dark sky cutoff”
standard.
Provide street and pedestrian lighting that reduces
the obtrusive effects of light at night, including
light trespass that intrudes on private property,
light pollution to preserve dark skies, and glare that
reduces visibility and annoys drivers, pedestrians
and residents.
15
SYSTEM BACKGROUND, HISTORY2006 PLAN POLICY STATEMENT 2020 PLAN PRELIMINARY RECOMMENDED
POLICY REVISIONS/ADDITIONS
Lighting appropriate for conditions shall insure
uniform and safe lighting on major streets and
commercial district streets
No change to the policy. Standards relating to
decorative poles and fixtures to be updated.
Standards relating to private lighting standards in
the Northwest Quadrant to be developed.
Public input may be sought regarding fixture and
pole type in commercial areas
Additional public input may be sought to determine
maximum and minimum light levels on residential
collector and local streets for adaptive dimming
application.
Residential neighborhoods may adopt a decorative
street light fixture and pole from the approved
list on non-major streets in accordance with a
neighborhood master plan
No Change
All new and replacement lighting shall be from the
approved list developed by the City Transportation
Engineer
No change to the policy (except departmental
designation.) Possible changes to the approved list.
It is the policy of the Salt Lake City Transportation
Department to support the use of Crime Prevention
Through Environmental Design principles in the
design and operation of street lighting within Salt
Lake City.
No Change (except departmental designation)
It is the policy of the Salt Lake City Transportation
Department to support the use of banners on street
light poles to enhance a sense of community and
contribute to traffic calming.
No Change (except departmental designation)
It is the policy of the Salt Lake City Transportation
Department to coordinate the location of new street
lights with the Salt Lake City Forester and, in turn,
coordinate on the planting of new trees such that
both are compatible in providing desired benefits
to the neighborhood.
No Change (except departmental designation)
Provide street and pedestrian lighting that
minimizes impacts to sensitive wildlife species.
Pedestrian scale lights (typically 12’ to 15’ mounting
height) are on any streets where streetlighting
alone does not effectively illuminate the sidewalk
due to shadowing from trees, or the location of
the sidewalk in relation to the street. Pedestrian
scale lights on local residential streets to minimize
light trespass and create more pedestrian friendly
streets, and in commercial areas to encourage
pedestrian usage.
16
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1CURRENT SYSTEM EVALUATION2006 STREET LIGHTING MASTER PLAN
Salt Lake City last published a Street Lighting
Master Plan in 2006. While most of the lighting
principles and goals from 2006 are continued
in this master plan, technical advancements in
lighting equipment have allowed improvements
to be made in the control and application of
light. The 2006 Master Plan pushed the lighting
in the city to be safer and more pedestrian
friendly while minimizing light pollution
and light trespass. It encouraged the use of
decorative luminaires to match the character
of the neighborhood or enhance downtown
commercial districts. These principles of
safety and character established in 2006
are guideposts to this Master Plan and will
be continued in the lighting strategies and
principles throughout the City. The new Master
Plan is striving to create a more pedestrian
centric city where auto-alternate solutions can
be safer and more widely used. The new plan is
still encouraging the use of decorative luminaire
options in certain areas throughout the city but
is requiring enhanced control of light to further
minimize light pollution and light trespass.
Since 2006 advances in LED technology have
allowed for significant increases in control of
light distribution and color. The new Master
Plan takes advantage of these advances to
recommend the best lighting solutions for each
block based on adjacent land use, pedestrian
volume, and environmentally sensitive areas.
The new plan sets luminaire criteria for lumen
output, distribution, and color temperature
to ensure appropriate and effective lighting
that aims to reduce light pollution and light
trespass. Additionally, this master plan provides
guidance on lighting controls to help the City
establish a citywide wireless control network
that will assist in more efficient management
and control of streetlights.
SPECIAL IMPROVEMENT DISTRICTS
Certain areas within the City have decorative
lighting as a replacement or supplement
to the baseline lighting as part of a Special
Improvement District. In these residential or
commercial areas, the property managers agree
to pay the capital costs for new or replacement
lighting plus 75% of the ongoing operating
and maintenance costs. Special Improvement
Districts include the Cactus Poles in the
downtown commercial area and the pedestrian
post top lights in the Rose Park Neighborhood.
PRIVATE LIGHTING PROGRAM
In 1995 Salt Lake City started the Private
Lighting program, allowing residents to
purchase, install and maintain streetlights on
their blocks. The program is designed to allow
the residents of Salt Lake to choose the poles
and luminaires that are installed on their block
while still ensuring sufficient lighting in the
neighborhood. Each block is required to have
at least six lights, including at least one at each
intersection. Lights are owned by the residents
and are connected to home of the owner with
underground wiring. Residents can apply for
a one-time grant from the city to help offset
costs. Depending on funding, the grant can be
up to $5,000 per block, but must be matched
by the neighborhood, dollar for dollar. The City
must approve all lighting equipment and will
inspect all installations.
CURRENT SYSTEM EVALUATION
17
CURRENT SYSTEM EVALUATIONEXISTING LIGHTING CONDITIONS
PROCESS
The Advisory and Technical Committees surveyed seventeen sites in different areas of the city.
The sites were selected based on street type, arterial, collector, or residential, and on their
surrounding environments in the city, industrial, commercial, transit or residential. The diversity of
the sites provide an understanding of the lighting and environmental conditions found in different
neighborhoods and along different transportation corridors throughout the city. Only streets,
sidewalks and pedestrian paths in the Public Right of Way were evaluated. Privately owned lighting
was not included. The survey asked participants about the street and sidewalk lighting conditions
at each of the following seventeen sites.
TABLE 2: STREET AND SIDEWALK LIGHTING CONDITIONS COUNCIL DISTRICT LOCATIONS
LOCATION CLASSIFICATION COUNCIL DISTRICT
Sterling Drive & American
Beauty Drive
Local/Residential 1
700 North & Riverside Park Arterial/Park 1
Redwood Road & South Temple Collector/Industrial 1 & 2 Boundary
700 South & Post Street Local/Residential 2
900 West & Dalton Avenue Arterial/Residential 2
Glendale Drive & Navajo St.Collector/Residential/
Commercial
2
J St. & 1st Avenue Local/Residential 3
800 East South Temple Arterial/Commercial 3 & 4 Boundary
200 South Floral Street Arterial/Commercial 4
650 South Main Street Arterial/Commercial 4
700 East Harrison Avenue Arterial/Residential 5
900 South & 900 East Arterial/Commercial 5
Layton Ave. & West Temple Local/Residential 5
1500 East & Yale Avenue Collector/Residential 6
1900 East & Sunnyside Arterial/Residential/Commercial 6
1400 East & Redondo Local/Residential 7
1000 East & 2100 South Arterial/Commercial 7
The survey included the following statements to which participants indicated their level of
agreement by ranking their response between Strongly Agree and Strongly Disagree.
• It would be safe to walk here alone during daylight hours.
• It would be safe to walk here alone during darkness hours.
• The light is uneven (patchy).
• The light sources are glaring.
• The lighting is poorly matched to the neighborhood.
18
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1CURRENT SYSTEM EVALUATIONTo supplement survey responses, High Dynamic
Range photographs were taken and horizontal
and vertical illuminance light measurements
recorded for the sidewalks and luminance
measurements taken along the roadway at
each site. The measurements were compared to
recommended levels in the IES Recommended
Practice for Roadway Lighting (RP-8-18).
Based on survey results, HDR photographic
evidence and light measurements, the
consulting team rated lighting at each site as
Excellent, Acceptable, Moderate or Poor.
Excellent rated lighting is sufficient and
appropriate on the roadway, provides adequate
vertical illumination to allow for object detection
and facial recognition. Excellent lighting is
relatively uniform, free of direct glare and
properly illuminates the roadway and sidewalk.
Acceptable rated lighting is comfortable. In
some cases, such as residential areas, the light
level might be lower than the IES Recommended
Practice but the lack of glare and shadowing
from surrounding landscaping, along with
some surrounding surface brightness, creates
a comfortable nighttime environment without
light trespass.
Moderate rated lighting does not provide enough
light on the roadway or on the sidewalk. The color
of the light may be inconsistent, and the presence
of glare may result in an uncomfortable space.
Some of these sites were shadowed due to trees,
and lighting was not appropriately spaced.
Poor rated lighting occurs when the luminaires
are spaced too far apart to provide adequate light
levels and uniformity or there are no luminaires on
the street at all. These sites included residential
areas without sufficient light, industrial sites and
an arterial road where lights were malfunctioning.
Of the 17 sites evaluated, three were excellent.
Of the excellent sites one is a local residential
street and two are arterial commercial streets.
Six sites were ranked good. Of the good sites
five are arterials, one adjacent to a park, one
in a residential area, three in commercial areas,
and one is a collector in a residential area. Four
sites were moderate. Of the moderate sites two
are local residential streets, one is a collector in a
residential/commercial area, and one is an arterial
in a residential/commercial area. Four sites were
rated poor. Of the poor sites one is a collector in
an industrial area, two are local residential areas
and one is an arterial residential area.
19
CURRENT SYSTEM EVALUATIONTable 3: Street and Sidewalk Existing Lighting Ratings
SITE #CLASSIFICATION EXISTING LIGHTING RATING
1 Sterling Drive & American
Beauty Drive
Local/Residential Excellent
2 700 North & Riverside Park Arterial/Park Acceptable
3 Redwood Road & South Temple Collector/Industrial Poor
4 700 South & Post Street Local/Residential Poor
5 900 West & Dalton Avenue Arterial/Residential Acceptable
6 Glendale Drive & Navajo St.Collector/Residential/ Commercial Moderate
7 J St. & 1st Avenue Local/Residential Poor
8 800 East South Temple Arterial/Commercial Excellent
9 200 South Floral Street Arterial/Commercial Excellent
10 650 South Main Street Arterial/Commercial Acceptable
11 700 East Harrison Avenue Arterial/Residential Poor
12 900 South & 900 East Arterial/Commercial Acceptable
13 Layton Ave. & West Temple Local/Residential Moderate
14 1500 East & Yale Avenue Collector/Residential Acceptable
15 1900 East & Sunnyside Arterial/Residential/Commercial Moderate
16 1400 East & Redondo Local/Residential Moderate
17 1000 East & 2100 South Arterial/Commercial Acceptable
The ratings provide an understanding of the
variety of nighttime environments in different
areas of the city and guided the development of
improvement options. Each option focuses on
improving light levels and uniformity, reducing
glare, and enhancing wayfinding.
The full report including site specific metrics can
be found in Appendix C.
CITY PLANNING GUIDANCE
PLAN SALT LAKE
In Plan Salt Lake adopted in 2015 the community
identified 13 guiding principles. Although not
always specifically mentioned, high quality street
lighting can contribute to achievement of most of
the guiding principles.
Six of the principles can be directly affected
through the implementation of quality street
lighting:
1/Neighborhoods that provide a safe environment,
opportunity for social interaction, and services
needed for the wellbeing of the community
therein.
4/A transportation and mobility network
that is safe, accessible, reliable, affordable,
and sustainable, providing real choices and
connecting people with places.
6/Minimize our impact on the natural environment.
7/Protecting the natural environment while
providing access and opportunities to recreate
and enjoy nature.
20
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1CURRENT SYSTEM EVALUATION8/A beautiful city that is people focused.
13/A local government that is collaborative,
responsive, and transparent.
Plan Salt Lake includes specific initiatives to that
mention street lighting to achieve the Guiding
Principles. These include “Incorporate pedestrian
oriented elements, including street trees,
pedestrian scale lighting, signage, and embedded
art, into our rights-of-way and transportation
networks” as an initiative to create a safe
mobility network. This is a critical initiative to
achieve several other initiatives, including overall
connectivity and safety in the public realm. Plan
Salt Lake also includes an initiative to “promote
and expand the city’s street lighting program
throughout the City” as part of the beautiful city
Guiding Principle. This is also a critical initiative
to achieve several other initiatives, including
reinforcing and preserving neighborhood and
district character and providing a strong sense of
place.
In addition, implementation of this Street Lighting
Master Plan to identify and address current
gaps in service and upgrade overall lighting will
contribute to the fulfillment of several other of
the Guiding Principles.
NEIGHBORHOOD MASTER PLANS
Salt Lake City has completed eleven neighborhood
master plans for the areas of the City represented
on the map in Figure 2.
Figure 2: Neighborhood Master Plans Map - 2017
21
CURRENT SYSTEM EVALUATIONThe master plans date from the 1980s through 2017 with amendments and updates. Street lighting is
mentioned in many of them as a tool to enhance community character and identify the City’s special
lighting district program as a tool for implementation. Several of the plans also identify the installation
of pedestrian level lighting as a community enhancement strategy.
Some plans identified specific policies and implementation measures relating to street lighting as
identified in the table below:
TABLE 4: STREET LIGHTING POLICY AND IMPLEMENTATION ITEMS
COMMUNITY ADOPTION GOAL OR POLICY STATEMENT ACTION OR
IMPLEMENTATION ITEMS
Avenues 1987 None • Streetscape “demonstration project”
to illustrate use of streetscape,
including street lighting, to improve the
neighborhood.
Capitol Hill 1999
Amended
2001
• Coordinate any new
street lighting program in
designated historic districts
with the Historic Landmark
Commission to ensure the
design of the street lights are
compatible with the historic
character and comply with the
historic district regulations.
• Provide a consistent design
theme and increase the
amount of street lighting on
300 West and 400 West.
• Analyze the feasibility and demand for
increasing the amount of street lighting
in areas of the Capitol Hill Community
where needed and determine funding
sources.
• Develop and implement a consistent
lighting and street furniture theme for
the Capitol Hill neighborhood (north of
North Temple).
Central 2002
Amended
2006
• Relate right-of-way designs to
land use patterns.
• Ensure that public streets are
maintained and improved
throughout the Central
Community
• Encourage where appropriate rights-
of-way that have landscaped street
medians, landscaped park strips, street
trees, on-street parking, pedestrian
lighting, and furnishings such as major
arterials.
• Provide consistent neighborhood
design themes for street lighting and
ensure that street lighting is provided
at a pedestrian scale. Coordinate street
lighting in designated historic districts
with the Historic Landmark Commission
to ensure that compatible design and
placement patterns are met.
22
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1CURRENT SYSTEM EVALUATIONDowntown 2016 • Make downtown a unique
destination for visitors.
• A complete pedestrian
network that makes walking
downtown safe, convenient
and comfortable.
• A public realm that is looked
after 24/7.
• A downtown known for its
well-maintained public realm.
• Maintain and refresh existing policies
regarding sidewalk paving materials and
street lighting in districts where these
items have already been established
in this plan or other plans such as the
Street Lighting Master Plan.
• Address pedestrian safety and comfort
issues with regularly planted trees,
shortened crossing distances, tighter
curb radii, hawk or other pedestrian-
activated signals, pedestrian lighting,
and regularly spaced benches and
seating.
• Continue implementation of pedestrian
lighting throughout downtown.
• Maintain the city improvements such as
street lights, seating, and paving.
Westside 2014 • Create a more conducive
environment for
redevelopment at
neighborhood nodes.
• Street lighting should be emphasized
at intersections and be scaled to the
pedestrian level.
23
CURRENT SYSTEM EVALUATIONEast Bench 2017 • Business Districts that
Promote Neighborhood
Identity
• Improve the Street Rights-of-
way to Create Beautiful and
Safe Gateway Corridors
• Dark Sky Friendly Lighting
• Building features, such as height,
placement and materials, as well as
street improvements such as signage,
landscaping, lighting, paving materials,
and pedestrian crossings activate the
individual business districts, create a
distinct identity, create a sense of place,
and help create a more pleasant auto-
pedestrian interface.
• Establishing a gateway should not stop
at creating an entrance feature at the
beginning of the street, but should carry
through the entire length of the corridor
with consistent design treatment, such
as street lighting, street furniture, and
pavement treatments that relate to the
character of each gateway.
• The East Bench is the interface between
the natural and urban environment. As
such the built environment within the
community should respect the natural
surroundings. One particular aspect
of development that can impact both
the natural and human environment
is lighting. In an effort to minimize
disruption to wildlife, impacts on
adjacent property, and the community’s
enjoyment of the night sky, lighting
should:
- Only be on when needed;
- Only light the area that needs it;
- Be no brighter than necessary;
- Minimize blue light emissions; and
- Be fully shielded and pointing
downward.
Northwest 1990 None None
Northwest
Quadrant
2016 • Promote the design of
transportation corridors that
support the natural landscape
• North of I-80, provide a
common Northwest Quadrant
design theme for the public
infrastructure, such as native
landscaping, lighting, bridge
design, signs, etc.
• Use appropriate but minimal levels
of lighting to keep sites darker near
Natural Areas
- Direct lights down and away from
natural habitats.
- Avoid tall street lights that may
negatively impact wildlife habitat.
- Use the minimum number of street
lights necessary for safety.
- Along trails, use lights that only light
the trail and not wildlife habitat.
• Street lighting should use poles and
fixtures that are compatible with the
natural environment.
24
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1CURRENT SYSTEM EVALUATIONIt’s clear from Salt Lake City’s adopted policy statements and implementation priorities in both
citywide and community-level plans that pedestrian level street lighting is an important element for
creating a sense of safety and community.
LIGHTING LEVELS & GAPS
Implementation of Salt Lake City’s current lighting policy, standards, and approach is illustrated in the
streetlight density map in Figure 3.
Key
Lighting Strategies Heat Map
SLC Boundary
Streetlights
Dense
Sparse
Each streetlight in the City is represented as a white dot on the map. The density of lighting generated
is represented from gray and blue in the lowest light density areas to yellow in the highest light density
areas. Not surprisingly, the highest density lighting occurs in Salt Lake’s commercial areas including
downtown and the Sugar House business district and along arterials and other major highways.
Lowest light density occurs in residential neighborhoods, parks, and industrial areas. Non-Salt Lake
City Public Utilities lighting, including the interstate highways, at the University of Utah and at the Salt
Lake International Airport, is not represented.
Figure 3: Street Light Density Map
25
CURRENT SYSTEM EVALUATIONEVALUATION BY COMMUNITY / DISTRICT
The approach to recommended street lighting improvements in this plan is influenced and informed
by the street classification, adjacent land use, pedestrian levels, and specific situations found in each
area of the City.
Because past policies focused on street lighting for safety on the City’s roads, most areas of the
city have lighting in compliance with IES and APWA road safety standards. As seen in the summary
adopted master plan goals and implementation measures, many neighborhoods in the city would like
to see additional pedestrian level lighting. Figure 4 is a map of the existing character districts in the
City.
Sugar House
Wasatch
Hollow
Liberty Wells
Glendale
Central
City/Liberty
Wells
Yalecrest
Ballpark
Central City
DowntownPoplar Grove
Fairpark
Rose Park Capitol Hill
Westpointe
Greater
Avenues
SL International
Airport
East
Liberty
Wells
East
Central/Yalecrest
East Central
East
Central/East
Liberty Park
Downtown/
Central 9th
Ballpark/Central
9th
East
Central/University
Gardens
Federal
Heights/Greater
Avenues
Residents, developers, and other interested parties can identify existing lighting location and type
using the interactive map on the city’s website. The map provides the following information:
• Location
• Pole type
• Luminaire type
• Light source
Figure 4: Community Character Map
26
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
THIS PAGE LEFT INTENTIONALLY BLANK
27
PLAN GUIDEPOSTS PLAN GUIDEPOSTThe Advisory and Technical Committees
developed a series of guideposts as a basis
of evaluating street and pedestrian lighting
characteristics.
The four guideposts:
• Safety
• Character
• Responsibility
• Equity
Lighting improvement strategies and
characteristics were evaluated based on
these guideposts. The safety, character and
responsibility guideposts depend on the district
in which the lighting is located and adjacent
land uses. The equity guidepost underpins
the entire plan and implementation strategy
to encourage lighting improvements based on
community need. The guideposts are intended
to result in design decisions that contribute to
safe and comfortable nighttime environments.
The application of the guideposts and the
design decisions they affect contribute to
identifying lighting designs and approaches
that best fit the needs of each project.
SAFETY
Appropriate street and pedestrian lighting
improves safety by improving visibility for
drivers, bikers, and pedestrians. Effective
visibility in the nighttime environment depends
more on the quality of light than the quantity.
Higher light levels do not always result in better
visibility. The qualities of light that achieve
excellent visibility and therefore improve safety
are:
• Appropriate Light Level
• Reduced Glare
• Uniformity vs. Contrast
• Adaptation
• Color
CHARACTER
Salt Lake City’s existing street and pedestrian
lighting is diverse with a variety of historic
and industrial cobra-head style lights. Special
Districts use street lighting to create distinct
character and enhance the unique identity
of the district. The characteristics of street
and pedestrian lighting that can support and
enhance the character of an area include:
• Scale: Street Scale, Pedestrian Scale
• Style: Luminaires, Mounting Brackets, Poles,
Pole Bases, Additional Amenities
• Appropriate Light Level
• Glare
• Color: Finish Color, and Color of Light Source
RESPONSIBILITY
Responsible implementation of street lighting
includes minimizing potential negative effects
of light intensity and spectrum on human and
ecological health balanced with the responsible
use of public funds. This is a complex challenge
that includes many issues that sometimes
require balancing opposing opinions and
perspectives. This Master Plan references the
28
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1EXISTING CONDITIONSlatest research in the effects of light intensity
and spectrum on visibility and human and
ecological health in exterior nighttime
environments. To implement the Responsibility
guidepost the following issues are considered
and balanced:
• Light Trespass
• Light Pollution
• Health & Wellbeing
• Impacts on Wildlife
• Energy Use
• Cost
• Maintenance
EQUITY
The implementation of this Street Lighting
Master Plan is intended to address issues
related to street lighting in the most equitable
way possible. The prioritization of street
lighting funding will be an ongoing process
within annual budget allocations. Recognizing
that there are differing opinions throughout the
City about the balance between the Guideposts
and how to implement the Lighting Strategies
in this master plan, particularly in residential
neighborhoods, it is important that there is
ongoing public engagement to determine the
appropriate lighting strategies within each
neighborhood. While some lighting strategies
will be optional, there are some minimum
requirements for lighting improvements to
address safety needs in a consistent way
throughout the Salt Lake City.
• Ongoing Public Engagement
• Prioritizing Areas Currently Underserved by
Street Lighting
29
STREET LIGHTING BASICS OVERVIEWSTREET LIGHTING BASICS OVERVIEW
SYSTEMWIDE CONSIDERATIONS
HEALTH AND WELLBEING
The natural daily cycle of light and dark is
directly linked to the healthy sleep/wake cycles,
also known as circadian rhythm. Light is the
primary stimulus that triggers the suppression
of melatonin in humans. Darkness at night is
needed to allow the production of melatonin
for healthy and complete sleep. Exposure to
blue spectrum light after sunset can delay the
nighttime production of melatonin. Controlling
glare and light trespass and using light sources
with warmer color reduces the exposure to blue
spectrum content of LED for street, pedestrian,
and area lighting. Warmer colors encourage
healthy melatonin and sleep patterns for
residents. It is also important to note that
the current status of research related to light
exposure at night and human health is still
ongoing. According to the Lighting Research
Center1 at typical street lighting levels, per IES
RP-8-18, using LED light sources are “below the
threshold for suppressing nocturnal melatonin
(in humans) by light at night following a
30-minute exposure”.
WILDLIFE IMPACTS
Salt Lake City contains important wildlife
habitat, from the foothills in the east to the
open shore lands of the Great Salt Lake.
Additional wildlife habitat is found along the
north-south route of the Jordan River and
along the four urban creeks extending west
and south out of the foothills. Light at night
can disrupt these wildlife habitats. Migratory
species pass through the city itself, with
nocturnally migratory birds attracted to the
city lights. Controlling light pollution and light
trespass, using only necessary lighting levels,
and choosing an appropriate spectrum (color)
of light for each area can protect these natural
resources. Dimming lights during seasonal bird
migrations is another wildlife-friendly approach.
LIGHTING CHARACTERISTICS
Each of the following characteristics represent
considerations and decisions to be made in
implementing street lighting in the various
areas and neighborhoods of the city. Each
characteristic is evaluated based on each of
the guideposts. When one or more of the
guideposts converge and coalesce around the
characteristic, synergy is created. When the
guideposts diverge decisions must be made to
balance competing needs.
Each characteristic is identified and described
then evaluated based on four Guideposts. A
comparative example of the characteristic is
also included to enhance understanding of the
concept.
APPROPRIATE LIGHT LEVELS
Appropriate light levels vary based on roadway
classification, adjacent land use, pedestrian
activity, and proximity to open space and wildlife
habitat. The recommendations in the plan apply
adaptive lighting criteria to the Illuminating
Engineering Society’s Recommended Practice
for Street and Roadway Lighting (IES RP-8-18)
to allow for dimming during reduced pedestrian
activity and the use of broad spectrum, white
light sources, such as LED.
Character, Safety and Equity converge around moderate
light levels.
• Using appropriate amounts of light increases
nighttime visibility creating a safer and more
comfortable environment.
Figure 5: Appropriate Light Level
1 Rea MS, Smith A, Bierman A, Figueiro MG. 2012. The potential of outdoor lighting for stimulating the
human circadian system. Alliance for Solid-State Illumination Systems and Technologies (ASSIST)
30
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1STREET LIGHTING BASICS OVERVIEW • The City is working to upgrade lighting to appropriate light levels based on locations with the
greatest need.
Appropriate light levels are balanced with environmental responsibility.
• In environmentally sensitive areas, lower light levels are desired. The City will be installing more
environmentally friendly luminaires with a lower CCT and better glare control
Appropriate Light Levels: This photo demonstrates appropriate light levels for a commercial area with medi-
um to high pedestrian usage, where moderate light levels provide excellent visibility through out the public
streets and sidewalks.
31
STREET LIGHTING BASICS OVERVIEWGLARE REDUCTION
Glare is caused by excessive or undesirable
light entering the eye from a bright light source.
Glare can result in discomfort, annoyance, and
decreased visibility. There is the potential for
direct glare when a light source is in direct view.
The presence of direct glare depends on the
intensity of the light source and contrast with
the surrounding environment. With direct glare,
the eye has a harder time seeing contrast and
details. A lighting system designed solely on
lighting levels aim more light at higher viewing
angles, thus producing more potential for glare.
Direct glare can be minimized with careful
equipment selection as well as placement.
Character, Safety, Equity, and Responsibility converge
around reducing glare levels as it leads to more effective
lighting and safer, more comfortable environments.
Reducing glare:
• Improves visibility on the roadways
• Creates a more enjoyable nighttime
environment
• Reduces sky glow and light trespass,
minimizing the obtrusive effects of light.
Figure 6: Glare Reduction
Lights that create glare can result in a range
of negative effects for drivers, pedestrians
and residents. From annoyance to reduced
visibility, and may generate complaints from
residents.
Lights with low glare provide more comfortable
streets and public spaces, providing lights,
where it is needed without annoying nearby
residents.
32
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1STREET LIGHTING BASICS OVERVIEWUNIFORMITY VS. CONTRAST
Lighting uniformity refers to the evenness
of light. Our eyes are continually adapting to
the brightest object in our field of view. Any
object lighted to 1/10 the level of the immediate
surroundings appears noticeably darker. For
roadway lighting, good uniformity indicates
evenly lighted pavement. However, good
visibility requires the contrast of an object
against the background. An environment
with perfectly uniform lighting provides
low contrast, which can reduce visibility. To
create enough contrast for good visibility,
there should be a balance between uniform
perception and having enough contrast to
improve visual detection of objects on the road.
Uniformity criteria are typically described as
ratios of maximum to minimum and average to
minimum luminance or Illuminance. Contrast is
the difference between two adjacent luminance
values. High contrast is necessary for good
visibility. Differences in color also produce a
visible contrast, even when both objects have
similar luminance values, which support the
benefits of using higher color rendering sources,
as discussed below in the Color Rendering and
Nighttime Visibility section.
Character, Safety, Equity, and Responsibility converge
around semi-uniform medium contrast lighting. This
provides the proper balance of uniformity and contrast
and is essential to quality lighting design.
• Safety on the roadway is improved when
street lighting properly strikes this balance,
and subtle contrast can add character to an
area with a unique lighting design.
• When the proper balance of uniformity and
contrast is achieved, the lighting is more
effective at lower light levels reducing over
lighting and light pollution.
Figure 7: Uniformity Vs. Glare
Color Contrast: In the photos above, the black-
and-white image shows that the luminance of
the flower and background are very similar. Only
when the color is rendered does the color con-
trast of the yellow flower make it highly visible
next to its background. This demonstrates why
street lighting with good color rendering can im-
prove visibility of objects in a street, even at the
same, or lower light levels. Further study on the
effects of color contrast in street lighting appli-
cations is needed to understand the improved
visibility of broad spectrum light sources at light
levels below current IES RP-8-18 recommenda-
tions.2
2 Clanton N, Gibbons R, Garcia J, Mutmansky M. 2014. Seattle LED Adaptive Lighting Study. Northwest
Energy Efficiency Alliance Report #E14-286
33
STREET LIGHTING BASICS OVERVIEWADAPTATION
Adaptation refers to the eye’s ability to adjust
between changes in luminance. Our eye will
automatically adjust to the brightest object in
our field of view. Glare from headlights or fixed
lighting can affect one’s ability to adapt to lower
surface luminance. This is especially true as one
ages. Another form of adaptation occurs when
driving from a brightly lighted area to a non-
lighted section of roadway. Here, the lighted
area should slowly transition to darker to allow
adaptation time. Off roadway brightness, such
as driving past a brightly lighted gas station
or LED sign, can also cause adaptation issues.
While this Master Plan does not directly address
lighting on private property, it is intended to
set an example for future lighting guidelines
that could apply these lighting strategies to all
exterior lighting in Salt Lake City.
Character, Safety, Equity, and Responsibility converge
around low to medium levels of visual adaptation to
improve visibility when transitioning from private parking
lots and property into public streets.
• When street lighting and adjacent private
lighting is designed to appropriate light
levels, the eye can maintain a proper degree
of adaptation. When the eye is adapted
to the existing light, it is more effective at
detecting and identifying objects, increasing
safety.
Figure 8: Adaptation
The privately owned lighting at this auto dealership
are too bright and lack proper shielding creating
high adaptation issues transitioning from the sales
lot to the street.
When roadways are illuminated to appropriate
light levels with good control of light, the eye is
able to adapt, increasing visibility and safety on the
streets.
34
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1STREET LIGHTING BASICS OVERVIEWCOLOR RENDERING AND NIGHTTIME VISIBILITY
The Color Rendering Index (CRI) is the
standard metric used to evaluate how well a
light source renders the true color of an object.
CRI is measured on a scale of 0 to 100, with
100 representing how an object would look
under a reference incandescent light source.
The higher the number, the better the color
rendering capacity. Traditional High-Pressure
Sodium (“HPS”) streetlights have a very low CRI
of approximately 30, making color detection
difficult. Today’s standard LED streetlights are
not only significantly more energy efficient,
they also have a much higher CRI, typically 65 or
higher, increasing color detection, visual acuity,
and overall effectiveness of the streetlights.
LED lighting technology advancements
allow streetlights to be tuned to a specific
correlated color temperature (“CCT”) without
drastically reducing the CRI. This technology
can be used to reduce the color temperature
in environmentally sensitive areas without
significantly reducing the CRI, preserving the
effectiveness of the lighting system.
LED’s emit light across the visual spectrum,
considered white light, which appears brighter
at night. When traditional HPS lights are
replaced with LED’s similar light levels often
appear to be much brighter with LED lights.
Residents may find the light to be obtrusive.
When upgrading to LEDs in residential areas,
it is essential to have a dimming system to
respond to complaints from residents.
Safety and character converge around using higher CRI
of 65 or higher. Eliminating blue spectrum light with
lower CRI is responsible in areas with critical wildlife
habitat.
• Using a higher CRI improves safety by
increasing visual acuity and object detection,
making the roads safer or vehicles and
pedestrians.
• Higher CRI improves character in the area by
enhancing colors of landscaping and objects
within the streetscape.
• Within or adjacent to critical wildlife areas a
luminaire with a lower CRI and CCT should
be used to responsibly illuminate the area
while also minimizing impacts on wildlife.
This car is illuminated by two different light sources.
On the left, an LED light, with high color rendering,
clearly reveals the color and details of the car. On
the right, a low pressure sodium light, with low color
rendering, distorts the color of the car and details of
the vehicle are not clear.
Figure 9: Color Rendering
35
STREET LIGHTING BASICS OVERVIEWCOLOR TEMPERATURE AND NIGHTTIME
VISIBILITY
Appropriate Correlated Color Temperature
(CCT) of streetlights is largely depends on the
location of the lights within the city. Salt Lake
City consists of diverse land uses, ranging from
high density urban areas to environmentally
sensitive lowlands and foothills. Street type and
adjacent land use determine the appropriate
color of light.
There are opposing effects on how the
spectrum of light at night affects visibility for
Safety and human and environmental health for
Responsibility. Limiting the CCT of light sources
for the City to a maximum of 3000K, and then
adjusting to warmer CCT in residential and
wildlife habitats provides a balance between
the guideposts. CCT should vary throughout
the City to achieve comfortable, safe and
responsible street and pedestrian lighting
throughout the City.
• High Density Urban Areas – 3000K CCT (max).
Lighting in higher density urban areas should
prioritize color rendering for color contrast
and object detection on the roadway. This
increases visibility for drivers and pedestrians.
In urban areas light should have a CCT of
3000K. This CCT is considered a warm white
light source, which improves visibility at night,
but also minimizes the amount of light in the
spectrum that can cause disruptions to the
surrounding environment as well as human
health. The American Medical Association
and International Dark Sky Association both
recommend a maximum CCT of 3000K.
• Residential Areas – 2700K CCT (max).
Visual acuity from white light sources is
needed for pedestrian safety, but residents
typically prefer a warmer color temperature
in their neighborhood. The recommended
color temperature for residential local and
collector streets is 2700K. On arterial streets
in residential areas, 3000K CCT should be
used due to increased speeds. This range
will provide the appropriate amount of white
light to preserve object detection but will also
allow a warmer, more comfortable color of
light in neighborhoods.
• Environmentally Sensitive Areas – 2200K
CCT (max). There are varying types of
environmentally sensitive areas within and
along the perimeter of the city. Where streets
pass through or adjacent to environmentally
sensitive areas, very warm, phosphor-
converted amber light sources with CCT of
2200K or lower, should minimize impacts
of light on plants and animals in the area.
Additional shielding of both back light and
front light may also be required to further
reduce light trespass into these sensitive
areas.
Figure 10: Color Temperature
In the distance, the warm amber glow of low CCT
(1800K) high pressure sodium street lights is shown
in comparison to higher CCT (4000K) LED street
lights in the foreground.
36
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1STREET LIGHTING BASICS OVERVIEWLIGHT TRESPASS
Light trespass is defined as a stray light that
crosses a property boundary. The most obtrusive
form of light trespass is often caused by an
excessively bright luminaire that is unshielded
and distributes light into adjacent property.
Uncontrolled, non-shielded light sources are
usually the cause of light trespass. However,
even a controlled, fully shielded luminaire may
cause light trespass if not properly located
or oriented. In cases where the location of a
light standard cannot be changed, additional
shielding may be necessary to prevent light
trespass. Although designers should always
strive to minimize light trespass, sometimes
higher levels may be acceptable in downtown,
commercial, and area adjacent to civic land
uses.
The following strategies will identify acceptable levels
of light trespass to balance the design guideposts.
• When designing in residential areas and
environmentally sensitive areas, minimizing
light trespass should be the highest priority.
• When designing in downtown commercial
or retail environments, pedestrian safety
should prioritize increasing vertical light
levels in crosswalks.
• The character of a certain light may result in
high levels of light trespass, but designers
should strive to find luminaires that meet the
character of the area while still maintaining
zero uplight and minimizing light at angles
known to be obtrusive.
A pedestrian light with inappropriate light
distribution and poor shielding creates a
significant amount of light trespass on a nearby
residence.
Figure 11: Light Trespass
A well shielded street light with appropriate
light distribution provides adequate light for
the street and sidewalk with minimal light spill
beyond the sidewalk.
37
STREET LIGHTING BASICS OVERVIEWLIGHT POLLUTION
Light pollution and sky glow are caused by
light aimed directly up into the sky and by
light reflected from the ground or objects.
Any additional light will add to light pollution.
However, it is the direct uplight component
that does not contribute to useful street level
visibility, and is the most objectionable form
of pollution. Unshielded luminaires are major
contributors to sky glow. Over lighting, even
with fully shielded or U0 luminaires, reflects
unnecessary light into the atmosphere and
adds to sky glow. To minimize light pollution,
first minimize the overall amount of light.
Exterior lighting should be used only where
and when it is needed. Define the lighting
requirements of each street or public area and
provide only the necessary lighting. Street and
pedestrian lighting in residential areas should
be dimmable and have house side shielding
options to allow the City to proactively address
specific complaints about light pollution or
light trespass.
All lighting in the city should be designed
based on the criteria in this plan to reduce over
lighting. In addition, lighting should be shielded
and dimmable.
The strategies to limit light pollution are similar to those
identified for Light Trespass.
• Lighting in environmentally sensitive areas
should always prioritize minimizing light
pollution by not over lighting and using
luminaires with zero uplight and minimal
light at high angles.
• In areas of heavy pedestrian traffic, light at
higher angles may be necessary to provide
the vertical illuminance and positive contrast
to safely light crosswalks with more light at
higher angles.
• Decorative luminaires can contribute more
to sky glow, but designers can still install
decorative luminaires with minimal uplight
component that maintain the historic
character of the area.
The historic acorn style lights currently used
on the Downtown “Cactus” pole distribute a
significant amount of light upward, contributing
to increased light pollution and sky glow.
Figure 12: Light Pollution
38
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1STREET LIGHTING BASICS OVERVIEWCOSTS AND IMPLEMENTATION
The implementation of this Street Lighting
Master Plan will require additional investment
in the lighting and electrical infrastructure
throughout Salt Lake City and multiple years
to install. To ensure the equitable distribution
of street lighting improvement projects,
this Master Plan recommends how the City
prioritizes these projects and some changes
in the funding mechanisms. The current
funding strategy provides a base level of street
lighting under the standard Public Utility Street
Lighting Fee. To apply for additional pedestrian
scale lighting under the Special Improvement
Districts program, an additional fee is required
to install pedestrian scale lighting in a specific
neighborhood. This results in more affluent
neighborhoods with more lighting than less
affluent neighborhoods. The City should
develop an alternative funding mechanism
that provides more equitable distribution and
access to pedestrian scale lights throughout
the City, not just in areas that can afford the
additional fees.
INITIAL COSTS
The initial investment in street and pedestrian
lighting improvements will vary based on the
strategy chosen to bring the current system
into compliance with this plan. Comprehensive
improvements, such as lighting redesign,
will have the highest initial costs, whereas
1-for-1 replacements of existing luminaires
will have lower initial costs. In many areas
the 1-for-1 replacement strategy will achieve
plan purposes. Other areas require more
comprehensive improvements, such as
relocation of poles or installation of new
lighting. Costs included design and engineering
costs (Design & Construction Documents,
Utility Surveying), lighting equipment costs
(Luminaires, Poles, Lighting Controls), and
infrastructure costs (Foundations, Conduit &
Wire, Surface Replacement).
The public engagement process identified that increasing
the use of pedestrian scale lighting is a community-wide
high priority. Prioritization of pedestrian scale lighting
upgrades include:
• Lighting upgrades and additional pedestrian
lighting in currently underlit areas.
• Strategic placement and appropriate light
levels will minimize power consumption and
eliminate unnecessary equipment.
• Lighting upgrades and new projects in areas
identified as critical wildlife habitats using
proper equipment and lighting levels.
LONG TERM LIFE CYCLE COSTS
• Changing to LED lighting will drastically
reduce the life cycle and operating costs
of the street lighting system. LED lighting
requires significantly less power than legacy
sources, such as high-pressure sodium,
reducing the life cycle energy costs of the
system. With a lifespan of up to 100,000
hours, LEDs need to be replaced significantly
less often than legacy luminaires, reducing
maintenance costs.
• Energy Costs (Luminaire Watts, Dimming,
Part-Night Lighting, Annual kWh baseline,
Annual kWh projected)
• Maintenance Costs (Minimizing Lighting
Equipment SKUs, Equipment Life)
Figure 13: Initial Costs: Guidepost Synergy &
Balance
39
STREET LIGHTING BASICS OVERVIEWMAINTENANCE
• Proper maintenance is critical for the
effectiveness of the lighting design. LEDs
are known for their durability, longevity,
and consistency in lighting, but quality
components are essential to ensure this.
The LED electronic driver will fail first if a
low-quality luminaire is purchased. Planning
and budgeting for high-quality luminaires
ensures a longer lifespan with much less
required maintenance.
• Another aspect of maintenance involves the
dirt and dust that can accumulate inside or
on the outside lenses of luminaires. Because
street lighting will rarely, if ever, be cleaned,
luminaires must have adequate ingress
protection (IP) against dust and water.
Requiring the use of street and pedestrian
luminaires with a minimum rating of IP65
means that the luminaire is dust-tight and
watertight.
ENERGY
Reducing energy use in Salt Lake City can be
achieved by using energy efficient LED light
sources, providing appropriate light levels
without over-lighting, and reducing light levels
after a curfew by dimming or turning off non-
essential lighting.
Reduction in Energy use for street and pedestrian lighting
is consistent with the guideposts as transitioning all
lighting to LED significantly reducing the amount of
energy that will be used.
• The City is striving to reduce over lighting
by installing a control system to allow for
dimming and further reduction of lighting,
adding to the energy savings.
• In more environmentally sensitive areas, this
master plan requires phosphor converted
amber LEDs with additional shielding.
Although these do not use as much energy
as legacy light sources, they are still not as
efficient as broad spectrum white LEDs.
These lights will be used to reduce the
adverse effects of lighting on the wildlife in
ecologically sensitive areas.
STANDARDIZATION
Salt Lake City has a very diverse street and
pedestrian lighting system that utilizes historic
decorative lights of various types and provides
distinct character to different districts within
the City. Providing variety of character requires
Public Utilities to stock more components to
service and maintain the lighting system. While
this Street Lighting Master Plan establishes
Character as one of its Guideposts, this must
also consider the balance with Responsibility
to minimize costs and inventory for Public
Utilities to manage and maintain the street and
pedestrian lighting system within their budget.
To strike this balance between Character and
Responsibility, this Street Lighting Master Plan
intends to provide some variety of options
within a set of Standardized Components.
• Luminaire Styles
• Pole Styles
• Armature Styles
• Base Styles
• Color Options
Figure 14: Energy
40
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
STREET LIGHTING PLAN
LIGHTING IMPROVEMENT STRATEGIES
PURPOSE
There are several strategies the city can use
to implement this Street Lighting Master
Plan and improve the quality of street and
pedestrian lighting. Each of the strategies
will result in a safe environment for drivers
and pedestrians while using equipment that
minimizes light pollution and light trespass.
The plan recommends that the city utilize
each of the strategies as appropriate for the
specific current streetlighting configuration,
road classification, pedestrian volume adjacent
land use, neighborhood or districts character
and the presence of environmentally sensitive
wildlife areas. In addition, each strategy
should be discussed through a neighborhood
engagement process and reviewed to ensure
an optimal balance of the four guideposts is
achieved.
LIGHTING LAYOUT STRATEGIES
Volume II – Technical Lighting Development
Guide of this Master Plan provides a matrix
by which the appropriate strategy should be
identified using street types and warrants. The
matrix is applied on a block by block basis to
ensure the most appropriate lighting for each
area. Figure 15 is a snapshot of the Salt Lake
City Lighting Warrants matrix described in
more detail in Volume II.STREET LIGHTING BASICS OVERVIEW
41
STREET LIGHTING BASICS OVERVIEWPEDExisting ConditionsStreet Lighting Ped LightingPEDExisting ConditionsStreet Lighting Ped LightingPEDExisting ConditionsStreet Lighting Ped LightingSidewalk Lit By StreetlightContinuousOptional Non-cont.Sidewalk Lit By StreetlightContinuousORContinuousSidewalk Lit By StreetlightContinuousORContinuousSidewalk NOT Lit by StreetlightContinuous&ContinuousSidewalk NOT Lit by StreetlightContinuous&ContinuousSidewalk NOT Lit by StreetlightNon-cont.&ContinuousSidewalk Lit By StreetlightContinuousOptional Non-cont.Sidewalk Lit By StreetlightContinuousORContinuousSidewalk Lit By StreetlightNon-Cont. ORContinuousSidewalk NOT Lit by StreetlightContinuous&Non-cont.Sidewalk NOT Lit by StreetlightContinuous&Non-cont.Sidewalk NOT Lit by StreetlightNon-cont.ORContinuousSidewalk Lit By StreetlightNon-Cont.NASidewalk Lit By StreetlightNon-Cont.NASidewalk Lit By StreetlightInt. OnlyORNon-cont.Sidewalk NOT Lit by StreetlightNon-cont.NASidewalk NOT Lit by StreetlightNon-cont.NASidewalk NOT Lit by StreetlightInt. OnlyORNon-cont.Sidewalk Lit By StreetlightNon-Cont.NASidewalk Lit By StreetlightNon-Cont.NASidewalk Lit By StreetlightInt. OnlyORNon-cont.Sidewalk NOT Lit by StreetlightNon-cont.NASidewalk NOT Lit by StreetlightNon-cont.NASidewalk NOT Lit by StreetlightInt. OnlyORNon-cont.Cactus PolesCactus PolesCactus PolesSidewalk Lit By StreetlightContinuousOptional Non-cont.Sidewalk Lit By StreetlightContinuousORContinuousSidewalk Lit By StreetlightContinuousORContinuousSidewalk NOT Lit by StreetlightContinuous&ContinuousSidewalk NOT Lit by StreetlightContinuous&ContinuousSidewalk NOT Lit by StreetlightNon-cont.&ContinuousCactus PolesCactus PolesCactus PolesSidewalk Lit By StreetlightContinuousOptional Non-cont.Sidewalk Lit By StreetlightContinuousORContinuousSidewalk Lit By StreetlightNon-Cont. ORContinuousSidewalk NOT Lit by StreetlightContinuous&Non-cont.Sidewalk NOT Lit by StreetlightContinuous&Non-cont.Sidewalk NOT Lit by StreetlightNon-cont.ORContinuousSidewalk Lit By StreetlightInt. OnlyNASidewalk Lit By StreetlightInt. OnlyNASidewalk Lit By StreetlightInt. OnlyNASidewalk NOT Lit by StreetlightInt. OnlyNASidewalk NOT Lit by StreetlightInt. OnlyNASidewalk NOT Lit by StreetlightInt. OnlyNASidewalk Lit By StreetlightContinuousOptional Non-cont.Sidewalk Lit By StreetlightContinuousOptional Non-cont.Sidewalk Lit By StreetlightInt. Only&ContinuousSidewalk NOT Lit by StreetlightContinuous&Non-cont.Sidewalk NOT Lit by StreetlightContinuous&Non-cont.Sidewalk NOT Lit by StreetlightInt. Only&ContinuousSidewalk Lit By StreetlightContinuousOptional Non-cont.Sidewalk Lit By StreetlightNon-Cont.ORNon-cont.Sidewalk Lit By StreetlightInt. OnlyOptionalNon-Cont.Sidewalk NOT Lit by StreetlightContinuousOptional Non-cont.Sidewalk NOT Lit by StreetlightInt. Only&Non-cont.Sidewalk NOT Lit by StreetlightInt. OnlyOptionalNon-cont.Sidewalk Lit By StreetlightNon-Cont.NASidewalk NOT Lit by StreetlightNon-cont.NASidewalk Lit By StreetlightInt. OnlyNASidewalk Lit By StreetlightInt. OnlyNASidewalk Lit By StreetlightInt. OnlyNASidewalk NOT Lit by StreetlightInt. OnlyNASidewalk NOT Lit by StreetlightInt. OnlyNASidewalk NOT Lit by StreetlightInt. OnlyNAOffice ParkOffice ParkOffice ParkLowLowLowLowLowCommercialHigh CommercialHigh CommercialHigh MedMedMedSLC Lighting WarrantsArterial StreetCollectorLocalLowMedMedMultifamily ResidentialLowHigh DowntownMedLowLowMedMedMedLowLowLowSingle Family ResidentialOpen SpaceNANAMultifamily ResidentialSingle Family ResidentialOpen SpaceMultifamily ResidentialSingle Family ResidentialOpen SpaceMedLowIndustrialIndustrialIndustrialHigh High MedMedContinuous Cactus Pole LightingContinuous Cactus Pole LightingLowLowDowntownContinuous Cactus Pole LightingContinuous Cactus Pole LightingContinuous Cactus Pole LightingContinuous Cactus Pole LightingDowntownFigure 15 - Street Lighting Warrants Matrix
42
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1STREET LIGHTING BASICS OVERVIEWThis section summarizes the strategies identified in the matrix.
STREET LIGHTING ONLY
PURPOSE
• Quality street lighting must consider the entire context of the streetscape environment,
extending beyond the street itself to provide quality light for sidewalks while controlling
obtrusive light trespass, glare and light pollution.
• Street trees with large canopies and thick foliage are integral to the character of Salt Lake
City’s streets and public realm. Street Lighting Only can be a successful strategy in areas that
have smaller and fewer trees but may result shadowing sidewalks on streets with large trees.
• The wide streets and right-of-way in Salt Lake City provide opportunities on many streets to
have a very wide Park Strip that separates the sidewalk from the street. The width of the Park
Strip also affects the ability of Street Lighting Only to effectively illuminate the sidewalks.
Figure 16: Street Lighting Only Cross Section
43
STREET LIGHTING BASICS OVERVIEWSTREET AND PEDESTRIAN LIGHTING
• A combination of Street and Pedestrian Lighting is used in areas of high pedestrian activity,
and on streets with street trees that create shadowing, or with wide Park Strips where Street
Light Only is ineffective at illuminating the sidewalks. This will support a safer and more visually
comfortable pedestrian environment.
Figure 17: Street & Pedestrian Lighting Cross Section
44
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1STREET LIGHTING BASICS OVERVIEWPEDESTRIAN LIGHTING ONLY
• Pedestrian lighting helps differentiate an area as pedestrian centric and is a visual cue for
drivers to be more aware of people in the public right of way.
• Pedestrian lighting in residential areas reduces light trespass into homes, and the character of
the lights can differentiate neighborhoods throughout the city.
• In downtown environments, pedestrian lighting identifies restaurants, retail and other pedestrian
centric areas, creating a more inviting and safer place for people walking the city.
• When using this Pedestrian Lighting Only strategy, street lights should still be located at
intersections.
Figure 18: Pedestrian Only Lighting Cross Section
45
STREET LIGHTING BASICS OVERVIEWSPECIAL LIGHTING DISTRICTS
• There is a rich history of street lighting in Salt Lake City that has established Special Lighting
Districts with unique street lighting character. Areas like Downtown and Sugarhouse District
have unique historic street lighting that with a combination of both street and pedestrian lights
mounted on the same light pole. As Salt Lake City evolves, new Special Lighting Districts
may be desired to create and enhance a unique sense of place. Any new Special Lighting
Districts must be coordinated with Salt Lake City to determine the ownership and maintenance
agreements, and must follow the lighting strategies and lighting criteria established in this
Street Lighting Master Plan.
Figure 19: Cactus Lights Cross Section
46
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1STREET LIGHTING BASICS OVERVIEWINTERSECTION LIGHTING
• Proper lighting at intersections is critical for vehicle and pedestrian safety throughout the
entire city.
• Intersection lighting is the minimum standard throughout the city.
• Intersection lighting encompasses the roadway after the stop bar as well as any painted
crosswalks.
• See Intersection & Crosswalk Lighting for layout and spacing criteria.
Figure 20: Intersection Lighting Plan
47
STREET LIGHTING BASICS OVERVIEWVERTICAL ILLUMINATION IN CROSSWALKS
• Proper crosswalk lighting in high traffic areas, commercial corridors, will support a safer and
more pedestrian friendly city.
• Lighting in the vertical plane will increase visibility in crosswalks and help to reduce vehicle-
pedestrian accidents.
• See Intersection & Crosswalk Lighting for layout and spacing criteria.
Figure 21: Crosswalk Lighting
48
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
BUS STOP
• Uncovered bus stops should be lit by a
street luminaire positioned 1/2 to 1 mounting
height from the bus stop in the direction of
oncoming traffic.
• Bus shelters with integrated lights should
provide vertical illumination to aid in facial
recognition. Street lights in close proximity
increase ambient light and visual comfort.
• See Volume 2 for additional information.
ENVIRONMENTALLY PROTECTED AREAS
The Salt Lake Valley is not only home to a
bustling urban city but is also home to diverse
and vulnerable wildlife populations and sensitive
Dark Sky Areas. Salt Lake City recognizes
the impacts that street lighting can have on
these sensitive areas and wants to minimize
the negative effects of street lighting at night.
The map below highlights environmentally
sensitive areas where the following lighting
characteristics should be used:
• Color Temperature (CCT) no higher than
2200K,
• All lights should have increase backlight
control to reduce the amount of spill light
• All lights should have zero uplight.
To read more on the impacts of light at night
within the Salt Lake Valley, reference Appendix
D: Nocturnal Infrastructure for Ecological
Health.
IMPLEMENTATION OF UPGRADED LIGHTING
When deciding which Lighting Layout Strategy
to use at various locations throughout the
city, the adjacent land use is a critical factor
in determining nighttime pedestrian activity.
Although there are many different zoning
designations in Salt Lake City, this master
plan consolidates land uses into seven
different categories: Commercial, Office Park,
Downtown, Industrial, Multi-Family Residential,
Single Family Residential, and Open Space. The
different adjacent land uses throughout the city
and more information on determining adjacent
land use can be found in Volume 2.
Each adjacent land use has different primary
considerations that determine lighting
strategy and criteria. The most critical of these
considerations is pedestrian and vehicle volume
during nighttime hours. Areas of higher volume
at night, such as Downtown and Commercial,
require additional lighting, whereas industrial
areas do not see the same traffic volumes
during dark hours. This Master Plan also
strives to be environmentally responsible, and
balances vehicle and pedestrian safety with
environmentally protective actions based
on adjacent land use. The table below shows
the main considerations, environmentally
protective actions, max CCT, and lighting
strategies for each adjacent land use. STREET LIGHTING BASICS OVERVIEW
49
STREET LIGHTING BASICS OVERVIEWTABLE 5: LIGHTING LAYOUT STRATEGY BY LAND USE
ADJACENT LAND USE MAIN CONSIDERATIONS
ENVIRONMENTALLY
PROTECTIVE ACTIONS MAX CCT*LIGHTING STRATEGIES
Commercial • Diverse Land Use with
High, Medium, and
Low Pedestrian and
Vehicle Activity During
Night Hours
• Adaptive
Dimming
• 3000K • All Lighting
Strategies
Possible to Safely
and Appropriately
Light the Streets
and Sidewalks.
Office Park • Low Pedestrian
Conflict at Night
• Overlap with
Environmentally
Protected Areas
• Lower CCT
• Adaptive
Dimming
• 3000K • Non-Continuous
Street Lighting
• Possible Non-
Continuous
Pedestrian
Lighting
Downtown • High and Medium
Pedestrian and Vehicle
Activity During Night
Hours
• Historic Character
using Cactus Pole
Lights
• Adaptive
Dimming
• 3000K • Continuous Street
and Pedestrian
Lighting
Industrial • Low Pedestrian
Conflict at Night
• Environmental
Concerns
• Lower CCT
• Adaptive
Dimming
• 2200K • Street Lighting at
Intersections Only
Multifamily
Residential
• Pedestrian Safety
• Representing the
Character of the Area
• Minimizing Light
Trespass
• Controlling
Spectrum
• Adaptive
Dimming
• 3000K
(Arterial)
• 2700K
(Collector/
Local)
• Continuous and
Non-Continuous
Street Lighting
• Continuous and
Non-Continuous
Pedestrian
Lighting
Single Family • Pedestrian Safety
• Representing the
Character of the Area
• Minimizing Light
Trespass
• Controlling
Spectrum
• Adaptive
Dimming
• 3000K
(Arterial)
• 2700K
(Collector
Local)
• Continuous and
Non-Continuous
Street Lighting
• Continuous and
Non-Continuous
Pedestrian
Lighting
Open Space • Environmental
Concerns
• Minimizing Light
Trespass
• Controlling
Spectrum
• Adaptive
Dimming
• 2200K • Non-Continuous
Street Lighting
• Street Lighting at
Intersections Only
*Max CCT to be 2000K in Environmentally Sensitive Areas.
50
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1STREET LIGHTING BASICS OVERVIEWSTREET LIGHTING EQUIPMENT
AND TECHNOLOGY
When future improvements are made to the
lighting throughout Salt Lake City, the lighting
equipment selected should reflect the principles
established by the Guideposts of Safety,
Character and Responsibility. New equipment
should match or enhance the character of the
area, while also safely and responsible lighting
the area.
This Street Lighting Master Plan places an
increased priority on responsible lighting by
using luminaires that reduce wasted light to sky
glow and light trespass, and have the highest
levels of energy efficiency. Future luminaires
installed in the city will all be fully shielded
LED lights with no light directed upward from
the light source, understanding that there is a
minimal allowance for reflected uplight from
post-top style luminaires. As existing luminaires
are upgraded to LED and new projects are
constructed, the City will become a safer place
for pedestrians and commuters. New pedestrian
lighting will better illuminate sidewalks and
crosswalks, while all new lights will reduce glare
and improve nighttime visibility.
As these upgrades are being made to safer and
more responsible luminaires, the character of
the new lights should also match the character
of the area. The lighting equipment installed at
a particular site will depend on the character of
the site and the adjacent land use. Precedent
character, such as Downtown Cactus Poles
or Sugarhouse Teardrop luminaires, will be
upgraded to similar style of luminaire that
reduces uplight and light trespass onto adjacent
private property.
51
STREET LIGHTING BASICS OVERVIEWLuminaires (Style, Finish Color, Lumens, Distribution, CCT, CRI, BUG Rating, Shielding, Dimming
Driver (0-10V, DALI), ANSI 7-Pin Receptacle, Integral Wireless Dimming Node)
Light Standards (Pole, Arms, Base, Finish Color, Banner Arms, Holiday Receptacles, Planter Arms,
Traffic Signs, ANSI 7-Pin Receptacle (alt location))
Lighting Controls (Adaptive Dimming, Maintenance Reporting, Asset Management)
Smart City Devices (4G/5G Small Cell, Security Cameras, Air Quality Sensors, Smart Parking,
Speakers, Gun Shot Detection, EV Charging Stations, Traffic Monitoring, Noise Monitoring
TABLE 6: RECOMMENDED LUMINARIES BY LAND USE
CACTUS POLE TEAR DROP COBRA HEAD PEDESTRIAN ACORN PEDESTRIAN ARM
MOUNT
ADJACENT LAND USE
Commercial N/A
S. Temple
State Street
Sugarhouse BD
Base Level N/A Non-Continuous
or N/A
Office Park N/A N/A Base Level N/A Non-Continuous
Downtown Downtown
Historic
S. Temple
State Street
Sugarhouse BD
Base Level N/A Continuous or
Non-Continuous
Industrial N/A N/A Base Level N/A N/A
Multi-Family
Residential N/A N/A
Intersection & Mid-
Block or Intersection
Only
Rose Park Continuous or
Non-Continuous
Single Family
Residential N/A N/A
Intersection & Mid-
Block or Intersection
Only
Rose Park Continuous or
Non-Continuous
Open Space N/A N/A
Intersection & Mid-
Block or Intersection
Only
N/A N/A
52
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
LIGHTING IMPROVEMENTS COMPLEXITY & COST
Throughout Salt Lake City, there are various
existing lighting conditions, which results in
lighting improvement projects with different
levels of complexity and cost that range
from minimal improvements, such as 1-for-1
replacements, to comprehensive improvements,
such as complete lighting redesign. The
complexity and cost to improve the lighting
in certain areas will depend on the existing
lighting conditions, location within the city, and
the need for improved lighting. The City should
evaluate each site and determine which level of
improvements need to be made.
MINIMAL: 1-FOR-1 REPLACEMENTS
The most cost effective and quickest way to
improve the lighting is 1-for-1 replacements.
Salt Lake City has already begun the process
for upgrading old HPS lights to new LEDs. This
should be and has been implemented in areas
that already have acceptable existing lighting
layouts and where street lighting sufficiently
illuminates the roadway and adjacent sidewalks.
1-for-1 replacements from HPS to LED will
lead to lower life cycle costs through reduced
energy and maintenance. When upgrading
to LED luminaires, adjacent land use must be
considered. 1-for-1 replacement luminaires
should reflect the character of the area, while
also maintaining consistent light levels and
color temperature appropriate to the site.
SUPPLEMENTAL:
Additional street and pedestrian lighting
may be required where the existing lighting
layout does not sufficiently light the street or
sidewalk. Additional street lighting may be
needed if existing lights are spaced too far
apart to uniformly light the roadway, or if there
is no street lighting at all. Additional pedestrian
lights may be needed when there is a large park
strip between the sidewalk and the streetlights,
where there is excessive shadowing from
trees, or in areas where pedestrian lights are
desired. See Volume 2 on recommendations on
additional pedestrian lighting.
COMPREHENSIVE:
Comprehensive improvements to the current
conditions call for complete lighting redesign.
This should be considered in areas of the City
where lighting redesign is required to meet
requirements in the Lighting Warrants Table.
Comprehensive improvements will need to
be done on streets where new continuous or
non-continuous street or pedestrian lighting
is required. Streets without any lighting will
also require comprehensive improvements and
should comply with the lighting requirements
in the lighting warrants table.
PRIORITIZING LIGHTING IMPROVEMENTS
Evaluating where lighting improvements
should be made, and which projects should
be prioritized can be a difficult process. The
purpose of this section is to help provide
guidance when deciding where and when
lighting improvements should be made.
Areas that are currently underserved by the
existing lighting and are adjacent to “High
Priority Conflict Zones” should be the first to
be upgraded. The more “High Priority Conflict
Zones” that an underserved area is adjacent to,
the higher priority it should be to improve the
lighting. If an underserved area is not adjacent
to any “High Priority Conflict Zones” the City
should get public opinion from residents in the
neighborhood to determine is upgraded or
additional lighting is desired. STREET LIGHTING BASICS OVERVIEW
53
AREAS UNDERSERVED BY STREET LIGHTING
As seen in the lighting density map in Figure 3 on page 24, there are neighborhoods and areas
of the city currently underserved by street lighting. Public outreach is required in these areas to
identify neighborhood interest in upgrading lighting in these areas, particularly for pedestrians.
Neighborhood outreach will allow interested residents to review the options identified in the
lighting matrix and make an informed decision for their area.
HIGH PRIORITY CONFLICT AREAS
High Priority Conflict Areas are locations throughout the city where there is typically increased
pedestrian or bicycle activity. If a location underserved by the existing lighting and is near a
High Priority Conflict Area(s), that site should be prioritized. Maps showing these areas are
shown below. A site with more High Priority Conflict Areas should become a priority area for
implementation.
School Zones
Streets within a one-block radius of all schools within the Salt Lake Valley should be lighted
according to the appropriate adjacent land use and increased pedestrian conflict level as a result
of being close to a school. If a school falls within a neighborhood where minimum lighting is
desired by residents, additional lighting for pedestrian safety should be installed. Lighting near
school zones should ensure that crosswalks are sufficiently lighted as well as all entrances and
exits to the campus.
0 1 20.5
MilesSchool Overlay
Key
Lighting Strategies Heat Map
SLC Boundary
Schools
Streetlights
Dense
Sparse STREET LIGHTING BASICS OVERVIEWFigure 22: School Locations
54
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
Bus Stops
Lighting near bus stops should also be prioritized within the city. If a bus stop is not already
sufficiently lighted, placing one light on the approach side of an uncovered bus stop one half to
one mounting height is required. See Volume 2 for more information on covered and uncovered
bus stops.
1 Mile
I-215
I-15
I-80
I-80
700 E.STATE ST.FOOTHILL
SOUTH
TEMPLE
REDWOODRD.5600 W.2100 S.
400 S.
¯STREET LIGHTING BASICS OVERVIEWFigure 23: Bus Stops
55
STREET LIGHTING BASICS OVERVIEWTransit Stations
Transit stations within the Salt Lake Valley are lighted by UTA and are not within the jurisdiction on
Salt Lake City. However, these transit stations result in higher pedestrian and vehicle traffic volume
on adjacent streets. Adjacent streets should be lighted according to the appropriate adjacent land
use and the increased pedestrian volume as a result of being close to a transit station.
¯1 Mile
I-15
I-80
I-80
Transit Stops
Commuter Rail Stations
Commuter Rail
Light Rail Stations
Light Rail
I-215
I-80 700 E.STATE ST.FOOTHILL
SOUTH
TEMPLE
REDWOODRD.5600 W.2100 S.
400 S.
Figure 24: Transit Station Locations
56
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1STREET LIGHTING BASICS OVERVIEWNeighborhood Byways
Salt Lake City is working on encouraging more biking and walking in the City by creating
pedestrian centric streets called neighborhood byways. The streets should be continuous lighting
with pedestrian lights to help encourage more pedestrian travel.
¯1 Miles
I-215
I-15
I-80
I-80
700 E.STATE ST.FOOTHILL
SOUTH
TEMPLE
REDWOODRD.5600 W.2100 S.
400 S.
Figure 25: Neighborhood Byways Locations
57
STREET LIGHTING BASICS OVERVIEWPRIORITIZING 1-FOR-1 LIGHTING IMPROVEMENTS
For areas where current street lighting is adequate in terms of pole type and head placement
and type, one-for-one replacements from HPS to LEDs is the appropriate response to improve
light quality and achieve energy savings. The City is currently working toward upgrading all street
lights to LED, but should prioritize locations with existing HPS lights, are well as locations where
LED lights are glaring or obtrusive.
Streets with Existing High-Pressure Sodium
Street Lights
The City should prioritize upgrading existing HPS
lights to new LEDs with increased glare control
and dimming capabilities. More information on
selecting the proper replacement luminaire can
be found in Volume 2.
Reduce Glare and Light Trespass
Some LED lights within Salt Lake City are too
bright and can cause glare and light trespass.
These lights should be replaced with new
LEDs that have better glare control and are
compatible with the City’s lighting control
system. Additionally, some LEDs within the city
have a higher color temperature than 3000K
and should be replaced by a luminaire with
appropriate CCT based on adjacent land use.
Reduce Light Pollution from Existing Decorative
Lights
Converting the existing Cactus Pole lights
to LED lights with “U0” uplight rating will
significantly reduce the amount of sky glow
and light pollution around Salt Lake City.
EXISTING CACTUS POLE LIGHTS UPGRADED CACTUS POLE LIGHTS
58
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
DESCRIPTION OF VOLUME 2: TECHNICAL LIGHTING DEVELOPMENT GUIDESTREET LIGHTING BASICS OVERVIEW
59
LLiigghhtt TTeerrmmss aanndd DDeeffiinniittiioonn
The following terms are used throughout this Master Plan and in the lighting industry. Understanding
these terms is essential to properly understanding and implementing this Lighting Master Plan.
LLiigghhttiinngg TTeerrmm UUnniitt DDeeffiinniittiioonn
Backlight, Uplight,
and Glare (BUG)
Ratings
B0 – B5
U0 – U5
G0 – G5
Luminaire Classification System for Outdoor Luminaires per IES TM-15
describing the amount of uplight, backlight and glare. Lower numbers in
each classification are associated with lower impacts.
• BB == bbaacckklliigghhtt, or the light directed behind the luminaire.
• UU == uupplliigghhtt, or the light directed above the horizontal plane of
the luminaire.
• GG == ggllaarree, or the amount of light emitted from the luminaire at
angles known to cause glare.
Color Rendering
Index (CRI)
0 - 100 The color rendering index (CRI) is a developed metric on a scale of 0 to
100, to communicate the ability of the light to render an object’s natural
color
Continuous
Lighting
A street lighting system made up of regularly spaced luminaires along
the street. Criteria typically defines minimum and maximum illuminance
or luminance values and overall uniformity along the lighted area.
Correlated Color
Temperature (CCT)
Kelvin (K) The color appearance of the light emitted by a lamp. The CCT rating for
a lamp is a general "warmth" or "coolness" measure of its appearance.
Fire has a CCT of 1850K and daylight is 6000K.
Glare The visual sensation created by luminance (or brightness) that is
significantly higher than the surrounding luminance that the eyes are
adapted to, causing annoyance, discomfort, or loss in visual performance
and visibility (disability glare).
Illuminance Footcandle
(Fc)
The density of light (lumens per square foot) falling onto a surface.
Commonly measured in the horizontal and vertical planes.
Illuminating
Engineering
Society (IES)
The IES strives to improve the lighted environment by publishing
recommended practices to guide lighting designers, architects,
engineers, sales professionals, and researchers. The IES’s The Lighting
Handbook and Recommended Practices are the recognized authoritative
reference on the science and application of lighting.
Legacy Light
Source
All non-LED light sources: incandescent, halogen, high pressure sodium,
low pressure sodium, induction, and fluorescent.
Life Cycle Cost An economic analysis of an investment that covers all the costs and
benefits over the expected life of the equipment or system. Unlike a
simple payback analysis, it accounts for maintenance and energy even
after the system is paid for with projected savings. APPENDIX A
60
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
THIS PAGE LEFT INTENTIONALLY BLANK
61
DRAFT SURVEY
9/5/2018
-------------------------------------------------------------------------------------------------------------------------------
SURVEY QUESTIONS:
1. Place pin on map in general location of where you live or work.
o Provide map with pin location ability
2. Does the street lighting around this location allow you to feel safe while walking outside during
dark hours of the day? (Mark One)
o Yes
o No
3. If the pin located reflects where you live, does the current street lighting interfere with your
sleeping habits? (Mark One)
o Yes
o No
o N/A (Pin does not reflect location of my home)
4. What is your impression of the light level on the street you live on? (the response will change
the color of the pin)
o Comfortable (pin color: green)
o Too Dark (pin color: blue)
o Too Bright (pin color: red)
5. Do you like the color of the light source?
o Yes
o No
6. Does the light source create too much glare?
o Yes
o No
7. Please provide any additional comments:
o Write in additional comments APPENDIX B
62
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1APPENDIX B
AGENDA
PROJECT #: 2018.075 MEETING #: 2
PROJECT: SLC Street Lighting Master Plan
NEXT MEETING: Tentative: Sept 19, 2018
MEETING DATE: September 5, 2018
ISSUED BY: L. Smith | GSBS Architects
Revised post meeting
-------------------------------------------------------------------------------------------------------------------------------
ATTENDEES:
X Jesse Allen X Brad Stewart
X Lauren Smith Jesse Stewart
Christine Richmond
X Dane Sanders
X Riley Rose
X Jason Brown
X David Pearson
AGENDA ITEMS:
1. Review Public Outreach Strategy
o Advisory Committee Members
▪ District 1 Citizen Representative (identified by District Representative)
▪ District 2 Citizen Representative (identified by District Representative)
▪ District 3 Citizen Representative (identified by District Representative)
▪ District 4 Citizen Representative (identified by District Representative)
▪ District 5 Citizen Representative (identified by District Representative)
▪ District 6 Citizen Representative (identified by District Representative)
▪ District 7 Citizen Representative (identified by District Representative)
▪ Mayor’s Office Representative
▪ Public Utilities Representative
o Technical Committee Members
▪ SLC Engineering, Sean Fyfe
▪ SLC Transportation, Jon Larsen
▪ SLC Planning, Doug Dansie
▪ SLC Planning, Molly Robinson
▪ SLC Parks + Public Lands, Nancy Monteith
▪ SLC Fire
▪ SLC Police
o Stakeholder Groups (Individual Groups + representatives representing each group)
Draft List
▪ Downtown Alliance + Business Districts (9th and 9th, Sugarhouse)
▪ Environmental (Dark Sky, Tracy Aviary, Audubon)
▪ Multi-modal (UTA, Bicycle Transit)
▪ School District
▪ Inland Port, NW Quadrant
o Draft Public Survey
▪ See Attachment ‘DRAFT SURVEY’
63
2. Review Proposed Project Schedule
o See Attachment
3. Status of Contract
o Updates
4. Next Steps
o SLC Public Utilities to review pass along revised Draft Survey for review
o GSBS and Clanton to review and revise scope and fee – get to Public Utilities early next
week
o Brad to send GSBS and Clanton contact for Open City Hall to work together on upload
process and capabilities of public survey
OTHER INFORMATION:
APPENDIX B
64
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1APPENDIX B
MEETING NOTES
PROJECT #: 2018.075 MEETING #: 9
PROJECT: SLC Street Lighting Master Plan
NEXT MEETING: TBD
MEETING DATE: April 26, 2019
ISSUED BY: L. Smith | GSBS Architects
-------------------------------------------------------------------------------------------------------------------------------
These notes represent the general understanding of the author concerning the topics covered. If there
are errors or misrepresentations, please inform the author in writing and adjustments will be made with
the next issuance of notes.
-------------------------------------------------------------------------------------------------------------------------------
ATTENDEES:
X Jesse Allen, GSBS Architects Laura Briefer, Public Utilities
X Lauren Smith, GSBS Architects Holley Mullen, Public Utilities
X Dane Sanders, Clanton and Associates X Katie, Clanton and Associates
X Riley Rose, Clanton and Associates X Technical Committee
X David Pearson, Public Utilities X Annette, Planning
X Jesse Stewart, Public Utilities X Cooper, Police
Brad Stewart, Public Utilities X Ron Fife, Fire Department
X Jack, SLC Engineering X Peter, Sustainability
NEW BUSINESS:
1. Goal:
o How to spend the budget within
▪ The next 5-10 years
▪ What is needed to budget and how to prioritize
2. Planning (Annette filling in for Mayara)
o Design and color of the streetlights fit within the neighborhood
• Historic Districts
• Rose Park
• Poplar Grove
o Color meaning: the LED color temperature and the color of the poles/luminaries
o Day time aesthetics
▪ No planning master plans include streetlights currently
▪ Need to double check to make sure if there is any overlap
o Conflict between districts if they do not get the same thing?
▪ Historic districts are treated completely differently than others
▪ Guidelines for street lighting in historic districts
o Have the street lighting master plan acknowledge the design guidelines
o Review the historic districts and guidelines
o Other districts:
▪ Downtown district
o Districts vs. neighborhoods
▪ Rose park and poplar grove are known for their street trees
▪ These should be on the website
▪ Maybe already in GIS
o Make sure to get those layers in GIS
3. Engineering
o What existing programmatic controls does the city have that protect the existing streetlight
utility/ power supply?
o As more lights get installed, what can be done to make sure that the power supply is
protected?
o Subsurface in the right of way is getting really crowded
65
APPENDIX Bo Currently the lines are not in Blue Stake
o Is it practical/room for improvement on location of lines?
o As time/budget allows, possibility to move the lines into blue stake
▪ This would keep survey crews busy for about 2 years
▪ This would lie more in implementation vs. master plan
▪ Important to note in recommendations of how to move forward
4. Sustainability
o Energy 2040
▪ 80% reduction in our Green House Gases by 2040 (community wide for the whole city)
▪ 50% renewable energy goal by 2020
▪ Baseline is 2009
o Updating Climate response plans
o Solar Street Light just received
▪ On a cul-de-sac off 2700 S testing
o Solar Roadways
▪ Lot of progress in Europe and a company in Idaho
o Slowed wholesale replacements until this master plan is complete
▪ Replacing as needed but not overhaul now
o What % of the City’s energy does Street light make up?
o Strategies:
▪ LED obvious
▪ Dimming
▪ Lumens/watt
o Technology, part of our perception
o Dimmable LED’s at 17th and 17th
▪ Maybe run a test program and dim the lights down to 50% for a week then possibly dim
down to 25%
o Dark Sky
5. Police
o Evidence Preservation
o Preventing Crime
o Controlling Crime
o Smart Lighting
▪ Help a lot with tactical teams to go into a standoff – control the lighting on that block
would be immensely important and helpful
▪ Dimming down and making brighter both could be helpful
▪ Dave can give Police and Fire log in to Smart Lights to be able to control on their own
when needed
▪ Gunshot detection
▪ Lead the fire truck
▪ Citizens are asking for it too
o Opportunities
▪ Brighten up when Jazz game lets out
▪ Lower the lights during snowstorm
▪ Over design for brighter level and dim?
▪ Or overdrive the LEDs for short period of time during when you want them up
• What are those cost implications?
o Lighting for the sidewalks in different neighborhoods
o Support LED because of the color rendering for victims and witnesses to identify colors of
cars and suspects
o Trees block a lot of the light in different neighborhoods
o Even/consistent lighting throughout neighborhoods
o Lots of midblock lights are blocked by the trees
o Acorn lights - because of the way they light
▪ A lot of glare
▪ The way it glares it creates a blind spot especially right at the pole
o Stop the light right at the back of the sidewalk
▪ Glare makes it nearly impossible to see anything from a camera
o Distribution of light
6. Fire
o Inclusive with police
o Uneven light when responding can lead to inability to see pedestrians and cars
66
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
▪ Even light help the drivers see vehicle and pedestrians
▪ Evening lighting on the street and approach at a minimum to get where they need to be
without obstruction
o On seen
▪ Visualizing the addresses
▪ Ongoing issue
▪ Maybe hard to address with street lighting
▪ Able to illuminate the seen if needed see obstacles
▪ People step in holes because they cannot see where they are going,
▪ Focused on the issue they are there to solve
End of meeting notes.
APPENDIX B
67
Salt Lake City –Existing Street Lighting Conditions February 2019 1
Existing Street Lighting Conditions
Salt Lake City, Utah
Salt Lake City –Existing Street Lighting Conditions February 2019 2
EXECUTIVE SUMMARY
Salt Lake City requested an evaluation of the existing street lighting conditions and a Master Plan to aid in transitioning
the remainder of the street lighting from a high pressure sodium system to an LED system and implement a lighting
control system,with the intent to improve visibility and aesthetics while reducing energy and maintenance. The Master
Plan develops new street lighting standards for retrofit and new construction.To obtain a comprehensive understanding
of the existing lighting, Clanton & Associates surveyed seventeen locations within the city,conducted nighttime surveys,
and calculated the light levels along primary arterial,minor arterial, collector and local streets.From these evaluations,
existing condition templates were created to aid the city in prioritizing improvement areas which will influence street
lighting retrofits.By enhancing the street lighting, the city will promote a higher standard of well being as well as a more
comfortable place for residents and commuters.
Evaluation of Existing Lighting Conditions
In November 2018,Clanton & Associates evaluated the current lighting conditions at seventeen sites around the city that
provided an understanding of the diversity of lighting conditions. The selected sites included arterial, collector and local
streets with industrial, commercial,and residential areas.Both horizontal and vertical illuminance
1measurements were
taken along the sidewalks at each site. Luminance
2 measurements were also taken to provide an understanding of
surrounding surface brightness. These measured light levels were used to compare the existing light levels to the light
level recommendations by the Illuminating Engineering Society (IES). Clanton & Associates also took high-dynamic-
range (HDR)images as a visual representation of the perceived nighttime experience.Along with the lighting
measurements, the Advisory and Technical Committees completed a subjective survey assessing the lighted
environment at each site. The survey evaluated how each participant felt about the lighting strategies and overall light
levels at each site as well as how comfortable participants were at the sites. The survey results will be compared to
existing light levels and lighting criteria to guide the development of the Street Lighting Master Plan and the lighting
standards included in it. The site evaluations,and lighting measurements can be found in this report.
Street Lighting Levels
To understand the street lighting throughout the entire city,Clanton & Associates will calculate light levels on arterial,
collector and residential streets. These calculations will be compared to existing street lighting GIS data to determine
how well roadways were lighted.Street blocks will be categorized into three levels of acceptability based on the
calculations, lamp wattage, street type,luminaire spacing,and by comparing measure lighting levels to IES standards.
Acceptable:Streets that met the lighting standards based on street classification with existing luminaire spacing.
These areas would not require any lighting improvements beyond the LED retrofit assuming all current luminaires
are operating properly.
Moderately Acceptable:Streets that do not meet lighting standards based on street classification with existing
luminaire spacing.Typically,these are blocks that have relatively small dark spaces between poles and would
require minor improvements in order to meet lighting standards.
Poor:Streets that have very low,or no,street lighting. These are blocks that typically do not have enough existing
street lights and will most likely require significant investment in new lighting and electrical infrastructure to meet
lighting standards.
Lighting Improvements
Lighting improvements in Salt Lake City will enhance lighting on arterial,collector and residential streets by classifying
each street,setting standards and guidelines for street lighting retrofit and new construction projects.Well lit streets will
help to reduce vehicle accidents as well as pedestrian/vehicle conflicts. Various character districts will be designated
throughout the city in order to provide cohesive and quality lighting based on the surrounding environment. Vertical light
levels will also be increased to enhance pedestrian and object visibility.LED luminaires consume significantly less
energy and require far less maintenance than traditional lighting systems resulting in a quick return on investment.
Executive Summary Existing Conditions Example
3.5
0.1
0.9
cd/m2
The following High Dynamic Range images (HDR)and measured illuminance levels were taken during the
November 2018 site visit.An analysis of the seventeen sites surveyed can be found in this report.
1000E 2100S–Acceptable (1.76 average luminance)
1900E & Sunnyside –Unacceptable (0.41 average luminance)
Measured Illuminance Levels
Criteria Acceptance Level Luminance Type (cd/m^2)Street Luminance
Arterial Street Criteria Acceptable Average 0.9
1000E. 2100S.Acceptable Average 1.76
1900S. Sunnyside Unacceptable Average 0.41
3.5
0.1
0.9
cd/m2
1 Illuminance: the amount of light reaching a surface, expressed in units of footcandles [fc]
2 Luminance: the amount of light reflected from a surface that the eye perceives, expressed in units of candela per
square meter [cd/m2]APPENDIX C
68
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
Salt Lake City –Existing Street Lighting Conditions February 2019 3
Street Classifications
Street Classifications Map
Salt Lake City –Existing Street Lighting Conditions February 2019 6
SITE EVALUATIONS
Surveys Conducted 04-01-2019APPENDIX C
69
Salt Lake City –Existing Street Lighting Conditions February 2019 7
INTRODUCTION
Four “Levels of Acceptability”were determined from an analysis of the site observations and survey
results: Excellent, Good, Moderate and Poor.
Excellent acceptability is obtained by providing sufficient and appropriate lighting on the roadway,while
also providing adequate vertical illumination to allow for object detection and facial recognition. The
lighting in this location will be relatively uniform,free of direct glare and properly illuminates the roadway
and sidewalk.
Good acceptability indicates that the lighting in the area feels comfortable.In some cases, such as
residential areas,the light level might be lower than the IES Recommended Practice but the lack of glare
and shadowing from surrounding landscaping, along with some surrounding surface brightness, creates a
comfortable nighttime environment without light trespass.
Moderate acceptability is often seen in locations that do not provide enough light on the roadway or on
the sidewalk. The color of the light may be inconsistent and sources may be glary resulting in a
uncomfortable space.Some of these sites were shadowed due to trees and lighting was not appropriately
spaced.
Poor acceptability occurs when the luminaires are spaced too far apart to provide adequate light levels
and uniformity or there are no luminaires on the street at all. These sites included residential areas
without sufficient light,industrial sites and an arterial road where lights were malfunctioning.
These levels of acceptability provide an understanding of the nighttime environments found throughout
the city.This allows a variety of lighting improvement options to be developed. These future lighting
options will enhance the nighttime safety and security around the city.Each option will focus on improving
light levels, uniformity,and wayfinding while reducing glare.700E. Harrison Daytime Environment700E. Harrison Nighttime Environment700E. Harrison High-Dynamic RangeThis Salt Lake City Street Lighting Study provides an understanding of the current
street lighting in seventeen different locations throughout the city. The sites were
surveyed by representatives from each of the seven council districts,as well as Salt
Lake City representatives from the Police,Fire,Engineering,City Planning,
Sustainability, Transportation,and Urban Forestry departments.
The sites were selected based on street type,arterial, collector,or residential,and on
their surrounding environments in the city,industrial, commercial, transit or residential.
The selected sites will help provide a collective understanding of the lighting and
environmental conditions found throughout the city.This study and the Street Lighting
Masterplan are limited to streets,sidewalks and pedestrian paths in the Public Right of
Way and do not include any privately owned lighting. The seventeen sites surveyed
asked about the street and sidewalk lighting conditions. Those sites included:
Establishing Levels of AcceptabilitySite Observations
Example of Good Residential Lighting Example of Poor Residential Lighting
Each site was photographed using High Dynamic Range photography techniques and
lighting measurements were recorded for the streets and sidewalks. Both horizontal and
vertical illuminance (the amount of light reaching a surface) measurements were taken
along the sidewalk. Luminance (the amount of light on a surface that the eye perceives)
measurements were taken along the roadway to provide an understanding of roadway
brightness at each site. These measured light levels were used to compare the existing
light levels to the light level recommendation from the IES Recommended Practice for
Roadway Lighting (RP-8-18).Clanton & Associates also took high-dynamic-range (HDR)
images as a visual representation of the perceived nighttime experience.An example,of
the images taken,is shown to the left.
After measurements were taken,the Advisory and Technical Committee were broken
into two groups and taken on a nighttime tour of the selected sites and asked to
complete a survey assessing the lighted environment. The survey was comprised of
several subjective questions regarding the safety and aesthetics of each site. The survey
includes,but was not limited to, the following questions:
•It would be safe to walk here, alone, during daylight hours.
•It would be safe to walk here, alone, during darkness hours.
•The light is uneven (patchy).
•The light sources are glaring.
•The lighting is poorly matched to the neighborhood.
Participants answered each question with a ranking between Strongly Agree and
Strongly Disagree. The answers to each question were combined to provide an
understanding of each site. Participants surveyed 11 different sites featuring arterial,
collector and residential streets in industrial, commercial and residential areas.
1.Sterling & American Beauty Dr.
2.600N & Riverside Park
3.Redwood Road & South Temple
4.700S & Post Street
5.900W & Dalton Ave
6.Glendale Dr. & Navajo St
7.Jay St & 1st Ave
8.800E & South Temple
9.200S & Floral St
10.650S & Main Street
11.700E & Harrison Ave
12.9th & 9th
13.Layton Ave & West Temple
14.1500S & Yale
15. 19
th E & Sunnyside
16.1400E & Redondo
17.1000E & 2100S
Salt Lake City –Existing Street Lighting Conditions February 2019 9
LIGHTING MEASUREMENTS AND SUBJECTIVE SURVEY SUMMARY
Site # Site Name Street Classification Existing
Lighting
Sterling & American
Beauty Dr.
Local / Residential Excellent
Riverside Park &
600N
Arterial / Park Acceptable
Redwood Rd &
South Temple
Collector / Industrial Poor
700S & Post Street Local / Residential Poor
900W & Dalton Ave Arterial / Residential Acceptable
Glendale Dr. &
Navajo St
Collector / Residential /
Commercial Moderate
J St & 2nd Ave Local / Residential Poor
800E & South
Temple
Arterial / Commercial Excellent
200S & Floral St Arterial / Commercial Excellent
650S & Main St Arterial / Commercial Acceptable
700E & Harrison
Ave
Arterial / Residential Poor
9th & 9th Arterial / Commercial Acceptable
Layton Ave & West
Temple
Local / Residential Moderate
1500S & Yale Collector / Residential Acceptable
19th E & Sunnyside Arterial / Residential /
Commercial Moderate
1400E & Redondo Local / Residential Moderate
1000E & 2100S Arterial / Commercial Acceptable
1
16
15
14
13
12
11
10
2
3
5
6
7
8
9
4
17
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
SLC Public Utilities
Excellent Site
Acceptable Site
Moderate Site
Poor Site
1000 North
I-80
Redwood RoadSouth Temple
400 South
900 South
1300 South
1700 South
Sunnyside Avenue
Footh
i
l
l
D
r
i
ve
1300 East700 EastState StreetI-15900 West1
2 APPENDIX CSite # Site Name Street
Classification
Existing
Lighting
Sterling & American
Beauty Dr. Local / Residential Excellent
Riverside Park
& 600 North Arterial / Park Acceptable
Redwood Rd.
& South Temple Collector / Industrial Poor
700 South
& Post Street Local / Residential Poor
500 West & Dalton
Ave.Arterial / Residential Acceptable
Glendale Dr. &
Navajo St.
Collector / Residential
/ Commercial Moderate
J St. & 2nd Ave.Local / Residential Poor
800 East & South
Temple Arterial / Commercial Excellent
200 South & Floral St.Arterial / Commercial Excellent
650 South & Main St.Arterial / Commercial Acceptable
700 East & Harrison
Ave.Arterial / Residential Poor
900 East & 900 South Arterial / Commercial Acceptable
Layton Ave. & West
Temple Local / Residential Moderate
1500 South & Yale Collector / Residential Acceptable
19th East & Sunnyside Arterial / Residential /
Commercial Moderate
1400 East & Redando Local / Residential Moderate
1000 East & 2100
South Arterial / Commercial Acceptable
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
70
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
Salt Lake City –Existing Street Lighting Conditions February 2019
Salt Lake City –Existing Street Lighting Conditions February 2019
-4.0 -3.0 -2.0 -1.0 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 12.0 13.0 14.0 15.0 16.0 17.0 18.0 19.0
Site 17
Site 15
Site 13
Site 11
Site 09
Site 07
Site 05
Site 03
Site 01
Summary of Surveys
-100%
-50%
0%
50%
100%
150%
200%
-10.0-8.0-6.0-4.0-2.00.02.04.06.08.010.012.014.016.018.020.0
Site 17Site 16Site 15Site 14Site 13Site 12Site 11Site 10Site 09Site 08Site 07Site 06Site 05Site 04Site 03Site 02Site 01Survey Evaluations w/ Percent of Critiera Site Score
% From Criteria
Site # Site Name Street Classification Existing
Lighting
Sterling & American
Beauty Dr.
Local / Residential Excellent
Riverside Park &
600N
Arterial / Park Acceptable
Redwood Rd &
South Temple
Collector / Industrial Poor
700S & Post Street Local / Residential Poor
900W & Dalton Ave Arterial / Residential Acceptable
Glendale Dr. &
Navajo St
Collector / Residential /
Commercial Moderate
J St & 2nd Ave Local / Residential Poor
800E & South
Temple
Arterial / Commercial Excellent
200S & Floral St Arterial / Commercial Excellent
650S & Main St Arterial / Commercial Acceptable
700E & Harrison
Ave
Arterial / Residential Poor
9th & 9th Arterial / Commercial Acceptable
Layton Ave & West
Temple
Local / Residential Moderate
1500S & Yale Collector / Residential Acceptable
19th E & Sunnyside Arterial / Residential /
Commercial Moderate
1400E & Redondo Local / Residential Moderate
1000E & 2100S Arterial / Commercial Acceptable
1
16
15
14
13
12
11
10
2
3
5
6
7
8
9
4
17APPENDIX C
71
Salt Lake City –Existing Street Lighting Conditions February 2019
Surveyed by: Group 1
Site : Sterling & American Beauty Dr
Local / Residential
1
Salt Lake City –Existing Street Lighting Conditions February 2019
-3
-2
-1
0
1
2
3
Sterling & American Beauty Dr
13
Green Bars are Positive Responses
Blue Bars are Negative Responses
3.5
0.0
cd/m2
Sidewalk Illuminance (fc)Roadway Luminance
(cd/m^2)Horizontal Vertical (min)
Local Criteria
Low Conflict
Average 0.4 0.1 0.3
Ave/Min 4 -6
Site 1 Average 0.2 0.0 0.1
Ave/Min 5.9 -1.9
Surveyed by: Group 1
1
1
Level of Acceptability: Excellent (Lighting Score = 17.5)
Sterling Dr is in Tier 1 of the Enhanced Lighting Program with acorn lights spaced at intersections and mid block.
Initial Site Observations
•Local Residential street in Rose Park neighborhood.
•Part of Enhanced Lighting Program Tier 1.
•Adjacent to Rose Park Elementary School
Lighting Measurements
•Street lighting does not meet criteria for a local road with a low pedestrian conflict.
•Low vertical light levels make it difficult for cars to identify pedestrians and objects in the roadway.
Participant Survey
•Participants said:
•“Great lighting for a residential area.”
•“This is nice lighting. A model for rest of city “
% From Criteria:
-36% Below
Site : Sterling & American Beauty Dr
Local / Residential APPENDIX C
72
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
Salt Lake City –Existing Street Lighting Conditions February 2019
Surveyed by: Group 1
Site : Riverside Park @ 600N
Arterial / Park
2
Salt Lake City –Existing Street Lighting Conditions February 2019
-3
-2
-1
0
1
2
3
Riverside Park @ 600N
15
3.5
0.0
cd/m2
Sidewalk Illuminance (fc)Roadway Luminance
(cd/m^2)Horizontal Vertical (min)
Arterial Criteria
Medium Conflict
Average 0.5 0.2 0.9
Ave/Min 4 -3
Site 2 Average 0.5 0.0 1.0
Ave/Min 15.8 -1.9
Surveyed by: Group 1
2
2
Level of Acceptability: Acceptable (Lighting Score = 9.8)
600N is lit with LED luminaires in a staggered arrangement and meets roadway lighting criteria.
Initial Site Observations
•This is a wide arterial road with heavy traffic from commuters and shipping.
•This site is located between Riverside Park and Backman Elementary School.
•Street lights are LED and arranged in a staggered arrangement.
Lighting Measurements
•This street meets the roadway luminance criteria for an arterial street with a medium pedestrian conflict.
•Horizontal illuminance on the sidewalks meets criteria, but vertical illuminance does not.
Participant Survey
•Participants felt the amount of light was good, however the style and color does not match the neighborhood.
•Participants found the light the be slightly glaring
% From Criteria:
14% Above
Site : Riverside Park @ 600N
Arterial / Park
Green Bars are Positive Responses
Blue Bars are Negative ResponsesAPPENDIX C
73
Salt Lake City –Existing Street Lighting Conditions February 2019
Surveyed by: Group 1
Site : Redwood Rd & S Temple
Collector / Industrial
3
Salt Lake City –Existing Street Lighting Conditions February 2019
Level of Acceptability: Poor (Lighting Score = -2.9)
S. Temple is lit with HPS luminaires in a staggered arrangement and does not meet roadway criteria.
Initial Site Observations
•This site is an industrial part of town next to a ABF Freight.
•There is no sidewalk on either side of the road and very minimal pedestrian traffic.
•S. Temple dead ends at private property to the east.
Lighting Measurements
•The street is under lighted and does not meet roadway criteria.
•The are currently no sidewalks, and light does not meet the edge of roadway where pedestrians would be
walking.
Participant Survey
•Participants were very uncomfortable with this site.
•Participants did not feel safe on this site during the day or night, due to the industrial location.
•Participants felt that there was not enough light at this site.
17
3.5
0.0
cd/m2
Sidewalk Illuminance (fc)Roadway Luminance
(cd/m^2)Horizontal Vertical (min)
Collector Criteria
Low Conflict
Average 0.3 0.08 0.4
Ave/Min 6 -4
Site 3 Average 0.1 0.0 0.2
Ave/Min 1.3 -2.3
Surveyed by: Group 1
3
3
-3
-2
-1
0
1
2
3
Redwood Rd & S Temple
% From Criteria:
-54% Below
Site : Redwood Rd & S Temple
Collector / Industrial
Green Bars are Positive Responses
Blue Bars are Negative Responses APPENDIX C
74
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
Salt Lake City –Existing Street Lighting Conditions February 2019
Surveyed by: Group 2
Site : 700S Post Street
Local / Residential
4
Salt Lake City –Existing Street Lighting Conditions February 2019 19
3.5
0.0
cd/m2
Sidewalk Illuminance (fc)Roadway Luminance
(cd/m^2)Horizontal Vertical (min)
Local Criteria
Low Conflict
Average 0.3 0.08 0.3
Ave/Min 6 -6
Site 4 Average 0.0 0.0 0.0
Ave/Min ---
Surveyed by: Group 2
-3
-2
-1
0
1
2
3
700S Post Street
4
4
Level of Acceptability: Poor (Lighting Score = -1.8)
700S is an extremely wide residential street with cobrahead style luminaires at intersections.
Initial Site Observations
•700S is an extremely wide residential street and was described by one resident as an “air strip.”
•The streets in this area are lit by HPS luminaires located at intersections. Current luminaires are not capable
of providing light across the wide intersections.
Lighting Measurements
•This street is dark and only lit by passing cars.
•There is no light on sidewalks except directly below luminaires.
Participant Survey
•Participants felt uncomfortable in this location at night, but very safe during the day, which indicates additional
lighting could be helpful.
•They felt strongly that there was not enough light on the roadway or sidewalk and were not able to identify
faces and colors.
% From Criteria:
-97% Below
Site : 700S Post Street
Local / Residential
Green Bars are Positive Responses
Blue Bars are Negative ResponsesAPPENDIX C
75
Salt Lake City –Existing Street Lighting Conditions February 2019
Surveyed by: Group 2
Site : 900W & Dalton Ave
Arterial / Residential
5
Salt Lake City –Existing Street Lighting Conditions February 2019
Level of Acceptability: Acceptable (Lighting Score = 5.2)
900W is an arterial street lit by HPS luminaires in a staggered arrangement.
Initial Site Observations
•This is a 5 lane arterial road next to Jordan Park.
•Luminaires are LED and are in a staggered arrangement.
•Sidewalks are separated from roadway by landscaping, but have sufficient horizontal illuminance.
Lighting Measurements
•Heavy traffic while measurements were being taken contributed to light levels.
•Roadway luminance measurements meet criteria, but street feels slightly underlit.
•Sidewalk horizontal criteria is met, but vertical illuminance is low.
Participant Survey
•Participants felt that the lighting was patchy and that trees obstructed light from hitting the sidewalks.
•Overall they felt that this wide street had good coverage, however light sources appeared glaring.
•Participants were split over if the sidewalks were sufficiently lit or not.
21
3.5
0.0
cd/m2
Sidewalk Illuminance (fc)Roadway Luminance
(cd/m^2)Horizontal Vertical (min)
Arterial Criteria
Low Conflict
Average 0.3 0.08 0.6
Ave/Min 6 -3.5
Site 5 Average 0.3 0.0 1.4
Ave/Min 2.9 -5.1
Surveyed by: Group 2
-3
-2
-1
0
1
2
3
900W & Dalton Ave
5
5
% From Criteria:
137% Above
Site : 900W & Dalton Ave
Arterial / Residential
Green Bars are Positive Responses
Blue Bars are Negative Responses APPENDIX C
76
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
Salt Lake City –Existing Street Lighting Conditions February 2019
Surveyed by: Group 2
Site : Glendale Dr. & Navajo St
Collector / Residential / Commercial
6
Salt Lake City –Existing Street Lighting Conditions February 2019
Level of Acceptability: Moderate (Lighting Score = 2.7)
Glendale Dr. is lit by HPS lights and also sees major contribution from nearby private lighting.
Initial Site Observations
•This is a residential/commercial area near the US Dream Academy and a Church.
•The street lighting is located midblock and at intersections, but private lighting from parking lots contribute to
light on the street and sidewalk.
•Building mounted lights are glaring and shine into residences across the street.
Lighting Measurements
•The roadway is under lighted, even with contribution from private lighting.
•The horizontal and vertical illuminance on the sidewalk does not meet criteria.
Participant Survey
•Participants felt that the lighting was patchy with different types and colors and several dark areas.
•Overall they were split over the nighttime conditions.
23
3.5
0.0
cd/m2
Sidewalk Illuminance (fc)Roadway Luminance
(cd/m^2)Horizontal Vertical (min)
Collector Criteria
Medium Conflict
Average 0.5 0.2 0.6
Ave/Min 4 -3.5
Site 6 Average 0.2 0.0 0.2
Ave/Min 1.5 -1.7
Surveyed by: Group 2
-3
-2
-1
0
1
2
3
Glendale Dr. & Navajo St
6
6
% From Criteria:
-60% Below
Site : Glendale Dr. & Navajo St
Collector / Residential / Commercial
Green Bars are Positive Responses
Blue Bars are Negative ResponsesAPPENDIX C
77
Salt Lake City –Existing Street Lighting Conditions February 2019
Surveyed by: Both Groups
Site : Jay St & 1st Ave
Local / Residential
7
Salt Lake City –Existing Street Lighting Conditions February 2019
Level of Acceptability: Poor (Lighting Score = -0.3)
2nd Ave is residential street lit by a single HPS luminaire at each intersection.
Initial Site Observations
•This site is located in a residential neighborhood adjacent to a Church.
•Sidewalks are separated from the road by landscaping and feel dark. Large trees shadow the sidewalks.
•Sidewalk adjacent to the Church has light contribution from parking lot lighting.
Lighting Measurements
•The luminance on 2nd Ave does not meet criteria for a local street, but the lighting layout is in accordance with
the current SLC Street Lighting Masterplan.
•Sidewalks are dark and do not have any light, except directly below luminaire.
Participant Survey
•Participants felt that the street light only sufficiently illuminates the intersection. The remaining roadway and the
sidewalks are dark.
•Participants were split on nighttime safety and comfort levels.
25
3.5
0.0
cd/m2
Sidewalk Illuminance (fc)Roadway Luminance
(cd/m^2)Horizontal Vertical (min)
Local Criteria
Low Conflict
Average 0.3 0.08 0.3
Ave/Min 6 -6
Site 7 Average 0.1 0.0 0.1
Ave/Min 9.9 -3.3
Surveyed by: Both Groups
-3
-2
-1
0
1
2
3
Jay St & 1st Ave
7
7
% From Criteria:
-67% Below
Site : Jay St & 1st Ave
Local / Residential
Green Bars are Positive Responses
Blue Bars are Negative Responses APPENDIX C
78
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
Salt Lake City –Existing Street Lighting Conditions February 2019
Surveyed by: Both Groups
Site : 800E & S. Temple
Arterial / Commercial
8
Salt Lake City –Existing Street Lighting Conditions February 2019
Level of Acceptability: Excellent (Lighting Score = 13.9)
S. Temple is lit using LED Acorn style luminaires arranged in an opposite arrangement.
Initial Site Observations
•S. Temple is a 4 lane arterial road connecting downtown, the avenues and the University.
•This is a commercial area with a restaurants, condominiums and businesses nearby.
•Sidewalks are separated from the street by landscaping and are shadowed by large trees. Additional pedestrian
lights are placed at crosswalks.
Lighting Measurements
•Heavy traffic while measurements were being taken contributed to light levels.
•Roadway luminance far exceeds criteria, but light levels felt appropriate for this street.
•Sidewalks are slightly below criteria, and there is some light contribution from nearby businesses.
Participant Survey
•Participants felt that the lighting at this sight was better than other similar site throughout the city.
•Participants were split on light levels. Some felt it was too bright, while others desired slightly more light.
27
3.5
0.0
cd/m2
Sidewalk Illuminance (fc)Roadway Luminance
(cd/m^2)Horizontal Vertical (min)
Arterial Criteria
Medium Conflict
Average 0.5 0.2 0.9
Ave/Min 4 -3
Site 8 Average 0.4 0.1 1.5
Ave/Min 3.0 -1.8
Surveyed by: Both Groups
8
-3
-2
-1
0
1
2
3
800E & S. Temple
8
% From Criteria:
65% Above
Site : 800E & S. Temple
Arterial / Commercial
Green Bars are Positive Responses
Blue Bars are Negative ResponsesAPPENDIX C
79
Salt Lake City –Existing Street Lighting Conditions February 2019
Surveyed by: Both Groups
Site : 200S Floral St
Arterial / Commercial
9
Salt Lake City –Existing Street Lighting Conditions February 2019
Level of Acceptability: Excellent (Lighting Score = 13.8)
200S is an arterial road running through the heart of downtown with cactus style poles.
Initial Site Observations
•This site is in the heart of downtown SLC nearby multiple bars and restaurants.
•Cactus style poles are closely spaced on both sides of the road.
•There is a large, non signalized, mid block crosswalk across 200S.
Lighting Measurements
•The roadway essentially meets criteria at this site and feels comfortable.
•The cactus poles use acorn style luminaires that provide good vertical illuminance on pedestrians.
•This site is essentially meets all criteria.
Participant Survey
•Participants felt that the lighting at this site was better then similar areas throughout the city.
•Participants felt that the light sources were glaring and light could be better directed toward the street.
•Participants also felt that the light fixtures meet the character of the area, but there are too many of them.
29
3.5
0.0
cd/m2
Sidewalk Illuminance (fc)Roadway Luminance
(cd/m^2)Horizontal Vertical (min)
Arterial Criteria
Medium Conflict
Average 0.5 0.2 0.9
Ave/Min 4 -3
Site 9 Average 0.8 0.5 0.8
Ave/Min 4.2 -1.7
Surveyed by: Both Groups
-3
-2
-1
0
1
2
3
200S Floral St
9
9
% From Criteria:
-8% Below
Site : 200S Floral St
Arterial / Commercial
Green Bars are Positive Responses
Blue Bars are Negative Responses APPENDIX C
80
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
Salt Lake City –Existing Street Lighting Conditions February 2019
Surveyed by: Both Groups
Site : 650S Main Street
Arterial / Commercial
10
Salt Lake City –Existing Street Lighting Conditions February 2019
Level of Acceptability: Acceptable (Lighting Score = 6.3)
Main St. is a collector street with a shared transit line, lit with LED luminaires in a staggered arrangement.
Initial Site Observations
•Main St. is shared by both vehicles and the TRAX line.
•North and Southbound lanes are separated by a large landscape median that supplies power for TRAX.
•Sidewalks are separated from the road by landscaping and are shaded by large trees.
Lighting Measurements
•The roadway exceeds criteria. Luminaires used are glaring.
•Sidewalk essentially meets criteria, but have significant contribution from private lighting.
•Overall, this site is well lit.
Participant Survey
•Participants felt that the trees blocked a lot of light to the sidewalks which caused the light to be uneven.
•Overall, participants felt that the roadway was sufficiently lighted.
31
3.5
0.0
cd/m2
Sidewalk Illuminance (fc)Roadway Luminance
(cd/m^2)Horizontal Vertical (min)
Collector Criteria
Medium Conflict
Average 0.5 0.2 0.6
Ave/Min 4 -3.5
Site 10 Average 0.4 0.1 1.3
Ave/Min 2.5 -1.6
Surveyed by: Both Groups
-3
-2
-1
0
1
2
3
650S Main Street
10
10
% From Criteria:
116% Above
Site : 650S Main Street
Arterial / Commercial
Green Bars are Positive Responses
Blue Bars are Negative ResponsesAPPENDIX C
81
Salt Lake City –Existing Street Lighting Conditions February 2019
Surveyed by: Group 2
Site : 700E Harrison Ave
Arterial / Residential
11
Salt Lake City –Existing Street Lighting Conditions February 2019
Level of Acceptability: Poor** (Lighting Score = -2.1)
700E is a large arterial road spanning the whole Salt Lake valley with heavy traffic.
Initial Site Observations
•700E is a 7 lane arterial road with heavy commuter and shipping traffic, along with bike lanes that runs
throughout the whole valley.
•The site is adjacent to Herman Franks Park and Liberty Park.
•The roadway is lit using LED luminaires in a staggered arrangement.
Lighting Measurements
•The roadway exceeds lighting criteria, but luminance levels feel appropriate for this size of street.
•Light on the sidewalk does not meet horizontal or vertical illuminance criteria, but heavy traffic provides
additional light.
Participant Survey
•**Lights on the west side of the roadway were not operational during surveys.**
•Overall, participants felt this site was dark and was worse than similar sites throughout the city.
33
3.5
0.0
cd/m2
Sidewalk Illuminance (fc)Roadway Luminance
(cd/m^2)Horizontal Vertical (min)
Arterial Criteria
Medium Conflict
Average 0.5 0.2 0.9
Ave/Min 4 -3
Site 11 Average 0.2 0.0 1.6
Ave/Min 1.7 -4.6
Surveyed by: Group 2
-3
-2
-1
0
1
2
3
700E Harrison Ave
11
11
** % From Criteria:
78% Above
Site : 700E Harrison Ave
Arterial / Residential
Green Bars are Positive Responses
Blue Bars are Negative Responses APPENDIX C
82
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
Salt Lake City –Existing Street Lighting Conditions February 2019
Surveyed by: Group 1
Site : 9th & 9th
Arterial / Commercial
12
Salt Lake City –Existing Street Lighting Conditions February 2019
Level of Acceptability: Acceptable (Lighting Score = 10.1)
900S is a collector street in a commercial area with by pedestrian style luminaires
Initial Site Observations
•9th & 9th is a bustling commercial area and a destination in Salt Lake.
•The streets and sidewalks are lit mostly by pedestrian style luminaires along with cobra heads mounted on
signal poles.
•Landscaping and on street parking separate the sidewalk from the roadway.
Lighting Measurements
•Overall, this site meets or exceeds the lighting criteria.
•The roadway luminance exceeds the target criteria, but luminance levels feel appropriate on the street.
•Sidewalk horizontal and vertical illuminance criteria is met.
Participant Survey
•Participants felt that this site was appropriately lit and was better than similar sites throughout the city.
•Participants noted that lighting could be better controlled and less glaring.
•Participants liked the style of lighting for the neighborhood character.
35
3.5
0.0
cd/m2
Sidewalk Illuminance (fc)Roadway Luminance
(cd/m^2)Horizontal Vertical (min)
Collector Criteria
Medium Conflict
Average 0.5 0.2 0.6
Ave/Min 4 -3.5
Site 12 Average 0.5 0.3 1.2
Ave/Min 5.6 -2.0
Surveyed by: Group 1
-3
-2
-1
0
1
2
3
9th & 9th
12
% From Criteria:
101% Above
Site : 9th & 9th
Arterial / Commercial12
Green Bars are Positive Responses
Blue Bars are Negative ResponsesAPPENDIX C
83
Salt Lake City –Existing Street Lighting Conditions February 2019
Surveyed by: Both Groups
Site : Layton Ave & W Temple
Local / Residential
13
Salt Lake City –Existing Street Lighting Conditions February 2019
Level of Acceptability: Moderate (Lighting Score = 3.6)
West Temple is a collector road passing through residential area lit with HPS Luminaires along one side of the road.
Initial Site Observations
•West Temple is a 2 lane collector road passing through a residential area lit with HPS lights along the east side
of the road.
•Large, dense trees block most of the light from hitting the roadway or sidewalk.
Lighting Measurements
•Due to the large trees, most of the light does not reach to ground, causing the roadway and sidewalks to be
under lighted.
•Sidewalks feel dark is dramatic shadowing from trees.
Participant Survey
•Participants were split on how appropriate the roadway and sidewalk lighting was.
•Participants were also split on nighttime safety and comfort levels at this site.
•Overall, this is a very polarizing site.
37
3.5
0.0
cd/m2
Sidewalk Illuminance (fc)Roadway Luminance
(cd/m^2)Horizontal Vertical (min)
Collector Criteria
Low Conflict
Average 0.3 0.08 0.4
Ave/Min 6 -4
Site 13 Average 0.1 0.0 0.2
Ave/Min 6.5 -10.1
Surveyed by: Both Groups
-3
-2
-1
0
1
2
3
Layton Ave & W Temple
13
13
% From Criteria:
-50% Below
Site : Layton Ave & W Temple
Local / Residential
Green Bars are Positive Responses
Blue Bars are Negative Responses APPENDIX C
84
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
Salt Lake City –Existing Street Lighting Conditions February 2019
Surveyed by: Group 1
Site : 1500S Yale Ave
Collector / Residential
14
Salt Lake City –Existing Street Lighting Conditions February 2019
Level of Acceptability: Acceptable (Lighting Score = 6.0)
1500S is a collector road bordering neighborhoods with Enhanced and base level lighting.
Initial Site Observations
•This site has both cobrahead HPS lights as well as acorn style lights that are part of the Enhanced Lighting
Program.
•1500S is a collector street connecting multiple residential areas with private and enhanced street lighting.
Lighting Measurements
•The street is slightly below criteria, but feels appropriate in this area.
•Sidewalk lighting does not meet horizontal or vertical criteria.
•Overall the site does not meet criteria, but feels lighting feels appropriate to the area.
Participant Survey
•Participants were divided on if the lighting was better or worse compared to similar areas, however they did
generally agree that this street might need additional lighting.
•Overall, participants felt that this site could use additional light.
•Survey was taken in a different location than the measurements were.
39
3.5
0.0
cd/m2
Sidewalk Illuminance (fc)Roadway Luminance
(cd/m^2)Horizontal Vertical (min)
Collector Criteria
Low Conflict
Average 0.3 0.08 0.4
Ave/Min 6 -4
Site 14 Average 0.2 0.0 0.3
Ave/Min 5.5 -8.4
Surveyed by: Group 1
-3
-2
-1
0
1
2
3
1500S Yale Ave
14
14
% From Criteria:
-37% Below
Site : 1500S Yale Ave
Collector / Residential
Green Bars are Positive Responses
Blue Bars are Negative ResponsesAPPENDIX C
85
Salt Lake City –Existing Street Lighting Conditions February 2019
Surveyed by: Group 1
Site : 19th E & Sunnyside Ave
Arterial / Residential / Commercial
15
Salt Lake City –Existing Street Lighting Conditions February 2019
Level of Acceptability: Moderate (Lighting Score = 2.2)
Sunnyside Ave is an arterial street connecting the residential neighborhoods with the University and Foothills.
Initial Site Observations
•This 5 lane arterial street is lit with LED lights from the north side of the road at a large spacing.
•The side borders residential neighborhoods, Sunnyside Park, a church, University housing and is a major path
into the University of Utah campus and to downtown.
•Lights are glaring and cause light trespass at residences across the street.
Lighting Measurements
•Both the sidewalk and roadway are under lighted and do not meet criteria.
•Lights are spaced too far apart and overly bright and glaring luminaires are used to help get light across and
down the street.
Participant Survey
•Participants felt that the lighting was insufficient on the south side of the road, due to the single-side lighting
arrangement.
•Overall, participants felt that this lighting was worse than similar areas and could use additional light.
41
3.5
0.0
cd/m2
Sidewalk Illuminance (fc)Roadway Luminance
(cd/m^2)Horizontal Vertical (min)
Arterial Criteria
Medium Conflict
Average 0.5 0.2 0.9
Ave/Min 4 -3
Site 15 Average 0.1 0.0 0.4
Ave/Min 5.7 -2.3
Surveyed by: Group 1
-3
-2
-1
0
1
2
3
19th E & Sunnyside Ave
15
15
% From Criteria:
-55% Below
Site : 19th E & Sunnyside Ave
Arterial / Residential / Commercial
Green Bars are Positive Responses
Blue Bars are Negative Responses APPENDIX C
86
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
Salt Lake City –Existing Street Lighting Conditions February 2019
Surveyed by: Group 2
Site : 1400E Redondo Ave
Local / Residential
16
Salt Lake City –Existing Street Lighting Conditions February 2019
Level of Acceptability: Moderate (Lighting Score = 3.2)
Redondo Ave is a residential street in the Sugarhouse area with private street lighting.
Initial Site Observations
•Redondo Ave is a residential street with private acorn style street lights.
•Multiple lights along the street were burnt out or malfunctioning.
•Large trees on the street shaded most of the lights.
Lighting Measurements
•This site does not meet roadway or sidewalk criteria.
•The infrastructure for decent street lighting is present, but multiple lights were not on resulting in a dark street.
Participant Survey
•Some participants felt that the light sources were glary, and provided patchy, insufficient light coverage.
•Participants liked the style of lights, but they did not feel comfortable, and would like to see more light on the
roadway and sidewalk.
43
3.5
0.0
cd/m2
Sidewalk Illuminance (fc)Roadway Luminance
(cd/m^2)Horizontal Vertical (min)
Local Criteria
Low Conflict
Average 0.3 0.08 0.3
Ave/Min 6 -6
Site 16 Average 0.1 0.0 0.0
Ave/Min 5.3 --
Surveyed by: Group 2
-3
-2
-1
0
1
2
3
1400E Redondo Ave
16
16
% From Criteria:
-48% Below
Site : 1400E Redondo Ave
Local / Residential
Green Bars are Positive Responses
Blue Bars are Negative ResponsesAPPENDIX C
87
Salt Lake City –Existing Street Lighting Conditions February 2019
Surveyed by: Group 2
Site : 1000E 2100S
Local / Commercial
17
Salt Lake City –Existing Street Lighting Conditions February 2019
Level of Acceptability: Acceptable (Lighting Score = 12.0)
2100S is in the heart of the Sugarhouse business district and is part of the Special Assessment Lighting program
Initial Site Observations
•The site is in the middle of the Sugarhouse business district and is surrounded by commercial properties.
•The luminaires used at this site have a street light as well as two pedestrian level light sources.
•2100S is a four lane arterial road and luminaires are in an opposite arrangement.
•Acorn style luminaires are bright and slightly glaring.
Lighting Measurements
•There is a lot of light at this site and all criteria is exceeded.
•Multi-head luminaires with street and pedestrian luminaires plenty of light on the sidewalk and street.
Participant Survey
•Most participants felt that there was too much light, and that the light sources were glaring.
•Overall, participants felt safe at this location.
45
3.5
0.0
cd/m2
Sidewalk Illuminance (fc)Roadway Luminance
(cd/m^2)Horizontal Vertical (min)
Collector Criteria
Medium Conflict
Average 0.5 0.2 0.6
Ave/Min 4 -3.5
Site 17 Average 2.5 0.3 1.8
Ave/Min 8.2 -2.6
Surveyed by: Group 2
-3
-2
-1
0
1
2
3
1000E 2100S
17
17
% From Criteria:
194% Above
Site : 1000E 2100S
Local / Commercial
Green Bars are Positive Responses
Blue Bars are Negative Responses APPENDIX C
88
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
THIS PAGE LEFT INTENTIONALLY BLANK
89
APPENDIX D
Salt Lake City Street Lighting Master Plan
Nocturnal Infrastructure for Ecological Health
Prepared by: Travis Longcore, Ph.D.
Prepared for: Clanton and Associates, Boulder, Colorado
May 2020
Lights of Salt Lake City wash out the Milky Way viewed from Antelope Island State Park.
Photograph: Ryan Andreasen.
90
SALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 1
Table of Contents
1 Introduction ............................................................................................................................. 1
2 Potential Impacts of Streetlights on Wildlife in Salt Lake City .............................................. 4
2.1 Physical Geography ........................................................................................................ 4
2.1.1 Great Salt Lake Shorelands ..................................................................................... 5
2.1.2 Jordan River ............................................................................................................ 7
2.1.3 Urban Creeks .......................................................................................................... 7
2.1.4 Wasatch Mountains ................................................................................................. 8
2.2 Sensitive Species ............................................................................................................. 8
2.3 Effects of Lighting on Key Wildlife Groups ................................................................ 10
2.3.1 Attraction and Disorientation ................................................................................ 10
2.3.2 Loss of Connectivity ............................................................................................. 12
2.3.3 Foraging ................................................................................................................ 13
2.3.4 Interference with Visual Communication ............................................................. 14
2.3.5 Physiological Responses ....................................................................................... 14
3 Consideration of Spectrum in Municipal Street Lighting Systems ...................................... 16
3.1 Effects on Wildlife ........................................................................................................ 16
3.2 Effects on Dark Skies .................................................................................................... 19
3.3 Human Circadian Rhythms ........................................................................................... 22
4 Design Strategies for a Healthy Nocturnal Infrastructure ..................................................... 27
4.1 Systemwide Approaches ............................................................................................... 27
4.1.1 Need-based Lighting ............................................................................................. 27
4.1.2 Shielding and Directionality ................................................................................. 27
4.1.3 Intensity, Dimming, and Controls ......................................................................... 27
4.1.4 Spectrum ............................................................................................................... 28
4.2 Ecological Overlay Strategies ....................................................................................... 30
4.2.1 Bird Collision Zone............................................................................................... 32
4.2.2 Critical Wildlife Habitat Zone .............................................................................. 32
4.2.3 Jordan River and Urban Creeks ............................................................................ 33
4.2.4 Community Parks and Natural Lands ................................................................... 33
5 References ............................................................................................................................. 34 APPENDIX D
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1 Introduction
Salt Lake City is located in a region connected to its night sky. The awe and wonder inspired by
a view of the Milky Way and sky overflowing with stars attracts visitors to Utah and contributes
to the identity of the region for residents. Salt Lake City itself is brightly illuminated, with its
cultural and institutional centers, commercial zones, and unique urban design. But just north of
the city, Antelope Island State Park has sought and received recognition as a Dark Sky Park by
the International Dark-Sky Association,
joining eight other Dark Sky Parks, a Dark
Sky Community, and a Dark Sky Heritage
Place in Utah (Figure 1). The future of
Antelope Island’s long-term status as a
Dark Sky Park depends on the decisions of
the cities along the Wasatch Front in
protecting the night sky (see cover).
Cities set the tone for night lighting in a
region. They are the most brightly lit, and
their size influences the markets, practices,
and professionals in a region. Commercial
zones of cities and towns tend to
contribute the most light escaping upward
(and therefore wasted), along with lighted
sports fields when they are illuminated
(Luginbuhl et al. 2009). Historically,
street lights contributed a significant and
constant amount to both useful and wasted
light through the night, while residential
lights and lighting from vehicles declines
substantially through course of the night
(Bará et al. 2017). Within residential
zones, most of the light is from the
streetlighting system, especially later in the evening when traffic rates are low and ornamental
lighting is switched off (Bará et al. 2017). Decisions made at municipal level about its street
lighting system therefore have a large contribution to the overall amount of useful and wasted
light in a city. Because perception of lighting is based on contrasts (the same light appears dim
next to a brighter source and bright next to a dimmer source), the decisions made in terms of
municipal street lighting systems have ramifications to the nocturnal environment that extend
beyond the system itself. As a metropolitan area, compared with the 125 largest metropolitan
areas in the United States, Salt Lake City is well above average in terms of the average amount
of light escaping upward that can be measured by satellites (Figure 2). It does not waste as much
light as other larger cities with their greater areas, but on a per area basis it contributes more to
regional light pollution than the average city, although not so much as New Orleans, which is a
similar size.
Figure 1. Distribution of recognized dark sky
places in and near Utah. Circles are Dark Sky
Parks, triangles are Dark Sky Communities, and
diamonds are Dark Sky Heritage Sites. Source:
List of Dark Sky Places maintained by Dark Skies
Advisory Group, IUCN. APPENDIX D
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Figure 2. Light escaping upwards from Salt Lake City 2012–2017 within the 125 largest
metropolitan regions in the United States. Top: radiance normalized for area. Bottom: total
radiance from entire city extent. Data from VIIRS DNB as analyzed by Horton et al. (2019).
Large-scale transformations of municipal street lighting systems have occurred over the past
decade as older lighting technologies have been replaced by light emitting diode (LED) systems.
Because of the history of the technology, where the early high-efficiency LEDs had a high
content of blue light, residents of many jurisdictions objected to the new lights. The bluish-white
light of LEDs in those installations was perceived as brighter because of the visual sensitivity of
the human eye to the greater proportion of shorter (blue) wavelengths in the light produced. In
addition, when lights are more efficient and less expensive to operate, there is a tendency to use
more light (Kyba et al. 2014). Not only does the color of light affect how humans perceive the
lights; the color of lights is recognized as influencing the contributions lights have to light
pollution (Aubé et al. 2013, Kinzey et al. 2017), wildlife (Longcore et al. 2015b, Donners et al.
2018, Longcore 2018), and human health (Garcia-Saenz et al. 2018).
Researchers and engaged lighting designers are developing techniques to minimize undesirable
effects of outdoor lighting on both astronomical and ecological light pollution. These include
guidance for protected lands (Longcore and Rich 2017), recommendations for specific groups of
species (Voigt et al. 2018), and recommendations balancing human vision and wildlife impacts
(Longcore et al. 2018a). As Salt Lake City prepares a new Street Lighting Master Plan, this
research can be synthesized and applied to inform decisions about the design of the future street
lighting system that is consistent with the values embodied in the plan. Mean RadianceSummed Radiance0
10
20
30
40
50
0
200000
400000
600000
800000
1000000
1200000
New York
Chicago
Los Angeles
Las Vegas
Salt Lake City
New Orleans
New York
Chicago
Los Angeles
Las Vegas
Salt Lake City New Orleans
0 20 40 60 80 100 120
Area RankAPPENDIX D
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3
This report provides guidance for minimizing the adverse impacts of unnecessary light at night
on species, habitats, and ecosystems in the development of a Street Lighting Master Plan for Salt
Lake City. The organization of the report is as follows. In the next chapter, the potential
impacts of street lighting on wildlife in Salt Lake City are reviewed, based on the published
scientific research. The following chapter explores the role of spectrum in determining the level
of impact on dark skies, circadian rhythms, and wildlife. Then, this information is synthesized in
a chapter outlining spatially explicit design strategies to reduce adverse impacts of street lighting
on sensitive biological resources within the context of the further development of Salt Lake
City’s municipal lighting system. With these strategies, Salt Lake City can build a nocturnal
infrastructure that supports ecological health by providing high-quality lighting for human safety
and well-being while protecting the night sky and nighttime environment within the city and
across the region, setting an example for others to follow. APPENDIX D
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2 Potential Impacts of Streetlights on Wildlife in Salt Lake City
Street lighting has a large spatial footprint within the area of a city. For a medium-sized city like
Salt Lake City, street lighting is provided throughout its residential, commercial, and industrial
districts to different extents. In this chapter, the potential effects of this system on wildlife are
considered, which requires assessment of the geographic extent of the city.
To describe the environment potentially affected by lighting in Salt Lake City, the physical
geography and habitats of the city were described and lists of sensitive species were compiled.
Together, these natural features and species distributions can provide the background to devise
spatially explicit schemes to minimize potentially adverse effects.
Figure 3. Location of Salt Lake City within the physical geography of the region (USGS
topographic maps, 1885, from http://historicalmaps.arcgis.com/usgs/).
2.1 Physical Geography
Salt Lake City is located on lacustrine terraces between the Wasatch Mountains and the Great
Salt Lake. It grew up as a central location for travel, commerce, and mining, supported by a
swath of irrigated lands extending north-south along the Wasatch Mountains. Although other
regional cities were established first (e.g., Ogden), Salt Lake City arose as the most significant
city through a confluence of its irrigation resources and its importance as a religious center. APPENDIX D
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The growth of Salt Lake City depended in part on the array of some 35 streams that flowed
downward from the Wasatch Mountains to the rich soils of the terraces above the Great Salt
Lake (Harris 1941). These streams were not deeply incised and therefore they could be diverted
for irrigation, compared with the rivers of the region, which although larger, are incised into
canyons and consequently could not be used easily be irrigation by the white settlers in the
1840s. The climate is mild, with a long growing season extended by proximity to the Great Salt
Lake. Snow accumulation in the mountains and a long melt season made agriculture attractive
and productive within the region. The creeks flowing out of the Wasatch Mountains, City Creek,
Red Butte Creek, Emigration Creek, Parley’s Cañon Creek (now Parley’s Creek), Big
Cottonwood Creek, in turn flowed into the Jordan River, which flowed northward to debouche
through a small distributary delta into the Great Salt Lake (Figure 3). The Jordan River has a
winding, low-gradient pathway that remains to this day, dividing the territory of the city into
eastern and western halves. The eastern half is characterized by the rising terraces climbing up
toward the mountains with the remaining extents of the westward-flowing creeks, while the
western portion of the city is an almost entirely flat open plain extending toward the shore of the
Great Salt Lake (Figure 3).
These features of the physical geography of Salt Lake City are a useful organizing framework to
discuss zones that remain important to the ecology and sensitive species of the City today: 1) the
Salt Lake shorelands, 2) the Jordan River, 3) the urban creeks, and 4) the Wasatch Mountains.
Figure 4. Example of the open landscape of the Great Salt Lake shorelands. Photo from Google
Local Guide Neil Martin, looking due east toward Salt Lake City.
2.1.1 Great Salt Lake Shorelands
The shorelands surrounding the Great Salt Lake extend far into the City limits of Salt Lake City.
The airport and western commercial and industrial areas extend into this zone. These flat, open
areas are made up of deep lacustrine sediments of clay and loam (Flowers 1934). Although the
vegetation changes by zones extending away from the lake, the plains and ponds within them
tend to be saline, which leads to a flora free from trees and dominated by low succulent herbs
and low shrubs, such as pickleweed, salt bush, salt grass, and seepweed (Flowers 1934). Open
habitats such as these (Figure 4) are vulnerable to disruption by light pollution because light
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(De Molenaar et al. 2006, Longcore and Rich 2017). Birds in landscapes like this can be
influenced by the direct glare from streetlights and will locate nests farther from lights when
such sites are available (De Molenaar et al. 2006).
These shoreland ecosystems are extremely important to shorebirds for foraging and breeding.
The brine shrimp and salt flies that feed on algae in and around the lake provide food and the
undisturbed open areas are used by Snowy Plovers, American Avocets, Black-necked Stilts,
Long-billed Curlew, and dozens of other shorebird and waterbird species (Jones 2008). A
portion of this area with Salt Lake City has been established and managed as the Inland Sea
Shorebird Reserve by Rio Tinto/Kennecott as mitigation for impacts from its nearby mining
operations. They took advantage of existing shallow depressions with soils high in clay that
naturally held water and managed the drainage system to extend inundation times and provide
high-quality bird habitat. The 3,670-acre reserve provides habitat for around 120,000 birds
annually.
The Great Salt Lake as a whole has been recognized as a site of “hemispheric importance” within
the Western Hemisphere Shorebird Network (Andres et al. 20016). Nearly all the western
shorelands with Salt Lake City have been designated as Very Important Bird Areas (IBAs) by
Birdlife International. They are the Gilbert Bay/South Arm IBA and the Farmington Bay IBA,
which each extend into and cover the undeveloped reaches of the shorelands. These IBAs are of
global importance (the highest possible ranking).
Figure 5. Extent of globally significant Important Bird Areas (blue) in Salt Lake City with City
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Figure 6. Example of the vegetation of the Jordan River as it winds through Salt Lake City.
Image from Google Local Guide Ross Pincock.
2.1.2 Jordan River
The Jordan River is a low-gradient, meandering river that
flows north to south through Salt Lake City. Considerable
development has affected the banks and floodplain, but
recent years have brought attention and restoration efforts to
enhance the river, its habitats, and its water quality.
The Jordan River supports riparian (streamside) habitats that
are used for nesting by neotropical migratory bird such as
Bullock’s Oriole, Willow Flycatcher, and Yellow-breasted
Chat, all of which nest along the Jordan River and then
migrate to Central America for the winter.
The Tracey Aviary conducts surveys and nest monitoring
along the Jordan River and birding hotspots along the river
include Glendale Golf Course, Jordan River Parkway (200 S
to 2100 S), Fife Wetlands Preserve, and Rose Park Golf
Course.
2.1.3 Urban Creeks
Salt Lake City has a series of creeks that flow down from the
Wasatch Mountains and cut east to west across the city
toward the Jordan River (Figure 7). Over time, the lower
extents of these creeks have been undergrounded, cutting off
the surface flows and diverting them to underground pipes.
For example, City Creek, was undergrounded along North
Temple Street in 1909 (Love 2005). These creeks have been
the focus of daylighting and restoration activities that may
Figure 7. Footprint of the
Jordan River running south to
north through the center of Salt
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extend into the future (Love 2005). Because of the water flows and support of riparian
vegetation, the remaining aboveground creeks remain important habitats for wildlife. They are
now surrounded by neighborhoods and receive heavy recreational use and provide valuable
access to nature within the urban fabric (Figure 8).
Figure 8. Image of Emigration Creek as it flows through the Wasatch Hollow Open Space. Photo
by Google Local Guide Joseph Muhlestein.
2.1.4 Wasatch Mountains
The foothills of the Wasatch Mountains to the
west of the Salt Lake City are contiguous with a
large block of contiguous open space and
wilderness area and therefore are easily
recognized as being environmentally sensitive.
One of the vulnerabilities of mountainous habitats
to light pollution is that their slopes are directly in
the light of sight for any light that is emitted
upward from nearby sources (Longcore and Rich
2017). Any light from Salt Lake City that is
emitted above the horizontal plane and directed
toward the east has the potential to degrade the
habitats of the Wasatch Mountains.
2.2 Sensitive Species
Important wildlife species of Salt Lake City were
reviewed in a 2010 program for the acquisition of
natural lands. The program identified and mapped
the distribution of critical habitat for wildlife. A
list of species for which potential habitat is found
in the City was also provided. This map identified
all parcels within the city that intersected with
areas that had potential habitat for Black Bear, Band-
Figure 9. Four urban creeks (purple)
extending out of the Wasatch Mountains
into Salt Lake City. APPENDIX D
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tailed Pigeon, Blue Grouse, Chukar Partridge, Moose, Mule Deer, Ring-necked Pheasant, Rocky
Mountain Elk, Ruffed Grouse, or Snowshoe Hare. The resulting map forms a ring around the
core of Salt Lake City, with critical wildlife habitat extending down the slopes of the Wasatch
range to the urban edge on the east and also enveloping the shorelands and extending from the
west to and around the north of the airport (Figure 10).
The city also has potential habitat for a range of sensitive plant and wildlife species. These
species include birds of the open shorelands (Bobolink, Burrowing Owl, Long-billed Curlew,
Northern Goshawk, Short-eared Owl) those associated with the foothills and creeks (Lewis’s
Woodpecker, Three-toed Woodpecker, Greater Sage Grouse, and some found throughout (e.g.,
Ferruginous Hawk, Grasshopper Sparrow). Other sensitive wildlife species include the Smooth
Greensnake, found in the mountains, spotted bat and Townsend’s big-eared bat.
Figure 10. Distribution of parcels (green) that intersect with critical wildlife habitat, with City
Council districts for reference.
Other wildlife species, although not recognized formally as sensitive, deserve attention in a street
lighting plan intended to reduce and avoid impacts. Fireflies are known to be sensitive to light
pollution and have popular appeal as wondrous symbols of the dusk and nighttime environment
(Lloyd 2006). The Natural History Museum of Utah is collecting firefly sightings from around
the state and has reports from both north and south of Salt Lake City and a few records have
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Bats are also significantly influenced by lighting conditions. Mexican free-tailed bats (Tadarida
brasiliensis) are well-known to residents because they roost at West High School near downtown
during migration. Other documented species include hoary bat (Lasiurus cinereus;
https://www.inaturalist.org/observations/3742269). It is likely that more species and locations
for bat foraging and roosting would be documented if acoustic surveys were conducted
(O’Farrell et al. 1999).
2.3 Effects of Lighting on Key Wildlife Groups
Artificial light at night can have a range of lethal and sub-lethal effects on wildlife (Longcore
and Rich 2004, Rich and Longcore 2006, Gaston et al. 2012, Gaston et al. 2013, Meyer and
Sullivan 2013). Some wildlife species will avoid areas with additional lighting (Beier 1995,
2006, Stone et al. 2009, Stone et al. 2012) or otherwise be adversely impacted (Hölker et al.
2010a, Hölker et al. 2010b, Longcore 2010, Gaston et al. 2013).
The formally recognized sensitive species in Salt Lake City, or at least potentially present,
include large and small mammals, migratory and resident birds, bats, one reptile, and at least one
plant species. The types of disruption from lighting that could occur for these groups include
attraction and disorientation leading to injury or death, disruption of connectivity between habitat
patches, interference with predator-prey relations and circadian rhythms that influence foraging
decisions, and disruption of pollination.
2.3.1 Attraction and Disorientation
Attraction/repulsion and disorientation are possible outcomes of encounters
between wildlife and artificial light at night (Longcore and Rich 2004).
The most well-known situation is the attraction and disorientation of
hatchling sea turtles on ocean beaches, which results in the death of the
juvenile turtles that do not reach the ocean (McFarlane 1963). The two
most relevant instances of attraction and disorientation for Salt Lake City
are the impacts on migratory birds and on insects.
Migratory Birds. Research with weather radar over the past five years has dramatically improved
understanding of the influence of city lights on migrating birds. Most songbird species migrate
at night and they can be detected and mapped on weather radar. A massive trove of radar data
has been accumulated over the past 25 years and so researchers can now use those data and
powerful new computing approaches to understand the influence of lights on the migratory paths
of birds.
Light at night escaping upwards so that it can be measured by a satellite is associated with
greater numbers of birds present during the day, especially in the fall when juveniles are
migrating south (La Sorte et al. 2017). As the birds are migrating southward they are attracted to
the lights of the city and then end up disproportionately using habitats in and around cities as
compared with potentially better habitats farther from cities (McLaren et al. 2018). Lights can
rapidly increase the density of migratory birds in an area at night. A study of the Tribute in Light
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light beams before they were turned on to 15,700 birds within 0.5 km 15 minutes after
illumination (Van Doren et al. 2017).
Attraction at night is only the first hazard. Urban habitats and especially business districts are
quite hazardous to these birds because once they are on the ground, they are susceptible to
collisions with glass, which they do not perceive as a barrier (Klem 1990, Sheppard and Phillips
2015). The combination of night-time lights followed by daytime glass exposure is a significant
threat to songbirds during the already strenuous migratory period (Cabrera-Cruz et al. 2018).
Radar data have been used to track the relative exposure of migratory birds to lights within U.S.
metropolitan areas ranked by area. The Salt Lake City–West Valley City urban area ranks 74th in
area among cities in the continental US by area. When evaluated for the number of migrating
birds based on radar tracking (average for 1995–2017) and the intensity to light as measured by
the VIIRS DNB satellite (average for 2012–2017), the city ranks 120th in exposure for the spring
and 112th in exposure for the fall (Horton et al. 2019) (Figure 11). Other cities have far more
migratory birds flying overhead per unit area. For example, New Orleans has many more birds
flying overhead because of its location on the Gulf Coast, where all of the birds heading to the
northern forests and back again to Central and South America funnel overhead.
Figure 11. Relative exposure of migrating birds to light in Salt Lake City within the 125 largest
metropolitan regions in the United States (Horton et al. 2019). Salt Lake City has relatively
fewer migratory bird species overhead during migration than other similarly sized metropolitan
regions.
Even though the relative exposure is low compared with other similar-sized cities, birds are
attracted to and die at the buildings of Salt Lake City. The city can take a leadership position by
reducing the amount of light escaping upward from lighting throughout the city and especially
downtown to reduce this unfortunate outcome.
Insects. Many families of insects are attracted to lights, including moths, lacewings, beetles,
bugs, caddisflies, crane flies, midges, hoverflies, wasps, and bush crickets (Sustek 1999, Kolligs
2000, Eisenbeis 2006, Frank 2006, Longcore et al. 2015a). Any lamp with significant emissions
120
100
80
60
40
20
0
Fall Exposure RankSalt Lake City
New Orleans
0 20 40 60 80 100 120
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in the ultraviolet or blue wavelengths is highly attractive to insects (Eisenbeis 2006, Frank 2006,
van Langevelde et al. 2011, Barghini and de Medeiros 2012). Insects attracted to lights are
subject to increased predation from a variety of predators, including bats, birds, skunks, toads,
and spiders (Blake et al. 1994, Frank 2006).
Moths are especially attracted to lights and they play a special role in the ecosystem as
pollinators. Moths are killed in collisions with the lights or by becoming trapped in housings
(Frank 1988, 2006). Short of death, this attraction removes native insects from their natural
environments (Meyer and Sullivan 2013) in what Eisenbeis (2006) calls the “vacuum cleaner
effect.” Attraction of insects by light results in significant reduction in pollination (Macgregor et
al. 2015, Macgregor et al. 2017) and this effect spills over into daytime insect communities
because of the decreased seed set and reproduction of plants (Knop et al. 2017).
Bats. The responses of different bat species to lighting are complex (Rydell 2006). Some faster-
flying and more maneuverable species will be attracted to lights, where they forage on insects
also attracted to the lights. Slower and less maneuverable species will avoid lights, essentially
being repulsed by their presence (Stone et al. 2009, Stone et al. 2012, Stone et al. 2015). Light at
the entrance of a roost can keep bats from emerging for their nightly foraging (Boldogh et al.
2007).
2.3.2 Loss of Connectivity
As is implied by the repulsion of some bat species by
nighttime lighting, the presence of permanent outdoor
lighting can severe landscape connectivity for wildlife
species (Stone et al. 2009). The existence of the lights
themselves, shielded or not, is sufficient to influence
wildlife movement (Beier 1995, 2006). This phenomenon
was illustrated by a radio telemetry study of young
mountain lions in Orange County, California (Beier 1995):
All travel in corridors and habitat peninsulas occurred at night. During overnight
monitoring, the disperser usually avoided artificial lights when in the corridor or
peninsula. For example, M12 [a juvenile mountain lion] consistently used dark areas as
he rapidly (<4 hr) traveled the grassy ridge (6.0 X 1.5 km) separating San Juan
Capistrano from San Clemente (Fig. 1). Also M12 seemed to use light cues when he
negotiated the tightest part of the Pechanga Corridor; his consistent movements in the
direction of the darkest horizon caused him to miss the only bridged undercrossing of I-
15.
Overnight monitoring showed that dispersers especially avoided night-lights in
conjunction with open terrain. On M12’s initial encounter with a well-lit sand factory and
adjacent sand pits, he took 2 hours and 4 attempts to select a route that skirted the facility,
after which he rested on a ridgetop for 2 hours. During 2 nights in the Arroyo Trabuco,
M8 explored several small side canyons lacking woody vegetation. He followed each
canyon to the ridgetop, where city lights were visible 300–800 m west. He stopped at
each canyon ridgetop for 15–60 minutes before returning to the arroyo, without moving
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Further data on the use of underpasses and the influence of lighting on landscape connectivity
have been reported. An experimental evaluation of underpass use by wildlife found that for mule
deer, even nearby lights affected movement compared with a reference period (Bliss-Ketchum et
al. 2016). Research conclusively shows that artificial night lighting can have an adverse impact
on the foraging behavior of bat species, and exclude certain species from foraging routes or areas
(Stone et al. 2009, Polak et al. 2011).
2.3.3 Foraging
Small mammals respond to illumination in their foraging
activities. For example, artificial light of 0.3 and 0.1 lux reduced
the activity, movement, or food consumption of a cross-section
of rodent species (Clarke 1983, Brillhart and Kaufman 1991,
Vasquez 1994, Falkenberg and Clarke 1998, Kramer and Birney
2001). This phenomenon also has been shown in natural (in
addition to laboratory) conditions (Kotler 1984a, Bliss-Ketchum et al. 2016, Wang and Shier
2017, Wang and Shier 2018).
The driving force behind patterns of activity and foraging by animals influenced by artificial
lights is presumably predation. Additional (artificial) light might increase success of visually
foraging predators, thereby increasing risk to their prey, with one critical exception: prey species
with a communal predator defence, such as schooling or flocking, have decreased risk of
predation with additional light. Evidence for this general pattern continues to accrue. Partridge
are documented to roost closer to each other on darker nights and can see predators farther away
on lighter nights (Tillmann 2009). Some species of bats avoid artificial lights to reduce predation
risk (Stone et al. 2009, Polak et al. 2011). A general review of nocturnal foraging suggests that
night is a refuge with decreased overall predation on birds and mammals, and that foraging
groups are larger at night, especially for clades that are not strictly nocturnal (Beauchamp 2007).
Songbirds that were experimentally relocated moved back to their home ranges at night, a result
that is most consistent with predator avoidance (Mukhin et al. 2009). Pollination is determined
by foraging activities and the distribution of insect foragers, which in turn are susceptible to
attraction, disorientation, and other behavioral disruptions from artificial lights (Knop et al.
2017).
Predator-prey systems are tightly tied into lunar cycles, with many relationships affected by lunar
phase (Williams 1936, Sutherland and Predavec 1999, Topping et al. 1999, Riou and Hamer
2008, Upham and Hafner 2013). Even within species, variation in color interacts with lunar
cycle to affect foraging success. White-morph Barn Owls have an advantage foraging during the
full moon because the light reflecting off their white feathers triggers their rodent prey to freeze
in place, while Barn Owls with darker colored feathers do not have this advantage (San-Jose et
al. 2019). Light pollution can be expected to interfere with such patterns (San-Jose et al. 2019).
Predator-prey relations probably also drive the influence of artificial lighting on bird nest
location. The one experimental study of the effect of streetlights on breeding bird density shows
a negative impact (De Molenaar et al. 2006). The streetlights in De Molnenaar et al.’s study
created a maximum illumination of 20 lux (1.8 footcandles). The adverse effects of these lights
(decreased density of Black-tailed Godwit nests) were experienced up to 300 m (984 ft) from APPENDIX D
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these lights, extending into areas with negligible increased illumination, which means that the
adverse impact results from the light being visible, rather than the amount of light incident on the
sensitive receptor.
2.3.4 Interference with Visual Communication
Artificial light at night affects species such as fireflies that communicate visually at night with
light. Although the distribution of fireflies is limited within the city, their recovery could be a
laudable urban conservation goal. Artificial light washes out the signals that fireflies use for
communication and is potentially contributing to the decline of fireflies and other organisms that
rely on bioluminescent communication (Lloyd 2006, Hagen and Viviani 2009, Viviani et al.
2010, Bird and Parker 2014). A Brazilian study documented lower species richness of fireflies
in areas of 0.2 lux and greater (even from sodium vapour lamps, which are otherwise considered
to be more wildlife friendly), except for those few species that naturally fly at greater
illumination (Hagen and Viviani 2009).
2.3.5 Physiological Responses
Birds. The research on the effects of ambient and artificial
lighting on bird reproduction goes back to the 1920s (Rawson
1923, Rowan 1938). Birds can be extremely sensitive to
illumination, and extension of foraging by species under artificial lights is documented in the
literature (Goertz et al. 1980, Sick and Teixeira 1981, Frey 1993, Rohweder and Baverstock
1996). Research shows an earlier start to seasonal breeding of birds in urban (lighted)
environments than rural (dark) environments (Havlin 1964, Lack 1965). Many of the
physiological impacts of lighting on birds are reviewed by De Molenaar et al. (2006) and
Longcore (2010).
• Dawn song in American Robins (Turdus migratorius) is influenced by ambient
illumination (Miller 2006);
• Dawn song and lay date in a songbird have been shown to be associated with proximity
to streetlights, with evidence that this affected mate choice, which has implications for
fitness (Kempenaers et al. 2010);
• Light of 0.3 lux can move reproductive seasonality of songbirds by a month and cause
irregular molt progression (Dominoni et al. 2013a, Dominoni et al. 2013b);
• Light is a major driver of the daily activity patterns of songbirds (study animal European
Blackbird; Turdus merula), causing them to be active earlier in the morning (Dominoni et
al. 2014);
• A songbird (Tree Sparrow; Passer montanus) exposed to 6 lux in the laboratory secreted
luteinizing hormone earlier than controls, and urban birds exposed to 3–5 lux exhibited
this pattern in the field; both of these response were statistically associated with night
lighting (Zhang et al. 2014);
• Artificial light outside of nest boxes affects perceived photoperiod of Great Tits (Parus
major), which the authors interpret as creating an ecological trap (Titulaer et al. 2012);
• Artificial light rather than traffic noise affects dawn and dusk song timing in common
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Artificial night lighting affects diurnal species substantially as well. As noted above, it affects
timing of dawn and dusk song, seasonality of reproduction, mate choices, and can extend
activities of diurnal species into the night (Stracey et al. 2014). Birds that sing earliest are
responding to increases in illumination so faint that they are undetectable by humans (Thomas et
al. 2002). This is true for impacts across species, where diurnal species are affected in numerous
ways by an altered nighttime environment (Miller 2006, Kempenaers et al. 2010, Titulaer et al.
2012, Dominoni et al. 2013a, Dominoni et al. 2013b, Da Silva et al. 2014, Dominoni et al. 2014,
Zhang et al. 2014, Da Silva et al. 2015).
Mammals. Similar impacts on both seasonality and daily rhythms are documented for mammals.
For example, lighting from a military base was shown to desynchronize the breeding time of
tammar wallabies in the field in Australia, as well as to suppress nightly melatonin production
(Robert et al. 2015). Studies on the physiological effects of light at night on mammals are
abundant, partly because of the implications for understanding human health (e.g., Zubidat et al.
2007, Zubidat et al. 2010). As a whole, they show that artificial light at levels far less intense
than previously assumed are able to entrain circadian rhythms and influence physiological
functions such as immune response (Bedrosian et al. 2011). For example, extremely dim light is
sufficient to entrain rhythms in mice, and can be done without phase shifting or reducing
production of melatonin (other physiological indicators of light influence) (Butler and Silver
2011). For shorter wavelengths (blue and green) entrainment takes place at 10–3 lux. Much
greater intensity, 0.4 lux, is needed for red light to entrain rhythms (Butler and Silver 2011).
This research is consistent with recently documented differences in mice behaviour for exposure
to 20 lux vs. 1 lux at night (Shuboni and Yan 2010). Mice that were exposed to dim (5 lux) light
at night consumed the same amount of food as those under dark controls, but gained weight as a
result of the shift in time of consumption (Fonken et al. 2010).
Plants. Plants “anticipate” the dawn with a synchronized circadian clock and increase immune
defence at the time of day when infection is most likely (Wang et al. 2011). The timing of
resistance (R)-gene mediated defences in Arabidopsis to downy mildew is tied to the circadian
system such that defences are greatest before dawn, when the mildew normally disperses its
spores (Wang et al. 2011). Preliminary experiments show that carbon assimilation is lower in
trees exposed to continuous night lighting, compared with controls in a “stereotypical urban
setting” (Skaf et al. 2010). Some plants might use light-triggered circadian rhythms to
synchronize expression of anti-herbivory compounds with periods of peak herbivory, leading to
increased loss from herbivory in out-of-phase plants (Goodspeed et al. 2012). The importance of
circadian rhythms in plants, for everything from disease response and flowering time to seed
germination, and the potential for disruption by night lighting, has not been explored widely
(Resco et al. 2009, Bennie et al. 2016).
Light at night also affects the perception of seasonal change by plants and their associated
physiological responses. Exposure to light at night is associated with earlier budburst in plants in
the United Kingdom, in a pattern that cannot be explained by the greater temperatures in cities
(ffrench-Constant et al. 2016). Trees exposed to nearby lights have long been observed to hold
on to their leaves later in the fall (Briggs 2006, Škvareninová et al. 2017, Massetti 2018) and
prevent seed set in plants cued to shorter daylengths (Palmer et al. 2017). APPENDIX D
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3 Consideration of Spectrum in Municipal Street Lighting Systems
The LED revolution in outdoor lighting has created new possibilities to select the spectral
composition of lights. Unlike lighting technology of the past, such as high-pressure sodium or
metal halide lamps, the range of colors that can be deployed using LEDs is wide. As a result, it
is possible to select spectral profiles that can either reduce or increase the effects of a street
lighting system on the visibility of stars in the night sky, on human circadian rhythms, and on
wildlife (Longcore 2018).
3.1 Effects on Wildlife
This review of the effects of lighting spectrum on wildlife is drawn from my recent article
(Longcore 2018), which can be consulted for additional details.
The effects of lights of different spectral composition on wildlife depends on the responses of
different wildlife groups to those lights. A limited number of “response curves” are available
that track the response for a species or group of species to light throughout the entire visible
spectrum (and into the portion of the spectrum invisible to humans). These curves have been
developed for insects in general, bees, moths, juvenile salmon, seabirds, and sea turtles. My
colleagues and I have developed methods to compare different lamp types for their effects across
these groups (Longcore et al. 2018a).
Some patterns are clear. Insect attraction to LEDs is lower across the board when compared with
lamps that emit ultraviolet light. Both “warm” and “cold” LEDs have been compared with metal
halide and mercury vapor lamps and found to attract less than a tenth of the number of insects, a
finding that is attributable to the difference in ultraviolet emissions (Eisenbeis and Eick 2011).
Conversely, most broad-spectrum LEDs used in outdoor lighting do have a potential to adversely
impact the perception of daylength (and thus seasonality) in plants, because the peak sensitivity
of the phytochromes that detect daylength are in range of LED peak emissions for most full-
spectrum LEDs.
Several approaches are available to summarize the quality of light from different sources. One is
to use the Correlated Color Temperature (CCT). This metric, although imperfect, is widely used
in lighting design. Some jurisdictions that regulating lighting to protect species have a hard cut-
off (e.g., no light allowed < 540 nm) or measure the amount of light emitted below certain
thresholds. Another possible metric is the degree to which a light interferes with the non-image
forming photoreceptors that result in disruption in circadian rhythms in humans, because nearly
all vertebrates will have a similar response curve for suppression of melatonin production at
night. Drawing on data from Longcore et al. (2018a), the response of different wildlife groups
against these possible metrics describing spectrum were plotted (Figure 12). Across all groups,
less blue light (shorter wavelengths) resulted in lower effects. As for metrics to describe this
pattern, correlation with CCT was strong, but melanopic lux (the brightness of the light as sensed
by melanopsin) correlated the best. These results will only hold true for lamps without
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Figure 12: Relationship of modeled effect of lamps on different wildlife species or groups
(juvenile salmon, Newell’s shearwater, sea turtles, insects, and their average) with percent
emissions <530 m, % emissions < 500 nm, correlated color temperature (CCT), and melanopic
power of the lamps. Data from (Longcore et al. 2018b).
CCT is not a perfect predictor of effects on wildlife, but it is a reasonable rule of thumb that
lower CCT will be less disruptive to wildlife and we already know that it will be less disruptive
for circadian rhythms and astronomical observation (Aubé et al. 2013). The lamps with the
lowest projected influence on wildlife overall were low pressure sodium (which is being phased
out), high pressure sodium, PC amber LEDs, and filtered LEDs (Figure 13). APPENDIX D
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Figure 13: Relationship of correlated color temperature to average wildlife sensitivity with
lamps and illuminants labelled. Data from (Longcore et al. 2018b).
These results represent the predicted effects of the lamps on wildlife. To account for preferences
in outdoor lighting, another ranking was created that incorporated a penalty for low color
rendering index (CRI). Any lamp with a CRI over 75 was assumed to have adequate color
rendering, while those with lower CRI were penalized in the overall index. The resulting ranking
of lamps is notable in that low pressure sodium ranks lower because of its extremely low CRI,
while PC Amber and filtered LEDs rank the highest, balancing both lower wildlife impacts with
reasonable if not high CRIs (Figure 14).
As a rule of thumb, CCT can be used as an indicator of wildlife effects, but this may not hold
true across all applications. Migrating birds cannot orient under red light and therefore solid red
lights are to be avoided on communication towers (Longcore et al. 2008). Green light has
support for minimizing attraction of nocturnal migrant birds (Poot et al. 2008). Many other
special cases exist and would require consultation with experts on a taxonomic group or species
at risk. For the species of concern in Salt Lake City, however, including insects as indicators of
riparian health, bats, and nesting birds, lower CCT will decrease ecological impacts when
combined with other good street lighting practices (low glare, no uplight, appropriate intensity,
and only lighting when warranted). APPENDIX D
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Figure 14: Ranking of lighting sources that equally weights wildlife response, melanopic
response, astronomical light pollution (Star Light Index (Aubé et al. 2013)), and Color
Rendering Index. Reprinted from (Longcore et al. 2018b). Shorter bars represent a combination
of lower wildlife responses and higher CRI.
None of the effects measured with these metrics addresses the scattering of light in the
atmosphere, but tools to evaluate the effects of different spectra on astronomical light pollution
are available to do that.
3.2 Effects on Dark Skies
The introduction and widespread adoption of 4000K and greater LED streetlights poses a
significant threat to astronomical observation and the quality of the night sky as a recreational
amenity. It is well-established that the preponderance of light at shorter wavelengths found in
high color temperature LEDs scatters more in the atmosphere and if replacing high-pressure
sodium lamps with similar intensity and shielding, will result in degradation of the night sky
(Kinzey et al. 2017). The effects of the adoption of high color temperature LEDs were quickly
noticed and documented by night sky advocates, who could see the degree to which full-
spectrum white lights adversely impacted the aesthetics of the night sky when compared with
lower color temperature high-pressure sodium systems (Figure 15). APPENDIX D
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Figure 15. View eastward from Antelope Island State Park, showing visible effect of spectrum on
night sky aesthetics. Photo from park’s application to become recognized as a Dark Sky Park by
the International Dark-Sky Association (2017).
Although the U.S. Department of Energy originally paid little attention to the adverse
environmental impacts of high-color temperature LEDs, focusing instead solely on energy
savings, it has recently returned to this question and issued a report (Kinzey et al. 2017)
investigating the role of lamp spectrum in degradation of the night sky, measured as sky glow.
Rather than focusing solely on spectrum, the report investigates the influence of associated
variables that are commonly adjusted in the process of converting from older lighting technology
to LEDs. For example, it is common for older lamps to have a drop lens below the lamp that
results in a portion of the light being reflected upward, above the horizontal plane from the lamp.
It has also become increasingly common for full-spectrum LEDs (e.g., at CCT 2700–4200 K) to
be reduced in measured intensity for daytime (photopic) vision when compared with the high-
pressure sodium lamp that the LED is replacing. Such reductions in intensity result from
complaints from residents that the new LEDs, although producing the same (photopic)
illumination (in lux) as the HPS, are perceived as far brighter because they intersect more with
the sensitivity of human dark-adapted (scotopic) vision. It is therefore often possible to reduce
the intensity of LEDs (measured in photopic lux) compared with HPS and still achieve equal or
greater visibility.
The study modeled the effects of different combinations of spectrum, uplight, and intensity under
different weather conditions, human vision adaptation levels, and distance from the lights. For
the purpose of illustration, the nearby viewer results are reproduced here (Figure 16). These
results compare high-pressure sodium as the baseline, with PC Amber LED (1872 K), and 2700–
6100 K LEDs. When compared on an equal basis for other factors (same uplight and intensity),
only the PC Amber produced roughly equivalent light pollution compared with HPS and all full-
spectrum LEDs produced significantly more light pollution, especially when considering human
night vision. When both HPS and LEDs were assumed to have 0% uplight and the LEDs were
set at half the intensity of the LEDs, then LEDs with CCT < 3000 K were comparable to or
produced less light pollution than HPS. Results were similar with HPS at 2% uplight and LEDs
at 0% uplight and 50% intensity.
The take-home message of this research for the Salt Lake City street lighting master plan is that
for LED lamps lights to reduce light pollution compared with the previously common HPS
lamps, they must be 0% uplight, 50% less bright, and with a CCT of no greater than 3000 K.
The minimum impact on light pollution could be achieved with PC Amber or comparable filtered
LEDs that produce a similar CCT as HPS (~ 1800 K). APPENDIX D
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Figure 16. Comparison of light pollution from different LED spectral power distributions (SPDs)
with light pollution from a high-pressure sodium light (horizontal dotted red line). SPDs (see
right): SPD5: 1872 K (PC Amber), SPD6 = 2704 K, SPD7 = 2981 K, SPD8 = 3940 K, SPD9 =
4101 K, SPD10 = 5197 K, SPD11 = 6101 K. APPENDIX D
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3.3 Human Circadian Rhythms
It is only in the last twenty years that the mechanism by which light affects human circadian
rhythms has been discovered (Berson et al. 2002). The human eye has non-image forming
retinal ganglion cells that detect light and perhaps contribute to perception of brightness but not
to discerning objects (Hattar et al. 2002). The pigment that detects the light is called melanopsin
and it differs in its sensitivity to light from the rods and cones that humans use for vision
(Brainard et al. 2001, Schmidt and Kofuji 2009). The peak sensitivity of melanopsin is around
480 nm, in the middle of the blue portion of the spectrum.
Evidence is strong that chronic exposure to light at night increases risk of cancer, diabetes,
obesity, and heart disease (Fonken and Nelson 2014, Bedrosian et al. 2016, Lunn et al. 2017).
The question for human circadian impacts from outdoor lighting is whether the exposures are
bright enough and whether time of exposure is sufficient to affect circadian rhythms.
Circadian rhythms can be affected by light in many pathways. The first pathway is suppression
of melatonin through exposure in the evening, especially after dusk. This exposure could be
indoors or outdoors, either in the sleeping habitat or not. Dose-response curves for light
exposure and melatonin suppression have been developed and it is the basis for the definition of
Circadian Light (Rea et al. 2010). The second pathway is through sleep disruption through
exposure to light in the sleeping habitat, even if the light levels are insufficient to suppress
melatonin. Lack of sleep and reduced long wave sleep, which is critical to recovery and repair
(Cho et al. 2016), can result from disturbance glare, as anyone ever awakened by moonlight can
attest.
It remains an open question whether indoor exposure to street lighting is of sufficient magnitude
to affect circadian rhythms directly, but recent research investigating light spectrum and cancer
risk suggests that the color of light outdoors in the vicinity of residences is an important risk
factor (Garcia-Saenz et al. 2018).
The influence of outdoor lighting on sleep has been investigated through epidemiological studies
that measure exposure using satellites, epidemiological studies using portable individual-level
measuring devices (comparing with satellite measures), and experimental studies in humans.
A set of studies from Haim, Kloog, Portnov, and colleagues provided correlational data
connecting satellite-measured light at night from the DMSP OLS system to breast and prostate
cancer, indicating a connection between outdoor lighting levels and rates of these cancers (Kloog
et al. 2008, Kloog et al. 2009a, Kloog et al. 2009b, Kloog et al. 2010, Kloog et al. 2011, Haim
and Portnov 2013). Similar studies have reinforced these findings in different populations
around the world (Bauer et al. 2013, Hurley et al. 2014, James et al. 2017).
Studies investigating sleep as the outcome also find an association with satellite-measured
outdoor lighting. For example, those in the higher exposure to light at night in South Korea as
measured by DMSP were 20% more likely to sleep less than 6 hours per night and on average
slept 30 minutes less than subjects in areas with lower outdoor lighting levels (Koo et al. 2016).
In a study in the United States, higher levels of outdoor lighting as measured by DMSP was
significantly associated with reporting < 6 hours of sleep per night, an effect that remained in APPENDIX D
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place even after accounting for noise and population density (Ohayon and Milesi 2016). In this
study, people who lived in the brightest areas were more likely to go to bed later, get up later,
and sleep less. They also were more likely to report that they were dissatisfied with sleep quality
or quantity and to be sleepy during the day. DMSP-measured light at night was negatively
associated with restorative long wave sleep. Importantly, this study validated that brightness in
bedrooms correlated positively with satellite-measured outdoor light (Ohayon and Milesi 2016).
Satellite-measured light at night was also associated with the use of more drugs for insomnia in a
second South Korean study (Min and Min 2018). Residents living in the lowest two quartiles of
light at night as measured by DMSP used significantly less insomnia medication, even after
accounting for age, sex, population density, income, body mass index, smoking status, alcohol
consumption, exercise, and psychiatric disease. Mean use of insomnia medication increased
with each quartile of light exposure from lowest to highest for each of three insomnia
medications (Min and Min 2018).
Most recently, a study of the NIH-AARP Diet and Health Study cohort in the United States
investigated sleep and exposure to light at night as measured by the DMSP satellite (Xiao et al.
2020). The highest levels of light exposure associated with 16% (women) and 25% (men)
increased probability of reporting short or very short sleep duration. Probability of reporting
short or very short sleep increased from lowest to highest quintiles of light at night in models that
adjusted for age, race, marital status, state of residency, smoking, alcohol, vigorous physical
activity, TV viewing, and median home value, population density and poverty rate at census tract
level (Xiao et al. 2020). The authors concluded that, “Taken together, these findings suggest that
the prevalence of sleep deficiency is higher in places with higher levels of LAN [Light at Night]”
(Xiao et al. 2020).
While studies using remotely sensed data detect associations between sleep disturbance,
circadian disruption, and associated diseases and light at night, others question the relationship
between outdoor lighting and indoor exposure to light at night. Leaving aside the point that
outdoor exposure to lighting can also contribute to circadian disruption, these studies focus on
relationships between indoor and outdoor exposure. Recent work confirms the relationship
between ground-level irradiance outdoors and satellite-based proxies for light at night. Using a
dataset or 515 ground-based measurements of illumination from the upper hemisphere, Simons
et al. (2020) showed that ground-based light exposure correlates highly with remotely-sensed
light (VIIRS DNB annual composite) and even more with the New World Atlas of Artificial
Night Sky Brightness (Falchi et al. 2016). This work conclusively establishes that satellite-
measured light at night is a proxy for ambient light in the environment on the ground at night, as
one would expect.
With this relationship now established (Simons et al. 2020), in retrospect the individual-level
studies of correlation between indoor light levels and satellite-measurements of light at night are
testing whether increased outdoor light levels correlate with higher indoor light levels and
documenting what those indoor levels might be. Along these lines, Rea et al. (2011) used a
Daysimeter device with a resolution of 0.1 lux and found that DMSP measurements had “no
apparent relationship” with personal-level exposure. The study concluded that outdoor lighting
could have little effect on circadian rhythms in their study population of teachers in upstate New
York, basing this conclusion on the assumption that measurable melatonin suppression would be APPENDIX D
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needed to cause sleep disruption. That is, they assume that light equivalent to a full moon
shining into a sleeping environment cannot affect sleep or circadian rhythms, which is a dubious
assumption. In a more recent Dutch study, individual-level light exposure for children was
measured indoors with a device that had a resolution of 0.1 lux (Huss et al. 2019). They found
an influence of outdoor light on indoor light during the darkest time period with a correlation of
0.31. It should be noted, however, that 94% of the children in the study had curtains that
controlled light entering the room. In a survey of lighting designers using their own light meters,
Miller and Kinzey (2018) reported measurements in a number of different contexts within
homes. At windows without drapes a maximum of 20 lux was reported, with a mean of 5 lux
and median of 0.5 lux. All of these dramatically elevated above natural conditions (a full moon
would produce 0.1–0.2 lux).
Experiments that involve exposures to light at night document illumination levels that affect
health and sleep outcomes. Sleeping under 5 lux of 5779 K light caused more frequent arousals,
more shallow sleep, and more REM sleep (at the expense of long wave deep sleep) (Cho et al.
2016). Light greater than 3 lux during the last hour of sleep was associated with weight gain in
an elderly population (Obayashi et al. 2016). In another study of an elderly population, increased
light at night and especially light at night > 5 lux was associated with 89% increased risk of
depression (Obayashi et al. 2013). Further studies indicate that elevated illumination is
associated with higher blood pressure as well, with associated excess deaths, at 3, 5, and 10 lux
exposures (Obayashi et al. 2014). Metrics of sleep quality (efficiency) were also consistently
lower with higher illumination at each category (3, 5, and 10 lux) (Obayashi et al. 2014).
Taken together, this research is consistent with a few different interpretations of the influence of
outdoor lighting on human circadian rhythms and health outcomes. It is possible that the
correlations between light at night and adverse health outcomes indicate instead variation in
another factor, such as air pollution, as suggested by Huss et al. (2019). The robustness of sleep
disruption correlations when controlling for population density, however, argues against that
interpretation (Ohayon and Milesi 2016). Xiao et al. consider this question and conclude: “[I]t
is also possible that the observed associations in our study population represent a true
relationship, but primarily driven by individuals whose ALAN exposure was more heavily
influenced by outdoor ALAN (e.g. individuals living in rooms facing bright streets and/or with
insufficient window treatments to block out light, or individuals with a high amount of nighttime
activities outside home).” Such an interpretation, that outdoor light can influence indoor
sleeping environments and associated sleep and health outcomes, is consistent with the literature
as it currently stands.
Accepting a plausible argument that outdoor lighting affects human sleep in at least some
contexts that depend on factors associated with socioeconomic status, the following areas of
concern follow for design of a street lighting system.
First, attention should be paid to minimize direct glare into windows of any habitable structure.
One cannot assume that people only sleep in bedrooms; residents challenged by housing costs
often use many rooms in apartments and houses for sleeping environments and the safest
assumption is that any room in a residence might be used for sleeping. The assumption should
also not be made that all residents have or can afford blackout shades or curtains. This becomes
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(Xiao et al. 2020), presumably because the same amount of light results in more impact because
of a lack of capacity to block light.
Second, circadian responses that result from melatonin suppression are heavily dependent on the
spectrum of light. As light is concentrated closer to the wavelengths of peak sensitivity for
melanopsin, the intensity of light (measured in lux) required to suppress melatonin decreases
(Grubisic et al. 2019). At 424 nm, the minimum illuminance for melatonin suppression is 0.1 lux
(Souman et al. 2018). The relative impact of different lighting sources can be predicted using the
melanopic response curve (Aubé et al. 2013, Longcore et al. 2018a). To illustrate this approach,
the melanopic power of lamp sources was standardized to compare with high pressure sodium
(HPS; Figure 17). All full-spectrum LED sources have a greater potential circadian impact than
HPS, including 2200 K (1.5 times HPS), 3200 K (2.5 times HPS), and 4300 K (3 times HPS).
Figure 17. Ranking of light sources by melanopic response (i.e. potential for circadian
disruption), compared with a typical High Pressure Sodium (HPS) lamp. Green colors have
equal or less melanopic response per lux, while purple colors have more melanopic response per
lux than HPS.
The sources that would have the lowest circadian impact are filtered LEDs that avoid the blue
portion of the spectrum almost entirely, or PC amber LEDs that do the same. Calculations have
not been done to compare LEDs at 50% intensity as has been done for astronomical light
pollution impacts. It is reasonable to assume that a similar result would be obtained, with a
reducing 50% in intensity for a ~3000K LED compared with HPS bringing it into parity with the
potential circadian disruption potential of HPS.
Anna's Light
LPS 18 W
AEL 75W
PC Amber Cree
74 WW CW10
74 WW CW7
150 W HPS
LLT Telescope Light
Kerosene Oil
Lumican 2251K
LSG Good Night 2016
CFL Greenlite 13 W
Iwasaki 60W
Philips AmbientLED
Cosmopolis 60W
Ceramic Metal Halide 70 W
3000K LED
A
OCTRON 32 W
Los Angeles LED
Yard Blaster
Full moon
LEDway Streetlight CW 54W
TL950
SORAA Vivid
D65
0% 100% 200% 300% 400% 500% 600%
Circadian Impact Relative to HPS APPENDIX D
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Third, planning for a healthy circadian environment should recognize high variation between
individuals in their sensitivity to light, including a 50-fold variation between people in melatonin
response to light exposure (Phillips et al. 2019). Children are more sensitive to disruption from
light at night than adults (Nagare et al. 2019). Office workers exposed only to dim light during
the day are more sensitive to disruption from light at night than those who work outside. Men
are more sensitive to light at night, including decreased “long sleep” with increased exposure
(Xiao et al. 2020). Some individuals are debilitated by the visual glare from LEDs that are not
properly directed and diffused (Ticleanu and Littlefair 2015).
A fair and equitable lighting design approach would recognize a need to accommodate the most
sensitive individuals in society in a manner that still allows lighting to achieve its goal of
providing a safe environment for pedestrians, cyclists, and people in vehicles. Because some of
the medical conditions that are exacerbated by glare may be considered disabilities, it
furthermore might be a prudent risk management step to explicitly incorporate these concerns in
design to ensure compliance with the Americans with Disabilities Act. Published studies thus far
have not shown a decrease in traffic accidents associated with conversion to full-spectrum white
LEDs (e.g., >2700 K) (Marchant et al. 2020). Total pedestrian and cyclist deaths in Los Angeles
have increased since conversion from HPS to 3000–4300 K LEDs in 2009.1 Whatever marginal
benefits might be associated with higher CCT street lighting, they have not been sufficient to
result in significant decreases in accidents that have been documented in published studies.
Although a full cost-benefit analysis is beyond the scope of this report and should be the subject
of future research, a prudent approach to balance these human health and safety issues is to: use
the lowest CCT deemed acceptable, specify high-quality optics to ensure delivery of light on
desired surfaces instead of as glare, and avoid light trespass onto windows of any residential
property.
1 See https://la.streetsblog.org/2019/10/29/vision-non-zero-the-human-and-financial-toll-of-los-angeles-dangerous-
roads/ APPENDIX D
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4 Design Strategies for a Healthy Nocturnal Infrastructure
With the adoption of a Street Lighting Master Plan, an opportunity arises to reduce unwanted
outcomes from outdoor lighting that might include degradation of the experience of the night sky
in the region, disruption of human circadian rhythms, and interference with behavior of sensitive
wildlife species within the city. Strategies are available to reduce these impacts, some of which
can be implemented at all locations where street lighting is warranted, and others that could be
applied in zones with sensitive resources or known adverse impacts.
4.1 Systemwide Approaches
Reducing the adverse effects of artificial light at night is a matter of ensuring that the light is
away enough for the identified need, but not more.
4.1.1 Need-based Lighting
In defining the terms under which street lighting is warranted, consideration should be given in
all instances to the threshold for need to ensure that the installation is supported by verifiable
benefits. The need for lighting at night is in part a subjective judgment based on human feelings,
so equal consideration should be given to those who are more comfortable with less light as to
those who desire more light and final determinations made through a transparent and fair process
that evaluates the costs and benefits.
4.1.2 Shielding and Directionality
For all of the reasons discussed in this report, lights should be directed toward their intended
targets (mostly roads and sidewalks) and not upwards or into other locations where sensitive
receptors might be present (e.g., bedroom windows, habitats). This consideration will usually be
built into a modern street lighting plan through specification of luminaire performance in terms
of backlight, uplight, and glare. Uplight should be assiduously avoided throughout the system.
This step alone will significantly reduce the current contribution of Salt Lake City to light
pollution in the region as viewed from the surrounding open spaces and natural lands.
4.1.3 Intensity, Dimming, and Controls
Any time a natural environment is experiencing illumination greater than the full moon (>0.1
lux), or even greater than a quarter moon (0.01 lux), one can assume that species are being
affected. This is the case because many species show lunar cycles in behavior, often driven by
predator–prey relationships that can be interrupted by elevated illumination (Price et al. 1984,
Daly et al. 1992, Upham and Hafner 2013). For example, light as dim as 0.01 lux can inhibit
foraging by small rodent species (Kotler 1984b).
Strategies that could be deployed around light intensity across the street lighting system include
setting the maximum intensity of lights lower, dimming or extinguishing lights according to a
pre-set schedule, and use of programmable and flexible controls to adjust intensity in response to
need. APPENDIX D
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1. If full-spectrum LEDs are to be used (e.g., 2700K, 3000K), then the intensity must be at
least half of that measured (in lux) for high pressure sodium to avoid increased light
pollution impacts. Lower color temperature LEDs (e.g., 1800K, 2000K, 2200K) would
require testing to set the maximum operational intensity to achieve system objectives.
2. Regularly programmed dimming or shut-off is a possibility for the system. Part-night
lighting, where lights are shut off after a curfew is an improvement over whole-night
lighting for bats but not adequate to reduce all impacts (Azam et al. 2015, Day et al.
2015). For the whole system in Salt Lake City, a dimming schedule, especially for
residential areas, that reduced output from (for example) midnight to 5 a.m. seems
feasible and would reduce overall contribution to regional light pollution, reduce human
circadian disruption, and save energy.
3. Controls can be used as a complement to a lower overall intensity setting. When
additional illumination is needed, in coordination with City officials, lighting levels can
be increased during the period of the need and then reduce to the “normal” level.
Controls can also be used on a neighborhood by neighborhood basis to find the
illumination level that is most consistent with and useful within the character of the
neighborhood.
4.1.4 Spectrum
The unwanted impacts of the street lighting system would be minimized by using the lowest
possible CCT for the most lights in the system. For wildlife, human health, and preserving dark
skies, the preferable choice would be lamps with CCT <2000K. Other considerations lead to the
use of higher color temperatures in some zones, but the lower the color temperature can be kept
on average, the greater the environmental benefit.
Low CCT lights are commercially available. For example, Signify makes 1800K cobra-head
street lights (StreetView, RoadView, EcoForm, RoadStar) and decorative models as well
(Domus, MetroScape, UrbanScape, LytePro). Cyclone produces a 1800K street light, as does
Ignia Light (Figure 18). SNOC provides a 2200K light that mixes white and amber diodes, as
does Ignia Light (Figure 19). Lumican also sells a range of street light luminaires that include
1700K through 2200K. RAB lighting sells a 2000K luminaire (Triboro) to match the color of
HPS (https://www.rablighting.com/feature/led-roadway-lighting-triboro; Figure 20). Siteco sells
1750K, 1900K and 2200K street lights. CWES builds luminaire systems that use a warm white
LED and a filter to avoid blue light emissions while keeping lumens per Watt high in comparison
with 2700K and 3000K LEDs (Figure 21). Some communities in Utah are even manufacturing
their own filters to protect the night sky and the tourism industry associated with it (Figure 22).
Where full-spectrum light is desired for aesthetic reasons or other considerations, it should in no
instance exceed 3000K and preferably not 2700K. Lower CCTs should be considered for
residential neighborhoods citywide as acceptable to City officials and residents. APPENDIX D
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Figure 18. Application of PC Amber lights by Ignia Light.
Figure 19. Demonstration of mix of white and amber diodes to produce 2200K light for a
roadway application by Ignia Light.
Figure 20. RAB application of 2000K light to match color of High Pressure Sodium lamps. APPENDIX D
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Figure 21. C+W Energy Solutions provides filtered LEDs that use with a warm white LED and
filter blue light, resulting in a greenish yellow color that contrasts with yellow light of stop
lights.
Figure 22. Ivins, Utah is using filtered LEDs to protect the night sky
(https://www.kuer.org/post/fast-growing-southwest-utah-one-city-organizes-protect-night-
sky#stream/).
4.2 Ecological Overlay Strategies
In addition to systemwide strategies, which would be implemented throughout all instances of
land uses and road segment conditions (e.g., roadway type and associated land use
combinations), several ecological overlay strategies would be appropriate that recognize the
sensitive natural resources of Salt Lake City. These strategies are tailored to geographic regions
where modifications to the light specifications could be used to reduce unwanted environmental
impacts. APPENDIX D
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Each of these strategies is based on a geographic footprint. Spatial data to delineate these
regions were either obtained from custodians of those data or digitized by hand based on aerial
photograph interpretation. These data sources include:
• Important Bird Areas (from National Audubon Society spatial data webserver);
• Bird Collision Survey Zone (digitized from map provided by Tracy Aviary);
• Parcels that intersect with Critical Wildlife Habitat (digitized from Salt Lake City open
space acquisition plan);
• Jordan River Habitat Zone (digitized from aerial photograph interpretation of natural
habitat);
• Urban Creek Zone (digitized from aerial photograph interpretation of natural habitat);
and
• Community Parks and Neighborhood Parks (from Salt Lake City spatial data webserver).
The digitized habitat zones could be revised with field checks. The purpose of these layers is
only to classify roadway lengths for lighting strategies and should not be interpreted as a precise
mapping of habitat values.
Figure 23. Zones considered for ecological lighting strategies.
A set of additional guidance to reduce impacts that are targeted to the resources in each of these
zones is proposed (Table 1). APPENDIX D
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Table 1. Strategy matrix for ecological overlay zones and major land uses.
Strategy Uplight Spectrum
(CCT K)
Dimming Part-night
lighting
Intensity
(of HPS
lumens)
Commercial /
Bird collision
zone
0.02 ≤3000 During
migration
No 50%
Critical Wildlife
Habitat
0 ≤2200K No No 50%
Community Parks
Natural Lands
0 ≤2200K No Yes 50%
Jordan River 0 ≤1900K No Yes 50%
Urban Creeks 0 ≤1900K No Yes 50%
4.2.1 Bird Collision Zone
The area which is currently monitored for bird collisions is found in the central business district.
It is also the brightest location when observing the region from space. Mortality of birds results
from the mixture of lights that attract nocturnally migrating birds with the presence of tall
buildings with large expanses of glass with which bird collide. The lights draw the birds in and
then the glass kills them (Sheppard and Phillips 2015). Current lighting in this zone includes
many decorative lights that are not yet shielded to direct light downward. The high lighting
levels provided in a commercial zone with the lack of shielding explains the brightness of this
area from above at night. Recognizing the need for lighting appropriate for a commercial
business district and its level of activities leads to a suggestion of compromise for lighting.
Rather than proposing no uplight, even reducing uplight to 2% would represent a dramatic
improvement over existing conditions. If no uplight is possible, it would be preferable. Color
temperature in this area, and other commercial zones, should be capped at 3000 K. Intensity of
lights should be set to 50% of that measured for previous high-pressure sodium lamps to account
for human sensitivity to 3000 K lights. With full controls available for the system, a dimming
program could be further implemented during peak migration periods (April/May and
September/October). If only one period is chosen, it should be fall because the fall migration
includes all of the young of the year, which are especially susceptible to collision. Such
additional dimming could be implemented either all night or after midnight or another set time.
For this area, actions on the part of the City might catalyze participation in mitigation approaches
by property managers (Light Out Salt Lake organized by the Tracy Aviary); turning lights out
inside buildings at night would further reduce attraction of birds and resulting mortality.
4.2.2 Critical Wildlife Habitat Zone
The region that intersects with parcels containing critical wildlife habitat is found in the foothills
to the east of downtown and then in the flat shorelands to the west. The western area also
includes the two globally significant Important Bird Areas. Because this zone contains a range
of land uses, including commercial, industrial, and residential areas, the proposal is to match the
low color temperature of previous lighting systems (e.g., 2000–2200 K) with full cut-off lighting APPENDIX D
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to reduce impacts on nearby sensitive resources. This lower temperature is especially important
near the Great Salt Lake, which is a source of fog (Hill 1988). Fog is extremely efficient at
reflecting light and recent research has shown that foggy conditions result in a 6-fold increase in
night sky brightness (a measure of light pollution) (Ściężor et al. 2012). Fog also scatters light
down into habitats. Full cut-off lighting at a low enough color temperature to allow reasonable
color rendering should balance the needs of the land uses in these zones with the sensitive
resources found there.
4.2.3 Jordan River and Urban Creeks
The Jordan River and the urban creeks cut through the street grid such that they intersect with
only a few street lights along any given segment. It might therefore be possible to minimize
impacts to these riparian zones by using low color temperature lights as street segment intersect
these zones. Two major considerations in riparian zones are insect attraction and bat impacts,
since both groups will be found at higher density in these zones. Best practices for reducing
impacts to bats (Voigt et al. 2018) include a limit on light at the edge of habitat of 0.1 lux,
avoiding direct glare into habitats, and seeking to avoid light <540 nm. A low CCT light would
minimize insect attraction (Longcore et al. 2018a). Red lights are being used in Europe to
minimize impacts to bats (Spoelstra et al. 2017) but it is not clear if red light would be acceptable
within this context.
4.2.4 Community Parks and Natural Lands
Community parks and natural lands may contain sensitive species and often have areas that are
closed after dark. Lighting surrounding them could be limited in CCT to 2200 K and lights on
roads within parks might be shut off after a curfew. Darkness in these instances can serve to
reduce unwanted activity because any lights brought into a dark park would indicate unallowable
activity. Recommendations for community parks and natural lands will probably need to be
tailored by site to accommodate variations in use, park type, and surrounding land uses. Tracy
Aviary is located in a community park and has captive birds that are kept outdoors. Reducing or
eliminating street lighting around any outdoor exclosures with captive birds is recommended for
the health of the birds. APPENDIX E
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APPENDIX E
SALT LAKE CITY, UT
Street Lighting Master Plan
VOLUME 2 - TECHNICAL GUIDANCE AND IMPLEMENTATION
JUNE 2020
3
LIGHTING DESIGN PROCESSHOW TO USE THIS GUIDE ..........................................1
LUMINAIRE SUBMITTAL FORMS .................................3
PROCESS FOR EVALUATING THE LIGHTED
ENVIRONMENT .........................................................3
Determine Lighting Strategy based on Site
Location .......................................................................3
Establish Lighting Warrants ..............................3
Determine Street Classifications .....................5
Determine Adjacent Land Use .........................5
Determine Pedestrian Activity Levels ...........7
COMPREHENSIVE IMPROVEMENTS ...........................8
Purpose ........................................................................8
Lighting Design Process ......................................8
Lighting Applications ............................................8
MINIMAL IMPROVEMENTS ......................................51
Confirm Existing Conditions .............................51
Supplemental Improvements ...........................51
One-For-One Replacement ..............................51
LIGHTING CONTROLS AND ADAPTIVE DIMMING
STRATEGIES ............................................................51
LIGHTING CALCULATIONS ......................................54
Purpose .....................................................................54
How To Set Up A Calculation .........................54
TABLE OF CONTENTS
4
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
THIS PAGE LEFT INTENTIONALLY BLANK
5
LIGHTING DESIGN PROCESSHOW TO USE THIS DESIGN GUIDE
This section outlines the street lighting design
process and the steps to developing quality
street and pedestrian lighting. The criteria used
is from the Illuminating Engineering Society
of North America’s (IES) American National
Standard Practice for Roadway Lighting (RP-
8-18).
Lighting designers should evaluate each
lighting installation on a block by block basis
and use the criteria to identify the appropriate
lighting strategy based on the information
provided in the following sections.
LUMINAIRE SUBMITTAL FORMS
Designers and engineers will use street and
pedestrian luminaire submittal forms found in
Appendix E to ensure that all luminaire criteria,
set forth in this chapter as well as in the Luminaire
Criteria Tables, are met. These forms should be
completed during the lighting design process
and most of the information on the forms can
be found in the luminaire specification sheet.
These forms will aid the City in approving
luminaire selection for construction.
PROCESS FOR EVALUATING THE LIGHTED
ENVIRONMENT
DETERMINE LIGHTING STRATEGY
BASED ON SITE LOCATION
The majority of lighting installations in Salt
Lake City are street and/or pedestrian lights for
which the City has adopted a standard. Using
the same equipment for most installations
reduces inventory and makes replacements
and repairs more efficient and cost effective.
However, this master plan and existing lighting
programs allow for areas within the city to
differentiate themselves with unique lighting
features. When designing street and pedestrian
lighting, the designer must be aware of the
area and if there are any unique influences. All
new lighting in a character area should match
and comply with luminaire style and criteria
established in this Master Plan. Some character
districts in the City, such as residential areas,
may require lighting redesign, regardless of
existing conditions to meet applicable criteria.
Areas not included in a character district will
be lighted with cobrahead style luminaires
and standard pedestrian scale luminaires that
meet the criteria and spacing based on road
classification established in the Master Plan.
ESTABLISH LIGHTING WARRANTS
The Lighting Warrants Table below considers all
factors and leads the designer to the appropriate
lighting strategy based on street classification,
adjacent land use, and pedestrian conflict. The
next sections provide the user with background
and guidance on the Lighting Warrants Chart
to identify appropriate attributes and select
the appropriate lighting strategy. The designer
must use the appropriate strategy and include
any character influences in their design. Not
all streets in the City will warrant continuous
lighting, but all streets with continuous lighting
must meet the lighting criteria set forth by IES
RP-8-18.
LIGHTING DESIGN PROCESS
6
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
TABLE 1: LIGHTING WARRANTS - ARTERIAL
ARTERIAL STREET
PED EXISTING CONDITIONS STREET
LIGHTING PED LIGHTING PG. #
COMMERCIAL
HIGH Sidewalk Lit By Streetlight Continuous Optional Non-cont.25, 31
Sidewalk NOT Lit by Streetlight Continuous &Continuous 29
MED Sidewalk Lit By Streetlight Continuous Optional Non-cont.25
Sidewalk NOT Lit by Streetlight Continuous &Non-cont.31
LOW Sidewalk Lit By Streetlight Non-Cont. NA 27
Sidewalk NOT Lit by Streetlight Non-cont. NA 27
OFFICE PARK LOW Sidewalk Lit By Streetlight Non-Cont. NA 27
Sidewalk NOT Lit by Streetlight Non-cont. NA 27
DOWNTOWN
HIGH
Cactus Poles Continuous Cactus Pole Lighting 19
Sidewalk Lit By Streetlight Continuous Optional Non-cont.25, 31
Sidewalk NOT Lit by Streetlight Continuous &Continuous 29
MED
Cactus Poles Continuous Cactus Pole Lighting 19
Sidewalk Lit By Streetlight Continuous Optional Non-cont.25
Sidewalk NOT Lit by Streetlight Continuous &Non-cont.31
INDUSTRIAL LOW Sidewalk Lit By Streetlight Int. Only NA 33
Sidewalk NOT Lit by Streetlight Int. Only NA 33
MULTIFAMILY
RESIDENTIAL MED Sidewalk Lit By Streetlight Continuous Optional Non-cont.25, 31
Sidewalk NOT Lit by Streetlight Continuous &Non-cont.31
SINGLE FAMILY
RESIDENTIAL LOW Sidewalk Lit By Streetlight Continuous Optional Non-cont.25, 31
Sidewalk NOT Lit by Streetlight Continuous Optional Non-cont.25, 31
OPEN SPACE
MED Sidewalk Lit By Streetlight Non-Cont. NA 27
Sidewalk NOT Lit by Streetlight Non-cont. NA 27
LOW Sidewalk Lit By Streetlight Int. Only NA 33
Sidewalk NOT Lit by Streetlight Int. Only NA 33
* High pedestrian conflict is only found in Downtown, Sugarhouse, Trolley Square, and within one
block of the University of Utah and Smith’s Ballpark
7
LIGHTING DESIGN PROCESSTABLE 2: LIGHTING WARRANTS – COLLECTOR
* High pedestrian conflict is only found in Downtown, Sugarhouse, Trolley Square, and within one
block of the University of Utah and Smith’s Ballpark
COLLECTOR
PED EXISTING CONDITIONS STREET
LIGHTING PED LIGHTING PG. #
COMMERCIAL
HIGH Sidewalk Lit By Streetlight Continuous OR Continuous 34
Sidewalk NOT Lit by Streetlight Continuous &Continuous 38
MED Sidewalk Lit By Streetlight Continuous OR Continuous 34
Sidewalk NOT Lit by Streetlight Continuous &Non-cont.40
LOW Sidewalk Lit By Streetlight Non-cont. NA 36
Sidewalk NOT Lit by Streetlight Non-Cont. NA 36
OFFICE PARK LOW Sidewalk Lit By Streetlight Non-cont. NA 36
Sidewalk NOT Lit by Streetlight Non-cont. NA 36
DOWNTOWN
HIGH
Cactus Poles Continuous Cactus Pole Lighting 19
Sidewalk Lit By Streetlight Continuous OR Continuous 34
Sidewalk NOT Lit by Streetlight Continuous &Continuous 38
MED
Cactus Poles Continuous Cactus Pole Lighting 19
Sidewalk Lit By Streetlight Continuous OR Continuous 34
Sidewalk NOT Lit by Streetlight Continuous &Non-Cont.40
INDUSTRIAL LOW Sidewalk Lit By Streetlight Int. Only NA 44
Sidewalk NOT Lit by Streetlight Int. Only NA 44
MULTIFAMILY
RESIDENTIAL MED Sidewalk Lit By Streetlight Continuous Optional Non-cont.42
Sidewalk NOT Lit by Streetlight Continuous &Non-cont.40
SINGLE FAMILY
RESIDENTIAL LOW Sidewalk Lit By Streetlight Non-Cont.OR Non-cont.36,42
Sidewalk NOT Lit by Streetlight Int. Only &Non-cont.44,42
OPEN SPACE
MED N/A
LOW Sidewalk Lit By Streetlight Int. Only NA 44
Sidewalk NOT Lit by Streetlight Int. Only NA 44
8
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
TABLE 3: LIGHTING WARRANTS – LOCAL
* High pedestrian conflict is only found in Downtown, Sugarhouse, Trolley Square, and within one
block of the University of Utah and Smith’s Ballpark
LOCAL
PED EXISTING CONDITIONS STREET
LIGHTING PED LIGHTING PG. #
COMMERCIAL
HIGH Sidewalk Lit By Streetlight Continuous OR Continuous 45,50
Sidewalk NOT Lit by Streetlight Non-cont.&Continuous 48
MED Sidewalk Lit By Streetlight Non-Cont. OR Continuous 47, 50
Sidewalk NOT Lit by Streetlight Non-cont.OR Continuous 47, 50
LOW Sidewalk Lit By Streetlight Int. Only OR Non-cont.36
Sidewalk NOT Lit by Streetlight Int. Only OR Non-cont.36
OFFICE PARK LOW Sidewalk Lit By Streetlight Int. Only OR Non-cont.53, 52
Sidewalk NOT Lit by Streetlight Int. Only OR Non-cont.53, 52
DOWNTOWN
HIGH
Cactus Poles Continuous Cactus Pole Lighting 19
Sidewalk Lit By Streetlight Continuous OR Continuous 45,50
Sidewalk NOT Lit by Streetlight Non-cont.&Continuous 48
MED
Cactus Poles Continuous Cactus Pole Lighting 19
Sidewalk Lit By Streetlight Non-Cont. OR Continuous 47, 50
Sidewalk NOT Lit by Streetlight Non-Cont.OR Continuous 47, 50
INDUSTRIAL LOW Sidewalk Lit By Streetlight Int. Only NA 53
Sidewalk NOT Lit by Streetlight Int. Only NA 53
MULTIFAMILY
RESIDENTIAL MED Sidewalk Lit By Streetlight Int. Only &Continuous 53
Sidewalk NOT Lit by Streetlight Int. Only &Continuous 53
SINGLE FAMILY
RESIDENTIAL LOW Sidewalk Lit By Streetlight Int. Only Optional Non-Cont.53, 52
Sidewalk NOT Lit by Streetlight Int. Only Optional Non-cont.53, 52
OPEN SPACE
MED N/A
LOW Sidewalk Lit By Streetlight Int. Only NA 53
Sidewalk NOT Lit by Streetlight Int. Only NA 53
9
LIGHTING DESIGN PROCESSStreet classification is used to determine the
lighting warrants for a street, along with the
surrounding environment and pedestrian conflict.
Figure 1 shows all street classifications throughout
the city. The following street and roadway
definitions are from IES RP-8-18.
FREEWAY:
A divided highway with full control of access.
Oftentimes with great visual complexity and high
traffic volumes. This roadway is usually found in
major metropolitan areas in or near the central
core and will operate at or near design capacity
through some of the early morning or late evening
hours of darkness.
*Freeway, which are UDOT facilities, are not
included in the scope of this Masterplan.
MAJOR (ARTERIAL):
That part of the roadway system that serves as
the principle network for through-traffic flow.
The routes connect areas of principle traffic
generation and important rural roadways entering
and leaving the city. These routes are often known
as “arterials”. They are sometimes subdivided
into primary and secondary; however, such
distinctions are not necessary in roadway lighting.
These routes primarily serve through traffic and
secondarily provide access to abutting property.
COLLECTOR:
Roadways servicing traffic between major and
local streets. These are streets used mainly for
traffic movements within residential, commercial,
and industrial areas. They do not handle long,
through trips. Collector streets may be used for
truck or bus movements and give direct service
for abutting properties.
LOCAL:
Local streets are used primarily for direct access
to residential, commercial, industrial, or other
abutting property. They make up a sizable
percentage of the total street system but carry a
small proportion of vehicular traffic.
INTERSECTIONS:
A traffic conflict area in which two or more streets
join or cross at the same grade. The outside edge
of pedestrian crosswalks defines intersection
limits. If there are no pedestrian crosswalks, the
stop bars define the intersection. If there are
no stop bars, the intersection is defined by the
radius return of each intersection leg. Intersection
limits may also include the area encompassing
channelized areas in which traffic is directed into
definite paths by islands with raised curbing.
DETERMINE STREET CLASSIFICATIONS
0 1.5 30.75
Miles
STREET CLASSIFICATIONS KEY
LOCAL
ARTERIAL
COLLECTOR
FREEWAY
I-80
I-80
I-215I-215
I-15
HWY
154
400 S.
S. TEMPLE
FOOTHILL700 E.1700 S.1700 W.Figure 1: Street Classifications Map
10
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
Adjacent land use is a key factor in determining
lighting strategy as it directly correlates to the
number of pedestrians and vehicles in the area
during nighttime hours. Areas of increased
traffic volume at night warrant additional
lighting, whereas areas that typically do not
have much traffic after dark warrant base level
lighting. Figure 2 is the Land Use Map. Adjacent
land use should be evaluated according to the
consolidated zoning provided in this master
plan. For projects that are on the boundaries
between land uses, the designer should select
the lower criteria with more stringent light
trespass to protect residential and open space
uses. If the project includes areas that are
within, or adjacent to, a Critical Wildlife Area,
all luminaire installed should meet the luminaire
requirements of the protected area.
COMMERCIAL
Commercial land use is a diverse classification
encompassing high, medium and low pedestrian
and traffic volumes. Areas with concentrated
restaurant and retail establishments, such as
the Sugarhouse Business District and 9th &
9th, typically see medium to high pedestrian
and traffic volumes during nighttime hours and
should have increased light levels and possibly
additional pedestrian lighting. However, big
box stores and strip malls do not typically
see the same number of pedestrians during
nighttime hours and can have reduced light
levels. Designers must carefully evaluate the
pedestrian and traffic volume where lighting
improvements are being made and select
the proper lighting criteria to create a safe
and comfortable nighttime environment for
pedestrians and vehicles.
OFFICE PARK
Office Parks are defined as areas where people
tend to work during the day but are mostly
vacant during nighttime hours. Establishments
in this classification are generally open between
8:00 A.M. and 6:00 P.M. but typically close in
the early evening and are not open into the
night.
DOWNTOWN
Downtown Salt Lake City is the heart of the
retail and restaurant business in the valley and
attracts people at all times of the day. This area
typically sees high and medium pedestrian and
traffic volumes and is lighted by the historic
Cactus Poles. Lighting in Downtown should
focus on pedestrian safety and properly
illuminating crosswalks and sidewalks. In most
cases luminaire spacing has already been
established so it is essential that designers
select the proper distribution and lumen output
INDUSTRIAL
Industrial land use is defined by manufacturing
and distribution within the City. This land use
includes, but is not limited to, the establishments
found south of the airport off of California Ave.
Industrial land use has very minimal pedestrian
usage, especially during nighttime hours and
requires minimal lighting. Additionally, most of
the industrial land use areas within Salt Lake
City are also within Critical Wildlife Habitats
and will require appropriate lighting to minimize
environmental impacts.
MULTIFAMILY RESIDENTIAL
DETERMINE ADJACENT LAND USE
11
LIGHTING DESIGN PROCESSMultifamily residential is characterized by multiple
separate housing units for residential inhabitants
are contained within on building or several
buildings within one complex. When designing
lighting on streets adjacent to multifamily
residential areas a medium pedestrian conflict
should be used as there are typically higher
pedestrian and vehicle volumes. Residential areas
are typically on streets with lower speed limits
and less traffic, however this is not always the
case. Salt Lake City has residential land use on all
street classifications, arterial, collector and local
creating multiple lighting strategies that may be
appropriate. Designers should consider the safety
of pedestrian and vehicles when selecting the
appropriate lighting strategy while respecting the
residents by minimizing light trespass.
SINGLE FAMILY RESIDENTIAL
Single family residential is characterized by a
stand-alone dwelling serving as the primary
residence for one family. Single family residential
areas typically have less pedestrian volume, and
when designing lighting in these areas, a low
pedestrian conflict should be used. Residential
areas are typically on streets with lower speed
limits and less traffic, however this is not always
the case. Salt Lake City has residential land use
on all street classifications, arterial, collector and
local, creating multiple lighting strategies that may
be appropriate. Designers should consider the
safety of pedestrian and vehicles when selecting
the appropriate lighting strategy while respecting
the residents by minimizing light trespass.
OPEN SPACE
The purpose of the OS Open Space District
is to preserve and enhance public and private
open space, natural areas, and improved park
and recreational areas. These areas provide
opportunities for active and passive outdoor
recreation, provide contrasts to the built
environment, preserve scenic qualities, and
protect sensitive or fragile environmental areas.
Examples of Open Space within the City include
City Creek Canyon, Salt Lake City Cemetery, and
along the Jordan River. Any Streets bordering
the foothills are considered to be along Open
Space as well. These streets typically see minimal
pedestrian usage and are within Critical Habitat
areas requiring additional measures to ensure
environmentally friendly street lights are used.
¯0 1 20.5 Miles
Zones
Low Density Residential
Multi Family Residential
Industrial
Commercial
Downtown
Office Park
Agriculture
Institutional
Airport
Transit Service Areas
Parks
Open Space
Public Land/Civic
Figure 2: Adjacent Land Use Map
12
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
IES pedestrian volumes represent the total
number of pedestrians walking in both
directions on a typical block or 660 foot
section. Pedestrian counts and traffic studies
take precedence over other references.
The following are pedestrian classification
definitions per IES RP-8-18. The pedestrian
counts should be taken during darkness hours
when the typical peak number of pedestrians
are present. This typically occurs during early
morning hours if a school or similar destinations
are nearby. The lighting designer should
determine what the typical peak hours are for
each street.
HIGH:
Areas with significant numbers (over 100
pedestrians an hour) of pedestrians expected
to be on the sidewalks or crossing the streets
during darkness. Examples are downtown retail
areas, near theaters, concert halls, stadiums,
and transit terminals.
MEDIUM:
Areas where fewer (10 to 100 pedestrians an
hour) pedestrians utilize the streets at night.
Typical are downtown office areas, blocks with
libraries, apartments, neighborhood shopping,
industrial, parks, and streets with transit lines.
LOW:
Areas with very low volumes (10 or fewer
pedestrians per hour) of night pedestrian usage.
A low pedestrian classification can occur in any
street classifications but may be typified by
suburban streets with single-family dwellings,
very low-density residential developments, and
rural or semi-rural areas.
DETERMINING PEDESTRIAN ACTIVITY LEVELS
13
LIGHTING DESIGN PROCESSPURPOSE
This section applies to new installations of
public street and pedestrian lighting, either
standalone or on traffic signal installations,
and modifications to existing street lighting
installations that affect pole types or locations,
excluding minor maintenance work. Refer to
Volume 2: Minimal Improvements for projects
involving 1-for-1 luminaire replacement and
supplemental improvements.
LIGHTING DESIGN PROCESS
Performing a lighting design for new installations
of streetlights is an iterative process. This
occurs because the lighting design is altered
(spacing, arrangement, mounting height) until
the target goal is met, per criteria set forth in
this document, for the specific street. The most
efficient method is to calculate luminance for
straight streets or illuminance for intersections
and non-straight streets, along with sidewalks
and other pedestrian areas with varying
luminaire parameters. The selected luminaire
must comply with the lumen output, efficacy,
BUG ratings, and other luminaire requirements
specified in Volume 2. Care should be taken,
when selecting a luminaire to illuminate the
surrounding sidewalks and public spaces
without causing light trespass, or unwanted
light spills onto surrounding properties and
through residential windows. Instructions on
setting up the lighting design calculations are
found later in this volume.
Lighting designers should use the Lighting
Warrants Table to determine the appropriate
strategy based on street classification, adjacent
land use, and pedestrian conflict. Once the
appropriate lighting strategy is determined,
designers can find lighting and luminaire criteria
and spacing guidance in the corresponding
sheets below. All lighting layouts for each street
classification are broken out below and should
be referenced during the design process.
LIGHTING APPLICATIONS
The following pages describe the luminaire
selection and lighting layout for each street
classification as defined by the Salt Lake City
Transportation Division. Designers should strive
to meet the luminaire spacing that will provide
the highest quality street lighting possible, but
this is not always feasible. It is necessary to
integrate lighting locations in correspondence
to other improvements:
• Clearance from driveways (10 feet
commercial and 5 feet residential).
• Clearance from fire hydrants (5 feet).
• Trees (centered in between trees or 20 feet
from the tree trunk).
• Streetlight offset should be a minimum of
3’-0” and a maximum of 8’-0” from back of
curb.
• Pedestrian lights should be a minimum
of 1’-0” and a maximum of 6’-0” from the
sidewalk.
• Light standards integrated into sidewalk
should maintain a minimum of 5’-0” clear
zone.
• Light standards should be located a
minimum distance of 10’-0” from trees.
Place poles and luminaires near property lines
wherever practical and avoid locations in front
of doorways, windows, and lines of egress.
COMPREHENSIVE IMPROVEMENTS
14
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
INTERSECTIONS & CROSSWALKS
The same luminaires are to be used throughout
the intersection. When an intersection is
between two different street classifications,
the higher street classification target criteria
is used throughout the entire intersection.
The recommended streetlight layout for an
intersection also depends on whether the
street classification calls for continuous or non-
continuous lighting.
The following requirements are recommended
to guide all traffic signal mounted streetlights.
The intersection design should ensure that the
crosswalks are sufficiently lighted to light the
vertical surface (body) of pedestrians in the
crosswalk. This may require that additional
streetlights be located before the intersection
as shown in the Figures 3 and 4 below.
Mid-block crossings and denoted crosswalks are
recommended to always be lighted. Crosswalks
can be denoted by striping, signage, flashing
beacons, etc. Crosswalks are important parts
of the streetscape and an appropriate lighting
design will improve the visibility of pedestrians
in the crosswalk. The lighting should be installed
between the vehicle and the crosswalk (ie: half to
one pole height before the crosswalk) to ensure
that the body of the pedestrian is adequately
lighted. If streetlights are installed above or
immediately adjacent to the crosswalk, only
the top of the pedestrian’s head will be lighted
making it difficult for motorists to see the
pedestrian. Crosswalks and mid-block crossings
are recommended to be lighted to the Vertical
Illuminance requirements in the table below.
Vertical illuminance measurements are taken
5ft. above the roadway surface in the direction
of oncoming traffic.
Figure 3: Streetlight Located Before Crosswalk Figure 4: Streetlight Placement with Respect to
Crosswalk
15
LIGHTING DESIGN PROCESSTABLE 4: INTERSECTION & CROSSWALK TARGET HORIZONTAL CRITERIA PER IES RP-8-18
STREET
CLASS
PED
CONFLICT
AVERAGE
HORIZONTAL
ILLUMINANCE
(FC)
UNIFORMITY
RATIO
(FCAVG/
FCMIN)
AVERAGE
VERTICAL
ILLUMINANCE
(FC)
MOUNTING
HEIGHT
(FEET)
MAST ARM
LENGTH
(FT)
DISTRIBUTION MAX BUG
RATING
LUMEN OUTPUT
RANGE
Arterial /
Arterial
High 3.4 3 1.4 35-40 10 Type 2 or 3 3-0-3 16,000-25,000
Medium 2.6 3 0.9 35-40 10 Type 2 or 3 3-0-3 10,000-16,000
Low 1.8 3 0.5 30-40 10 Type 2 or 3 2-0-2 7,000-12,000
Arterial /
Collector
High 2.9 3 0.9 35-40 10 Type 2 or 3 3-0-3 10,000-18,000
Medium 2.2 3 0.6 35-40 10 Type 2 or 3 2-0-2 8,500-13,500
Low 1.5 3 0.4 30-40 10 Type 2 or 3 2-0-2 5,000-10,000
Arterial /
Local
High 2.6 3 0.8 30-35 10 Type 2 or 3 3-0-3 10,000-16,000
Medium 2.0 3 0.6 30-35 10 Type 2 or 3 2-0-2 7,500-12,500
Low 1.3 3 0.4 30-35 10 Type 2 or 3 2-0-2 4,000-8,500
Collector
/ Collec-
tor
High 2.4 4 0.7 30-35 6 Type 2 or 3 2-0-2 7,500-12,000
Medium 1.8 4 0.5 30-35 6 Type 2 or 3 2-0-2 4,500-7,500
Low 1.2 4 0.5 30-35 6 Type 2 or 3 1-0-2 3,500-6,000
Collector
/ Local
High 2.1 4 0.6 30-35 6 Type 2 or 3 2-0-2 6,000-10,500
Medium 1.6 4 0.5 30-35 6 Type 2 or 3 1-0-2 4,000-7,000
Low 1.0 4 0.3 30-35 6 Type 2 or 3 1-0-2 3,000-5,500
Local /
Local
>30mph
High 1.8 6 0.5 25-30 6 Type 2 or 3 2-0-2 5,000-8,000
Medium 1.4 6 0.4 25-30 6 Type 2 or 3 1-0-1 4,000-6,000
Low 1.0 6 0.2 25-30 6 Type 2 or 3 1-0-1 3,000-5,500
Local /
Local
<30mph
High N/A
Medium N/A
Low N/A
* A U2 BUG rating is acceptable when using a house side shield?
1. Arterial mid block crossing shall follow the arterial/arterial intersection criteria.
2. Collector mid block crossing shall follow the collector/collector intersection criteria.
16
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
SIGNALIZED/CONTINUOUS LIGHTING
For a signalized intersection with continuous lighting the typical streetlight arrangement is
interrupted by placing streetlight signal poles. This is called out as “1/2 to 1 mounting height to
centerline of crosswalk (Typical)” in Figure 5 below. Additional streetlights should be located on
signal poles if additional lighting is needed to meet the intersection criteria.
Figure 5: Typical Intersection Lighting Layout with Signals and Continuous Lighting
NON- SIGNALIZED/CONTINUOUS LIGHTING
For a non-signalized intersection with continuous lighting the typical streetlight arrangement is
continued through the intersection (see Figure 6). The streetlights should be located along the
approach to the crosswalk, if it exists, installed half to one luminaire mounting height in front of
the crosswalk, between approaching vehicles and pedestrians.
Figure 6: Typical Intersection Lighting Layout with No Signals and Continuous Lighting
17
LIGHTING DESIGN PROCESSSIGNALIZED/NON-CONTINUOUS LIGHTING
For signalized intersections with non-continuous lighting luminaires are located half to one
luminaire mounting height in front of the crosswalk, illuminating the approach to the intersection.
If these four luminaires do not provide sufficient lighting throughout the entire intersection, two
more additional luminaires may be used, to be mounted on the signals as shown in Figure 7.
Figure 7: Typical Intersection Lighting Layout with Signals and Non-Continuous
Lighting
NON-SIGNALIZED/NON-CONTINUOUS LIGHTING
For streets with non-continuous lighting and no signals, one luminaire is to be placed at each
intersection, as shown in Figure 8. Refer to the Local Street chapter for more information.
Figure 8: Typical Intersection Lighting Layout with No Signals and Non-Continuous
Lighting
18
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
MID-BLOCK CROSSWALKS
The standard is a streetlight located one half to 1 mounting height in front of the crosswalk on both
sides of the street for all mid-block crossings, shown in Figures 9 and 10.
Figure 9: Streetlight Placement with Respect to Mid-Block Crossing
Figure 10: Cactus Pole Placement with Respect to Mid-Block Crossing
19
LIGHTING DESIGN PROCESSCACTUS POLE LAYOUTS
Cactus Poles within downtown SLC should be upgraded to fully shielded LED luminaires. The
Cactus Pole locations and spacing will not change, but the lumen output and distribution of
new luminaire should meet the criteria in Table 7 and 8 based on the location of the lighting
improvements seen in Figure 11 and 12.
Figure 11: Cactus Pole Lighting Layouts
Striped
Median
℄
Walk Tree
Lawn
Bike
Street Width
Parking Drive
Lane
Drive
Lane
℄
WalkTree
Lawn
Bike ParkingDrive
Lane
Drive
Lane
CACTUS POLESFigure 12: Cactus Pole Sections
TABLE 5: ARTERIAL STREET TARGET CRITERIA PER IES RP-8-18
PEDESTRIAN ACTIVITY ROADWAY SIDEWALKS
AVERAGE LUMINANCE (CD/M2)LUMINANCE AVG:MIN RATIO AVERAGE ILLUMINANCE (FC)
High 1.2 3:1 1.0
Medium 0.9 3:1 0.5
TABLE 6: COLLECTOR STREET TARGET CRITERIA PER IES RP-8-18
PEDESTRIAN ACTIVITY ROADWAY SIDEWALKS
AVERAGE LUMINANCE (CD/M2)LUMINANCE AVG:MIN RATIO AVERAGE ILLUMINANCE (FC)
High 0.8 3:1 1.0
Medium 0.6 4:1 0.5
20
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
TABLE 7: RECOMMENDED CACTUS POLE LUMINAIRE CRITERIA – ARTERIAL STREETS
STREET
WIDTH
PEDESTRIAN
ACTIVITY
STREET LIGHT
LUMEN OUTPUT (LM)
STREET LIGHT
PHOTOMETRIC
DISTRIBUTION
MAX. STREET
LIGHT BUG
RATING
PEDESTRIAN
LIGHT LUMEN
OUTPUT (LM)
PEDESTRIAN
LIGHT
PHOTOMETRIC
DISTRIBUTION
MAX.
PEDESTRIAN
LIGHT BUG
RATING
70-90
High 8,500-10,500 Type III or IV B3-U0-G2*3,000-
5,000 Type III or IV B1-U0-G1
Medium 5,500-9,000 Type III B3-U0-G2*
3,000-
5,000 Type III B1-U0-G1
90-110
High 6,500-9,500 Type II B3-U0-G2*
3,500-
5,500 Type III B1-U0-G1
Medium 8,000-11,500 Type III B3-U0-G2*
2,500-
5,000 Type II or III B1-U0-G1
TABLE 8: RECOMMENDED CACTUS POLE LUMINAIRE CRITERIA – COLLECTOR STREETS
STREET
WIDTH
PEDESTRIAN
ACTIVITY
STREET LIGHT
LUMEN OUTPUT (LM)
STREET LIGHT
PHOTOMETRIC
DISTRIBUTION
MAX. STREET
LIGHT BUG
RATING
PEDESTRIAN
LIGHT LUMEN
OUTPUT (LM)
PEDESTRIAN
LIGHT
PHOTOMETRIC
DISTRIBUTION
MAX.
PEDESTRIAN
LIGHT BUG
RATING
70-90
High 5,500-8,500 Type III or IV B2-U0-G2 2,500-
4,500 Type III or IV B1-U0-G1
Medium 4,500-8,000 Type II or IV B2-U0-G2
2,500-
4,500 Type III or IV B1-U0-G1
90-110
High 9,000-11,500 Type III B3-U0-G2
3,000-
5,000 Type III or IV B1-U0-G1
Medium 4,500-7,500 Type III or IV B2-U0-G2
3,000-
5,000 Type III or IV B1-U0-G1
* These BUG Ratings apply to all Cactus Pole lights, except at intersections and mid-block pedestrian crossings,
which may have B3-U3-G2 Ratings to provide adequate vertical illuminance at crosswalks.”
21
LIGHTING DESIGN PROCESSStreet Width
Walk Tree
Lawn
Striped
Median
Drive
Lane
Drive
Lane
℄
WalkTree
Lawn
Drive
Lane
Drive
Lane
SUGARHOUSE TEAR DROP
SUGARHOUSE POLE LAYOUT
The teardrop luminaires in the Sugarhouse Business District should be upgraded to fully shielded
LED luminaires. The locations and spacing will not change, but the lumen output and distribution
of new luminaire should meet the criteria in Table 10. This is illustrated in Figures 13 and 14.
Figure 13: Sugarhouse Pole Lighting Layouts
Figure 14: Sugarhouse Pole Lighting Section
22
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
TABLE 9: ARTERIAL STREET TARGET CRITERIA PER IES RP-8-18
PEDESTRIAN ACTIVITY ROADWAY SIDEWALKS
AVERAGE LUMINANCE (CD/M2)LUMINANCE AVG:MIN RATIO AVERAGE ILLUMINANCE (FC)
High 1.2 3:1 1.0
Medium 0.9 3:1 0.5
TABLE 10: RECOMMENDED SUGARHOUSE POLE LUMINAIRE CRITERIA
PEDESTRIAN
ACTIVITY
STREET LIGHT
LUMEN OUTPUT (LM)
STREET LIGHT
PHOTOMETRIC
DISTRIBUTION
MAX. STREET
LIGHT BUG
RATING
PEDESTRIAN LIGHT
LUMEN OUTPUT (LM)
PEDESTRIAN LIGHT
PHOTOMETRIC
DISTRIBUTION
MAX.
PEDESTRIAN
LIGHT BUG
RATING
High 6,000-8,000 Type II or III B2-U0-G2 2,000-3,000 Type II or III B1-U0-G1
Medium 3,000-7,000 Type II or III B2-U0-G1 1,000-2,000 Type II or III B1-U0-G1
23
LIGHTING DESIGN PROCESSTEAR DROP POLE LAYOUT
The teardrop luminaires along South Temple and State Street should be upgraded to fully shielded
LED luminaires. The locations and spacing will not change, but the lumen output and distribution
of new luminaire should meet the criteria in Table 12. This is illustrated in Figures 15 and 16.
Figure 15: Tear Drop Lighting Layouts
Figure 16: Tear Drop Lighting Section
Street Width
Striped
Median
Drive
Lane
℄
Drive
Lane
Drive
Lane WalkBikeParking
Walk Tree
Lawn
Tree
Lawn
Drive
Lane
Drive
Lane
Drive
Lane Bike Parking
S TEMPLE STATE ST TEAR
DROP
24
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
TABLE 11: ARTERIAL STREET TARGET CRITERIA PER IES RP-8-18
PEDESTRIAN ACTIVITY ROADWAY SIDEWALKS
AVERAGE LUMINANCE (CD/M2)LUMINANCE AVG:MIN RATIO AVERAGE ILLUMINANCE (FC)
High 1.2 3:1 1.0
Medium 0.9 3:1 0.5
Low 0.6 4:1 0.4
TABLE 12: RECOMMENDED TEAR DROP LUMINAIRE CRITERIA
STREET
WIDTH PEDESTRIAN ACTIVITY LUMEN OUTPUT (LM)TYPICAL PHOTOMETRIC
DISTRIBUTION MAX. BUG RATING
50-70
High 11,000-14,750 Type III B2-U0-G2
Medium 8,500-12,000 Type III B2-U0-G2
Low 5,500-8,500 Type III B2-U0-G2
70-
100
High 16,500-20,500 Type III B3-U0-G3
Medium 16,500-20,500 Type III B3-U0-G3
Low 11,000-16,500 Type III B2-U0-G2
25
LIGHTING DESIGN PROCESSARTERIAL STREET – CONTINUOUS STREET LIGHTING
The figures and tables below provide direction on the appropriate luminaire selection and non-
median lighting layout when designing an arterial street with only street lighting. Luminaires are
to be placed in an opposite arrangement when not located at an intersection, Figures 17 and 18.
Figure 17: Typical Arterial with Continuous Street Lighting Plan
Figure 18: Typical Arterial with Continuous Street Lighting Cross Section
26
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
TABLE 13: ARTERIAL STREET TARGET CRITERIA PER IES RP-8-18
PEDESTRIAN ACTIVITY ROADWAY SIDEWALKS
AVERAGE LUMINANCE (CD/M2)LUMINANCE AVG:MIN RATIO AVERAGE ILLUMINANCE (FC)
High 1.2 3:1 1.0
Medium 0.9 3:1 0.5
Low 0.6 4:1 0.4
TABLE 14: RECOMMENDED ARTERIAL (NON-MEDIAN MOUNTED) LUMINAIRE & POLE CRITERIA
STREET
WIDTH
(FT)
PEDESTRIAN
ACTIVITY POLE SPACING (FT)POLE HEIGHT
(FT)LUMEN OUTPUT (LM)
TYPICAL
PHOTOMETRIC
DISTRIBUTION
MAX. BUG RATING
50-70
High
120-140 30-35 6,500-9,000 Type II or III B2-U0-G2
140-180 30-35 8,500-14,000 Type II or III B3-U0-G2
Medium 140-180 30-35 6,500-9,000 Type II or III B2-U0-G2
180-220 30-35 8,500-10,000 Type II or III B2-U0-G2
Low 180-220 30-35 6,000-8,500 Type II or III B2-U0-G2
70-90
High 140-180 30-35 8,500-12,000 Type II or III B2-U0-G2
180-220 30-35 12,000-18,000 Type II or III B3-U0-G3
Medium 120-160 30-35 7,500-10,000 Type II or III B2-U0-G2
160-200 30-35 8,500-12,000 Type II or III B3-U0-G2
Low 140-180 30-35 6,500-9,500 Type II or III B2-U0-G2
180-220 30-35 7,500-11,000 Type II or III B2-U0-G2
90-110
High 120-160 30-35 11,000-18,000 Type II B3-U0-G3
Medium 140-180 30-35 10,000-18,000 Type II or III B2-U0-G2
180-220 30-35 15,000-19,000 Type II or III B3-U0-G3
Low 140-180 30-35 8,000-13,000 Type II or III B2-U0-G2
180-220 30-35 12,000-14,500 Type II or III B2-U0-G2
27
LIGHTING DESIGN PROCESSARTERIAL STREET – NON-CONTINUOUS STREET LIGHTING
The figures and tables below provide direction on the appropriate luminaire selection and non-
median lighting layout when designing an arterial street with non-continuous street. Street
luminaires are to be placed in an opposite arrangement when not located at an intersection,
Figures 19 and 20.
Figure 19: Typical Arterial with Non-Continuous Street Lighting Plan
Figure 20: Typical Arterial with Non-Continuous Street Lighting Cross Section
12 TO 1 MOUNTING HEIGHT TO
CENTERLINE OF CROSSWALK
(TYPICAL)
SIGNAL-MOUNTED
LUMINAIRE (TYP)
Striped
MedianDrive
Lane
Bike/
Shoulder/
Parking
Drive
LaneWalkTree
Lawn
Drive
Lane
Bike/
Shoulder/
Parking
Drive
Lane WalkTree
Lawn
Street Width
ARTERIAL STREET LIGHTING ONLY
MAX SPACING TO BE DOUBLE RECOMMENDED
SPACING FOR CONTINUOUS LIGHTING
12 TO 1 MOUNTING HEIGHT TO
CENTERLINE OF CROSSWALK
(TYPICAL)
Striped
MedianDrive
Lane
Bike/
Shoulder/
Parking
Drive
LaneWalk Tree
Lawn
Drive
Lane
Bike/
Shoulder/
Parking
Drive
Lane WalkTree
Lawn
Street Width
ARTERIAL NON CONTINUOUS
STREET LIGHTING
28
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
TABLE 15: RECOMMENDED ARTERIAL (NON-MEDIAN MOUNTED) LUMINAIRE & POLE CRITERIA
STREET
WIDTH
PEDESTRIAN
ACTIVITY POLE SPACING (FT)POLE HEIGHT
(FT)LUMEN OUTPUT (LM)
TYPICAL
PHOTOMETRIC
DISTRIBUTION
MAX. BUG RATING
50-70 Medium 240-280 30-35 6,500-9,000 Type II or III B2-U0-G2
280-360 30-35 8,500-10,000 Type II or III B2-U0-G2
Low 360-440 30-35 6,000-8,500 Type II or III B2-U0-G2
70-90
Medium 240-320 30-35 7,500-10,000 Type II or III B2-U0-G2
320-400 30-35 8,500-12,000 Type II or III B3-U0-G2
Low 280-360 30-35 6,500-9,500 Type II or III B2-U0-G2
360-440 30-35 7,500-11,000 Type II or III B2-U0-G2
90-110
Medium 280-360 30-35 10,000-18,000 Type II or III B2-U0-G2
360-440 30-35 15,000-19,000 Type II or III B3-U0-G3
Low 280-360 30-35 8,000-13,000 Type II or III B2-U0-G2
360-440 30-35 12,000-14,500 Type II or III B2-U0-G2
29
LIGHTING DESIGN PROCESSARTERIAL STREET – CONTINUOUS STREET LIGHTING AND CONTINUOUS PEDESTRIAN LIGHTING
The figures and tables below provide direction on the appropriate luminaire selection and non-
median lighting layout when designing an arterial street with continuous street and pedestrian
lighting. Street lights are to be placed in an opposite arrangement when not located at an
intersection. Pedestrian lights should be coordinated with the landscape and street lighting
layouts to maintain a consistent spacing, Figures 21 and 22.
Figure 21: Typical Arterial with Continuous Street and Pedestrian Lighting Plan
Figure 22: Typical Arterial with Continuous Street and Pedestrian Lighting Cross Section
12 TO 1 MOUNTING HEIGHT TO
CENTERLINE OF CROSSWALK
(TYPICAL)
Striped
MedianDrive
Lane
Bike/
Shoulder/
Parking
Drive
LaneWalk Tree
Lawn
Drive
Lane
Bike/
Shoulder/
Parking
Drive
Lane WalkTree
Lawn
Street Width
ARTERIAL CONT STREET AND PEDZ:\18060 Salt Lake Street Lighting Master Plan\CAD\Roadway plans for masterplan.dwg, 6/17/2020 9:58:29 AM, DWG To PDF.pc3
12 TO 1 MOUNTING HEIGHT TO
CENTERLINE OF CROSSWALK
(TYPICAL)
Striped
MedianDrive
Lane
Bike/
Shoulder/
Parking
Drive
LaneWalkTree
Lawn
Drive
Lane
Bike/
Shoulder/
Parking
Drive
Lane WalkTree
Lawn
Street Width
ARTERIAL CONT STREET AND PEDZ:\18060 Salt Lake Street Lighting Master Plan\CAD\Roadway plans for masterplan.dwg, 6/17/2020 9:58:29 AM, DWG To PDF.pc3
30
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
TABLE 16: ARTERIAL STREET TARGET CRITERIA PER IES RP-8-18
PEDESTRIAN ACTIVITY ROADWAY SIDEWALKS
AVERAGE LUMINANCE (CD/M2)LUMINANCE AVG:MIN RATIO AVERAGE ILLUMINANCE (FC)
High 1.2 3:1 1.0
TABLE 17: RECOMMENDED ARTERIAL (NON-MEDIAN MOUNTED) STREET LUMINAIRE & POLE CRITERIA
STREET
WIDTH
PEDESTRIAN
ACTIVITY POLE SPACING (FT)POLE HEIGHT
(FT)LUMEN OUTPUT (LM)
TYPICAL
PHOTOMETRIC
DISTRIBUTION
MAX. BUG RATING
50-70 High
120-140 30-35 6,500-9,000 Type II or III B2-U0-G2
140-180 30-35 8,500-14,000 Type II or III B3-U0-G2
70-90 High 140-180 30-35 8,500-12,000 Type II or III B2-U0-G2
180-220 30-35 12,000-18,000 Type II or III B3-U0-G3
90-110 High 120-160 30-35 11,000-18,000 Type II B3-U0-G3
TABLE 18: RECOMMENDED ARTERIAL (NON-MEDIAN MOUNTED) PEDESTRIAN LUMINAIRE & POLE CRITERIA
PEDESTRIAN
ACTIVITY POLE SPACING (FT)POLE HEIGHT
(FT)LUMEN OUTPUT (LM)
TYPICAL
PHOTOMETRIC
DISTRIBUTION
MAX. BUG RATING
High 50-80 12-15 3,000-5,500 Type II or III B1-U2-G1
31
LIGHTING DESIGN PROCESSARTERIAL STREET – CONTINUOUS STREET LIGHTING AND NON-CONTINUOUS PEDESTRIAN LIGHTING
The figures and tables below provide direction on the appropriate luminaire selection and non-
median lighting layout when designing an arterial street with continuous street lighting and non-
continuous pedestrian lighting. Street luminaires are to be placed in an opposite arrangement
when not located at an intersection. Pedestrian luminaire should be located to illuminate locations
shadowed by trees or at vehicle-pedestrian conflict points, Figures 23 and 24.
Figure 23: Typical Arterial with Continuous Street Lighting and Non-Continuous Pedestrian Lighting Plan
Figure 24: Typical Arterial with Continuous Street Lighting and Non-Continuous Pedestrian Lighting Cross Section
12 TO 1 MOUNTING HEIGHT TO
CENTERLINE OF CROSSWALK
(TYPICAL)
Striped
MedianDrive
Lane
Bike/
Shoulder/
Parking
Drive
LaneWalk Tree
Lawn
Drive
Lane
Bike/
Shoulder/
Parking
Drive
Lane WalkTree
Lawn
Street Width
ARTERIAL CONT STREET AND NON CONT. PEDZ:\18060 Salt Lake Street Lighting Master Plan\CAD\Roadway plans for masterplan.dwg, 6/17/2020 9:58:35 AM, DWG To PDF.pc3
12 TO 1 MOUNTING HEIGHT TO
CENTERLINE OF CROSSWALK
(TYPICAL)
Striped
MedianDrive
Lane
Bike/
Shoulder/
Parking
Drive
LaneWalkTree
Lawn
Drive
Lane
Bike/
Shoulder/
Parking
Drive
Lane WalkTree
Lawn
Street Width
ARTERIAL CONT STREET AND NON CONT. PEDZ:\18060 Salt Lake Street Lighting Master Plan\CAD\Roadway plans for masterplan.dwg, 6/17/2020 9:58:35 AM, DWG To PDF.pc3
32
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
TABLE 19: ARTERIAL STREET TARGET CRITERIA PER IES RP-8-18
PEDESTRIAN ACTIVITY ROADWAY SIDEWALKS
AVERAGE LUMINANCE (CD/M2)LUMINANCE AVG:MIN RATIO AVERAGE ILLUMINANCE (FC)
High 1.2 3:1 1.0
Medium 0.9 3:1 0.5
Low 0.6 4:1 0.4
TABLE 20: RECOMMENDED ARTERIAL (NON-MEDIAN MOUNTED) LUMINAIRE & POLE CRITERIA
STREET
WIDTH
(FT)
PEDESTRIAN
ACTIVITY POLE SPACING (FT)POLE HEIGHT
(FT)LUMEN OUTPUT (LM)
TYPICAL
PHOTOMETRIC
DISTRIBUTION
MAX. BUG RATING
50-70
High 120-140 30-35 6,500-9,000 Type II or III B2-U0-G2
140-180 30-35 8,500-14,000 Type II or III B3-U0-G2
Medium 140-180 30-35 6,500-9,000 Type II or III B2-U0-G2
180-220 30-35 8,500-10,000 Type II or III B2-U0-G2
Low 180-220 30-35 6,000-8,500 Type II or III B2-U0-G2
70-90
High 140-180 30-35 8,500-12,000 Type II or III B2-U0-G2
180-220 30-35 12,000-18,000 Type II or III B3-U0-G3
Medium 120-160 30-35 7,500-10,000 Type II or III B2-U0-G2
160-200 30-35 8,500-12,000 Type II or III B3-U0-G2
Low 140-180 30-35 6,500-9,500 Type II or III B2-U0-G2
180-220 30-35 7,500-11,000 Type II or III B2-U0-G2
90-110
High 120-160 30-35 11,000-18,000 Type II B3-U0-G3
Medium 140-180 30-35 10,000-18,000 Type II or III B2-U0-G2
180-220 30-35 15,000-19,000 Type II or III B3-U0-G3
Low 140-180 30-35 8,000-13,000 Type II or III B2-U0-G2
180-220 30-35 12,000-14,500 Type II or III B2-U0-G2
TABLE 21: RECOMMENDED ARTERIAL (NON-MEDIAN MOUNTED) PEDESTRIAN LUMINAIRE & POLE CRITERIA
PEDESTRIAN
ACTIVITY POLE SPACING (FT)POLE HEIGHT
(FT)LUMEN OUTPUT (LM)TYPICAL PHOTOMETRIC
DISTRIBUTION MAX. BUG RATING
High 50-80 12-15 3,000-5,500 Type II or III B1-U2-G1
Medium 50-80 12-15 3,000-5,000 Type II or III B1-U0-G1
80-120 12-15 3,000-5,500 Type II or III B1-U0-G1
Low 50-80 12-15 2,000-4,500 Type II or III B1-U0-G1
80-120 12-15 2,500-5,500 Type II or III B1-U0-G1
33
LIGHTING DESIGN PROCESSARTERIAL STREET – INTERSECTION ONLY LIGHTING
The figures and tables below provide direction on the appropriate luminaire selection and
non-median lighting layout when designing an arterial street with intersection only street light-
ing. Street luminaires are to be placed at the intersection with luminaire on half to one mounting
height in front of any existing crosswalks, Figures 25 and 26.
Figure 25: Typical Arterial with Street Lights at Intersections Only Plan
Figure 26: Typical Arterial with Street Lights at Intersections Only Cross Section
12 TO 1 MOUNTING HEIGHT TO
CENTERLINE OF CROSSWALK
(TYPICAL)
Striped
MedianDrive
Lane
Bike/
Shoulder/
Parking
Drive
LaneWalkTree
Lawn
Drive
Lane
Bike/
Shoulder/
Parking
Drive
Lane WalkTree
Lawn
Street Width
ARTERIAL STREET INT. ONL
12 TO 1 MOUNTING HEIGHT TO
CENTERLINE OF CROSSWALK
(TYPICAL)
Striped
MedianDrive
Lane
Bike/
Shoulder/
Parking
Drive
LaneWalkTree
Lawn
Drive
Lane
Bike/
Shoulder/
Parking
Drive
Lane WalkTree
Lawn
Street Width
ARTERIAL STREET INT. ONL
See Intersections & Crosswalks Section on page 14 for lighting criteria and luminaire recom-
mendations.
34
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
COLLECTOR STREET – CONTINUOUS STREET LIGHTING
The figures and tables below provide direction on the appropriate luminaire selection and non-
median lighting layout when designing a collector street with only street lighting. Luminaires are
to be placed in an opposite arrangement when not located at an intersection, Figures 27 and 28.
Figure 27: Typical Collector Street with Continuous Street Lighting
Figure 28: Typical Cross Section for Collector with Continuous Street Lighting
12 TO 1 MOUNTING HEIGHT TO
CENTERLINE OF CROSSWALK
(TYPICAL)
Travel
Lane
℄
Sidewalk &
Park Strip
Travel
Lane
Striped
Median
Street Width
Travel
Lane
Sidewalk &
Park Strip
Travel
Lane
COLLECTOR STREET LIGHTING ONLY
12 TO 1 MOUNTING HEIGHT TO
CENTERLINE OF CROSSWALK
(TYPICAL)
Travel
Lane
℄
Sidewalk &
Park Strip
Travel
Lane
Striped
Median
Street Width
Travel
Lane
Sidewalk &
Park Strip
Travel
Lane
COLLECTOR STREET LIGHTING ONLY
35
LIGHTING DESIGN PROCESSTABLE 22: ARTERIAL STREET TARGET CRITERIA PER IES RP-8-18
PEDESTRIAN ACTIVITY ROADWAY SIDEWALKS
AVERAGE LUMINANCE (CD/M2)LUMINANCE AVG:MIN RATIO AVERAGE ILLUMINANCE (FC)
High 0.8 3:1 1.0
Medium 0.6 4:1 0.5
TABLE 23: RECOMMENDED COLLECTOR STREET LUMINAIRE AND POLE SPACING CRITERIA
ROADWAY
WIDTH (FT)
PEDESTRIAN
ACTIVITY
POLE SPACING
(FT)
POLE HEIGHT
(FT)LUMEN OUTPUT (LM)
TYPICAL
PHOTOMETRIC
DISTRIBUTION
MAX. BUG RATING
30-50
High 140-160 30 6,500-7,800 Type II or III B2-U0-G2
180-220 30 7,000-10,000 Type II or III B2-U0-G2
Medium 140-160 30 5,000-7,000 Type II or III B2-U0-G2
180-220 30 6,500-8,800 Type II or III B2-U0-G2
50-70
High 140-160 30 6,500-8,000 Type II or III B2-U0-G2
180-220 30 7,000-9,000 Type II or III B2-U0-G2
Medium 140-160 30 6,000-7,700 Type II or III B2-U0-G2
180-220 30 7,000-8,700 Type II or III B2-U0-G2
70-100
High 120-140 30 8,500-12,000 Type II or III B2-U0-G2
Medium 140-160 30 7,000-10,000 Type II or III B2-U0-G2
180-220 30 9,000-13,000 Type II or III B2-U0-G2
36
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
COLLECTOR STREET – NON-CONTINUOUS STREET LIGHTING
The figures and tables below provide direction on the appropriate luminaire selection and non-
median lighting layout when designing a collector street with non-continuous street lighting.
Luminaires are to be placed in an opposite arrangement when not located at an intersection,
Figures 29 and 30.
Figure 29: Typical Collector Street with Non-Continuous Street Lighting
Figure 30: Typical Collector Street with Non-Continuous Lighting Cross Section
12 TO 1 MOUNTING HEIGHT TO
CENTERLINE OF CROSSWALK
(TYPICAL)
Travel
Lane
℄
Sidewalk &
Park Strip
Travel
Lane
Striped
Median Travel
Lane
Sidewalk &
Park Strip
Travel
Lane
Street Width
COLLECTOR NON CONTINUOUS STREETZ:\18060 Salt Lake Street Lighting Master Plan\CAD\Roadway plans for masterplan.dwg, 6/17/2020 9:58:40 AM, DWG To PDF.pc3
12 TO 1 MOUNTING HEIGHT TO
CENTERLINE OF CROSSWALK
(TYPICAL)
Travel
Lane
℄
Sidewalk &
Park Strip
Travel
Lane
Striped
Median Travel
Lane
Sidewalk &
Park Strip
Travel
Lane
Street Width
COLLECTOR NON CONTINUOUS STREETZ:\18060 Salt Lake Street Lighting Master Plan\CAD\Roadway plans for masterplan.dwg, 6/17/2020 9:58:40 AM, DWG To PDF.pc3
37
LIGHTING DESIGN PROCESSTABLE 24: RECOMMENDED COLLECTOR STREET LUMINAIRE AND POLE SPACING CRITERIA
ROADWAY
WIDTH (FT)
PEDESTRIAN
ACTIVITY
POLE SPACING
(FT)
POLE HEIGHT
(FT)LUMEN OUTPUT (LM)
TYPICAL
PHOTOMETRIC
DISTRIBUTION
MAX. BUG RATING
30-50
Medium 280-320 30 5,000-7,000 Type II or III B2-U0-G2
320-440 30 6,500-8,800 Type II or III B2-U0-G2
Low 280-360 30 4,000-5,500 Type III B1-U0-G1
360-440 30 4,500-6,000 Type III B1-U0-G1
50-70
Medium 280-320 30 6,000-7,700 Type II or III B2-U0-G2
320-440 30 7,000-8,700 Type II or III B2-U0-G2
Low 280-320 30 4,000-5,500 Type II or III B2-U0-G1
320-440 30 5,000-8,000 Type II or III B2-U0-G2
70-100
Medium 280-320 30 7,000-10,000 Type II or III B2-U0-G2
320-440 30 9,000-13,000 Type II or III B2-U0-G2
Low 280-360 30 6,500-9,000 Type II or III B2-U0-G2
360-440 30 6,500-10,000 Type II or III B2-U0-G2
38
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
COLLECTOR STREET – CONTINUOUS STREET AND CONTINUOUS PEDESTRIAN LIGHTING
The figures and tables below provide direction on the appropriate luminaire selection and non-
median lighting layout when designing a collector street with continuous street and pedestrian
lighting. Street luminaires are to be placed in an opposite arrangement when not located at
an intersection. Pedestrian lights should be coordinated with the landscape and street lighting
layouts to maintain a consistent spacing, Figures 31 and 32.
Figure 31: Typical Collector Street with Continuous Street and Pedestrian Lighting
Figure 32: Typical Collector with Continuous Street and Pedestrian Lighting
12 TO 1 MOUNTING HEIGHT TO
CENTERLINE OF CROSSWALK
(TYPICAL)
Travel
Lane
℄
Sidewalk &
Park Strip
Travel
Lane
Striped
Median Travel
Lane
Sidewalk &
Park Strip
Travel
Lane
Street Width
COLLECTOR CONT STREET & PEDZ:\18060 Salt Lake Street Lighting Master Plan\CAD\Roadway plans for masterplan.dwg, 6/17/2020 9:58:44 AM, DWG To PDF.pc3
12 TO 1 MOUNTING HEIGHT TO
CENTERLINE OF CROSSWALK
(TYPICAL)
Travel
Lane
℄
Sidewalk &
Park Strip
Travel
Lane
Striped
Median Travel
Lane
Sidewalk &
Park Strip
Travel
Lane
Street Width
COLLECTOR CONT STREET & PEDZ:\18060 Salt Lake Street Lighting Master Plan\CAD\Roadway plans for masterplan.dwg, 6/17/2020 9:58:44 AM, DWG To PDF.pc3
39
LIGHTING DESIGN PROCESSTABLE 25: ARTERIAL STREET TARGET CRITERIA PER IES RP-8-18
PEDESTRIAN ACTIVITY ROADWAY SIDEWALKS
AVERAGE LUMINANCE (CD/M2)LUMINANCE AVG:MIN RATIO AVERAGE ILLUMINANCE (FC)
High 0.8 3:1 1.0
TABLE 26: RECOMMENDED COLLECTOR STREET LUMINAIRE AND POLE SPACING CRITERIA
ROADWAY
WIDTH (FT)
PEDESTRIAN
ACTIVITY
POLE SPACING
(FT)
POLE HEIGHT
(FT)LUMEN OUTPUT (LM)
TYPICAL
PHOTOMETRIC
DISTRIBUTION
MAX. BUG RATING
30-50 High
140-180 30 6,500-7,800 Type II or III B2-U0-G2
180-220 30 7,000-10,000 B2-U0-G2
50-70 High 140-160 30 6,500-8,000 Type II or III B2-U0-G2
160-220 30 7,000-9,000 B2-U0-G2
70-100 High 120-140 30 8,500-12,000 Type II or III B2-U0-G2
TABLE 27: RECOMMENDED COLLECTOR PEDESTRIAN LUMINAIRE AND POLE SPACING CRITERIA
PEDESTRIAN
ACTIVITY
POLE SPACING
(FT)
POLE HEIGHT
(FT)LUMEN OUTPUT (LM)
TYPICAL
PHOTOMETRIC
DISTRIBUTION
MAX. BUG RATING
High 50-80 12-15 3,000-5,000 Type II or III B1-U2-G1
80-120 12-15 3,500-5,500 Type II or III B1-U2-G1
40
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
COLLECTOR STREET – CONTINUOUS STREET AND NON-CONTINUOUS PEDESTRIAN LIGHTING
The figures and tables below provide direction on the appropriate luminaire selection and non-
median lighting layout when designing a collector street with continuous street lighting and non-
continuous pedestrian lighting. Street luminaires are to be placed in an opposite arrangement
when not located at an intersection. Pedestrian luminaire should be located to illuminate locations
shadowed by trees or at vehicle-pedestrian conflict points, Figures 33 and 34.
Figure 33: Typical Collector Street with Continuous Street and Non-Continuous Pedestrian Lighting Plan
Figure 34: Typical Collector with Continuous Street and Non-Continuous Pedestrian Lighting Cross Section
12 TO 1 MOUNTING HEIGHT TO
CENTERLINE OF CROSSWALK
(TYPICAL)
Travel
Lane
℄
Sidewalk &
Park Strip
Travel
Lane
Striped
Median Travel
Lane
Sidewalk &
Park Strip
Travel
Lane
Street Width
COLLECTOR CONT STREET NON CONT PEDZ:\18060 Salt Lake Street Lighting Master Plan\CAD\Roadway plans for masterplan.dwg, 6/17/2020 9:58:49 AM, DWG To PDF.pc3
12 TO 1 MOUNTING HEIGHT TO
CENTERLINE OF CROSSWALK
(TYPICAL)
Travel
Lane
℄
Sidewalk &
Park Strip
Travel
Lane
Striped
Median Travel
Lane
Sidewalk &
Park Strip
Travel
Lane
Street Width
COLLECTOR CONT STREET NON CONT PEDZ:\18060 Salt Lake Street Lighting Master Plan\CAD\Roadway plans for masterplan.dwg, 6/17/2020 9:58:49 AM, DWG To PDF.pc3
41
LIGHTING DESIGN PROCESSTABLE 28: ARTERIAL STREET TARGET CRITERIA PER IES RP-8-18
PEDESTRIAN ACTIVITY ROADWAY SIDEWALKS
AVERAGE LUMINANCE (CD/M2)LUMINANCE AVG:MIN RATIO AVERAGE ILLUMINANCE (FC)
High 0.8 3:1 1.0
Medium 0.6 4:1 0.5
TABLE 30: RECOMMENDED COLLECTOR PEDESTRIAN LUMINAIRE AND POLE SPACING CRITERIA
PEDESTRIAN
ACTIVITY
POLE SPACING
(FT)
POLE HEIGHT
(FT)LUMEN OUTPUT (LM)
TYPICAL
PHOTOMETRIC
DISTRIBUTION
MAX. BUG RATING
High 50-80 12-15 3,000-5,000 Type II or III B1-U2-G1
80-120 12-15 3,500-5,500 Type II or III B1-U2-G1
Medium 50-80 12-15 2,000-4,000 Type II or III B1-U0-G1
80-120 12-15 2,500-5,000 Type II or III B1-U0-G1
TABLE 29: RECOMMENDED COLLECTOR STREET LUMINAIRE AND POLE SPACING CRITERIA
ROADWAY
WIDTH (FT)
PEDESTRIAN
ACTIVITY
POLE SPACING
(FT)
POLE HEIGHT
(FT)LUMEN OUTPUT (LM)
TYPICAL
PHOTOMETRIC
DISTRIBUTION
MAX. BUG RATING
30-50
High 140-180 30 6,500-7,800 Type II or III B2-U0-G2
180-220 30 7,000-10,000 Type II or III B2-U0-G2
Medium 140-160 30 5,000-7,000 Type II or III B2-U0-G2
160-220 30 6,500-8,800 Type II or III B2-U0-G2
50-70
High 140-160 30 6,500-8,000 Type II or III B2-U0-G2
160-220 30 7,000-9,000 Type II or III B2-U0-G2
Medium 140-160 30 6,000-7,700 Type II or III B2-U0-G2
160-220 30 7,000-8,700 Type II or III B2-U0-G2
70-100
High 120-140 30 8,500-12,000 Type II or III B2-U0-G2
Medium 140-160 30 7,000-10,000 Type II or III B2-U0-G2
160-220 30 9,000-13,000 Type II or III B2-U0-G2
42
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
COLLECTOR STREET – CONTINUOUS PEDESTRIAN LIGHTING
The figures and tables below provide direction on the appropriate luminaire selection and non-
median lighting layout when designing a collector street with continuous pedestrian lighting.
Pedestrian lights should be coordinated with the landscape and street lighting layouts to maintain
a consistent spacing, Figures 35 and 36.
Figure 35: Typical Collector Street with Continuous Pedestrian Lighting
Figure 36: Typical Collector with Continuous Pedestrian Lighting
12 TO 1 MOUNTING HEIGHT TO
CENTERLINE OF CROSSWALK
(TYPICAL)
60'-0"
Travel
Lane
℄
Sidewalk &
Park Strip
Travel
Lane
Striped
Median
ROW
Travel
Lane
Sidewalk &
Park Strip
Travel
Lane
COLLECTOR CONT PEDZ:\18060 Salt Lake Street Lighting Master Plan\CAD\Roadway plans for masterplan.dwg, 6/17/2020 9:58:57 AM, DWG To PDF.pc3
12 TO 1 MOUNTING HEIGHT TO
CENTERLINE OF CROSSWALK
(TYPICAL)
60'-0"
Travel
Lane
℄
Sidewalk &
Park Strip
Travel
Lane
Striped
Median
ROW
Travel
Lane
Sidewalk &
Park Strip
Travel
Lane
COLLECTOR CONT PEDZ:\18060 Salt Lake Street Lighting Master Plan\CAD\Roadway plans for masterplan.dwg, 6/17/2020 9:58:57 AM, DWG To PDF.pc3
See Intersection Section on page 46 for intersection lighting criteria and luminaire recommendations.
43
LIGHTING DESIGN PROCESSTABLE 31: RECOMMENDED COLLECTOR PEDESTRIAN LUMINAIRE AND POLE SPACING CRITERIA
PEDESTRIAN
ACTIVITY
POLE SPACING
(FT)
POLE HEIGHT
(FT)LUMEN OUTPUT (LM)
TYPICAL
PHOTOMETRIC
DISTRIBUTION
MAX. BUG RATING
High 50-80 12-15 3,000-5,000 Type II or III B1-U0-G1
Medium 50-80 12-15 2,000-4,000 Type II or III B1-U0-G1
44
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
COLLECTOR STREET – NON-CONTINUOUS PEDESTRIAN LIGHTING
The figures and tables below provide direction on the appropriate luminaire selection and non-
median lighting layout when designing a collector street with street lighting at intersections and
non-continuous pedestrian lighting. Street luminaires are to be placed at the intersection with
luminaire on half to one mounting height in front of any existing crosswalks. Pedestrian luminaire
should be located to illuminate locations shadowed by trees or at vehicle-pedestrian conflict
points.
Figure 37: Typical Collector Street with Non-Continuous Pedestrian Lighting Plan
Figure 38: : Typical Collector with Non-Continuous Pedestrian Lighting Cross Section
12 TO 1 MOUNTING HEIGHT TO
CENTERLINE OF CROSSWALK
(TYPICAL)
Travel
Lane
℄
Sidewalk &
Park Strip
Travel
Lane
Striped
Median
Street Width
Travel
Lane
Sidewalk &
Park Strip
Travel
Lane
COLLECTOR NON CONT PEDZ:\18060 Salt Lake Street Lighting Master Plan\CAD\Roadway plans for masterplan.dwg, 6/17/2020 9:59:02 AM, DWG To PDF.pc3
12 TO 1 MOUNTING HEIGHT TO
CENTERLINE OF CROSSWALK
(TYPICAL)
Travel
Lane
℄
Sidewalk &
Park Strip
Travel
Lane
Striped
Median
Street Width
Travel
Lane
Sidewalk &
Park Strip
Travel
Lane
COLLECTOR NON CONT PEDZ:\18060 Salt Lake Street Lighting Master Plan\CAD\Roadway plans for masterplan.dwg, 6/17/2020 9:59:02 AM, DWG To PDF.pc3See Intersections and Crosswalks section on page 14 for intersection lighting criteria and
luminaire recommendations.
45
LIGHTING DESIGN PROCESSTABLE 32: RECOMMENDED COLLECTOR PEDESTRIAN LUMINAIRE AND POLE SPACING CRITERIA
PEDESTRIAN
ACTIVITY
POLE SPACING
(FT)
POLE HEIGHT
(FT)LUMEN OUTPUT (LM)
TYPICAL
PHOTOMETRIC
DISTRIBUTION
MAX. BUG RATING
Medium 80-120 12-15 2,500-5,000 Type II or III B1-U2-G1
Low 80-120 12-15 2,500-4,000 Type II or III B1-U0-G1
46
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
COLLECTOR STREET – STREET LIGHTING AT INTERSECTIONS ONLY
The figures and tables below provide direction on the appropriate luminaire selection and non-
median lighting layout when designing a collector street with street lighting at intersections and
non-continuous pedestrian lighting. Street luminaires are to be placed at the intersection with
luminaire on half to one mounting height in front of any existing crosswalks, Figures 39 and 40.
Figure 39: Typical Collector with Street Lighting at Intersections Only Plan
Figure 40: Typical Collector with Street Lighting at Intersections Only Cross Section
See Intersections & Crosswalks Section on page 14 for intersection lighting criteria and
luminaire recommendations.
12 TO 1 MOUNTING HEIGHT TO
CENTERLINE OF CROSSWALK
(TYPICAL)
Travel
Lane
℄
Sidewalk &
Park Strip
Travel
Lane
Striped
Median
Street Width
Travel
Lane
Sidewalk &
Park Strip
Travel
Lane
COLLECTOR STREET INT ONLY
12 TO 1 MOUNTING HEIGHT TO
CENTERLINE OF CROSSWALK
(TYPICAL)
Travel
Lane
℄
Sidewalk &
Park Strip
Travel
Lane
Striped
Median
Street Width
Travel
Lane
Sidewalk &
Park Strip
Travel
Lane
COLLECTOR STREET INT ONLY
47
LIGHTING DESIGN PROCESSLOCAL STREET – CONTINUOUS STREET LIGHTING
Figure 41: Typical Local Continuous Street Lighting Layout
Figure 42: Typical Local Continuous Street Lighting Cross Section
Local Continuous Street Lighting
℄
Parking &
Travel Lane
Sidewalk &
Park Strip
Parking &
Travel Lane
Sidewalk &
Park Strip
Street Width
LOCAL CONT STREET LIGHTING
Local Continuous Street Lighting
℄
Parking &
Travel Lane
Sidewalk &
Park Strip
Parking &
Travel Lane
Sidewalk &
Park Strip
Street Width
LOCAL CONT STREET LIGHTING
48
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
TABLE 33: LOCAL STREET TARGET CRITERIA PER IES RP-8-18
PEDESTRIAN ACTIVITY ROADWAY SIDEWALKS
AVERAGE LUMINANCE (CD/M2)LUMINANCE AVG:MIN RATIO AVERAGE ILLUMINANCE (FC)
High 0.6 6:1 1.0
TABLE 34: RECOMMENDED LOCAL STREET LUMINAIRE CRITERIA
STREET WIDTH
(FT)
PEDESTRIAN
ACTIVITY
POLE SPACING
(FT)
POLE HEIGHT
(FT)LUMEN OUTPUT (LM)
TYPICAL
PHOTOMETRIC
DISTRIBUTION
MAX. BUG RATING
30-50 High
140-180 30 4,500-5,500 Type II or III B1-U0-G1
180-220 30 4,500-7,750 Type II or III B2-U0-G1
50-80 High 120-160 30 4,500-7,000 Type II or III B1-U0-G1
160-200 30 5,500-8,250 Type II or III B2-U0-G1
49
LIGHTING DESIGN PROCESSLOCAL STREET – NON-CONTINUOUS STREET LIGHTING
Figure 43: Typical Local Street with Non-Continuous Street Lighting Plan
Figure 44: Typical Local Street with Non-Continuous Street Lighting Cross Section
Local Non Continuous Street Lighting
℄
Parking &
Travel Lane
Parking &
Travel Lane
Sidewalk &
Park Strip
Sidewalk &
Park Strip
Street Width
LOCAL NON CONT STREET
LIGHTING
Local Non Continuous Street Lighting
℄
Parking &
Travel Lane
Parking &
Travel Lane
Sidewalk &
Park Strip
Sidewalk &
Park Strip
Street Width
LOCAL NON CONT STREET
LIGHTING
TABLE 35: RECOMMENDED LOCAL STREET LUMINAIRE CRITERIA
STREET WIDTH
(FT)
PEDESTRIAN
ACTIVITY
POLE SPACING
(FT)
POLE HEIGHT
(FT)LUMEN OUTPUT (LM)
TYPICAL
PHOTOMETRIC
DISTRIBUTION
MAX. BUG RATING
30-50 High 280-360 30 4,500-5,500 Type II or III B1-U0-G1
360-440 30 4,500-7,750 Type II or III B2-U0-G1
Medium 320-440 30 4,000-5,500 Type II or III B1-U0-G1
50-80 High 240-320 30 4,500-7,000 Type II or III B1-U0-G1
320-400 30 5,500-8,250 Type II or III B2-U0-G2
Medium 300-400 30 4,500-6,000 Type II or III B2-U0-G2
50
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
LOCAL STREET – NON-CONTINUOUS STREET LIGHTING AND CONTINUOUS PEDESTRIAN LIGHTING
Figure 45: Typical Local Street with Non-Continuous Street and Continuous Pedestrian Lighting Plan
Figure 46: Typical Local Street with Non-Continuous Street and Continuous Ped Lighting Cross Section
Local Non Continuous Street Continuous Ped Lighting
℄
Parking &
Travel Lane
Parking &
Travel Lane
Sidewalk &
Park Strip
Sidewalk &
Park Strip
Street Width
Sidewalk &
Park Strip
LOCAL NON CONT STREET CONT
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Local Non Continuous Street Continuous Ped Lighting
℄
Parking &
Travel Lane
Parking &
Travel Lane
Sidewalk &
Park Strip
Sidewalk &
Park Strip
Street Width
Sidewalk &
Park Strip
LOCAL NON CONT STREET CONT
PEDZ:\18060 Salt Lake Street Lighting Master Plan\CAD\Roadway plans for masterplan.dwg, 6/17/2020 9:59:07 AM, DWG To PDF.pc3
51
LIGHTING DESIGN PROCESSTABLE 38: RECOMMENDED LOCAL PEDESTRIAN LUMINAIRE CRITERIA
STREET WIDTH
(FT)
PEDESTRIAN
ACTIVITY
POLE SPACING
(FT)
POLE HEIGHT
(FT)LUMEN OUTPUT (LM)
TYPICAL
PHOTOMETRIC
DISTRIBUTION
MAX. BUG RATING
30-50 High
60-90 12 2,500-4,000 Type II or III B1-U0-G1
90-120 12 4,000-5,500 Type II or III B1-U0-G1
50-80 High 60-90 12 3,500-5,500 Type II or III B1-U0-G1
TABLE 36: LOCAL SIDEWALK TARGET CRITERIA PER IES
RP-8-18
PEDESTRIAN ACTIVITY SIDEWALKS
AVERAGE ILLUMINANCE (FC)
High 1.0
Medium 0.5
TABLE 37: RECOMMENDED LOCAL STREET LUMINAIRE CRITERIA
STREET WIDTH
(FT)
PEDESTRIAN
ACTIVITY
POLE SPACING
(FT)
POLE HEIGHT
(FT)LUMEN OUTPUT (LM)
TYPICAL
PHOTOMETRIC
DISTRIBUTION
MAX. BUG RATING
30-50 High
280-360 30 4,500-5,500 Type II or III B1-U0-G1
360-440 30 4,500-7,750 Type II or III B2-U0-G1
50-80 High 240-320 30 4,500-7,000 Type II or III B1-U0-G1
320-400 30 5,500-8,250 Type II or III B2-U0-G2
52
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
LOCAL STREET –CONTINUOUS PEDESTRIAN LIGHTING
Figure 47: Typical Local Street with Continuous Pedestrian Lighting Plan
Figure 48: Typical Local Street with Continuous Pedestrian Lighting Cross Section
Local Continuous Ped Lighting
36'-0"
℄
Parking &
Travel Lane
Parking &
Travel Lane
Sidewalk &
Park Strip
Sidewalk &
Park Strip
Street Width
LOCAL CONT PEDZ:\18060 Salt Lake Street Lighting Master Plan\CAD\Roadway plans for masterplan.dwg, 6/17/2020 9:59:11 AM, DWG To PDF.pc3
Local Continuous Ped Lighting36'-0"
℄
Parking &
Travel Lane
Parking &
Travel Lane
Sidewalk &
Park Strip
Sidewalk &
Park Strip
Street Width
LOCAL CONT PEDZ:\18060 Salt Lake Street Lighting Master Plan\CAD\Roadway plans for masterplan.dwg, 6/17/2020 9:59:11 AM, DWG To PDF.pc3See Intersections and Crosswalks section on page 14 for intersection lighting criteria and
luminaire recommendations.
53
LIGHTING DESIGN PROCESSTABLE 39: LOCAL SIDEWALK TARGET CRITERIA PER IES
RP-8-18
PEDESTRIAN ACTIVITY SIDEWALKS
AVERAGE ILLUMINANCE (FC)
High 1.0
Medium 0.5
TABLE 40: RECOMMENDED LOCAL PEDESTRIAN LUMINAIRE CRITERIA
STREET WIDTH
(FT)
PEDESTRIAN
ACTIVITY
POLE
SPACING (FT)
POLE HEIGHT
(FT)LUMEN OUTPUT (LM)TYPICAL PHOTOMETRIC
DISTRIBUTION MAX. BUG RATING
30-50
High 60-90 12 2,500-4,000 Type II or III B1-U0-G1
90-120 12 4,000-5,500 Type II or III B1-U0-G1
Medium 60-90 12 2,500-3,500 Type II, III, or IV B1-U0-G1
90-120 12 3,500-5,500 Type II, III, or IV B1-U0-G1
50-80 High 60-90 12 3,500-5,500 Type II or III B1-U0-G1
Medium 60-90 12 4,000-5,550 Type II or III B1-U0-G1
54
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
LOCAL STREET – NON-CONTINUOUS PEDESTRIAN LIGHTING
Figure 49: Typical Local Street with Non-Continuous Pedestrian Lighting Plan
Figure 50: Typical Local Street with Non-Continuous Pedestrian Lighting Cross Section
TABLE 41: RECOMMENDED LOCAL PEDESTRIAN LUMINAIRE CRITERIA
STREET WIDTH
(FT)
PEDESTRIAN
ACTIVITY
POLE
SPACING (FT)
POLE HEIGHT
(FT)LUMEN OUTPUT (LM)TYPICAL PHOTOMETRIC
DISTRIBUTION MAX. BUG RATING
30-50 Medium 120-180 12 2,500-3,500 Type II, III, or IV B1-U0-G1
180-240 12 3,500-5,500 Type II, III, or IV B1-U0-G1
Low 120-240 12 2,000-4,000 Type II, III, or IV B1-U0-G1
50-80 Medium 120-180 12 4,000-5,550 Type II or III B1-U0-G1
Low 160-240 12 2,500-4,000 Type II, III or IV B1-U0-G1
See Intersections and Crosswalks section on page 14 for intersection lighting criteria and
luminaire recommendations.
Local Non Continuous Ped Lighting
℄
Parking &
Travel Lane
Parking &
Travel Lane
Sidewalk &
Park Strip
Sidewalk &
Park Strip
Street Width
LOCAL NON CONT PED
Local Non Continuous Ped Lighting
℄
Parking &
Travel Lane
Parking &
Travel Lane
Sidewalk &
Park Strip
Sidewalk &
Park Strip
Street Width
LOCAL NON CONT PED
55
LIGHTING DESIGN PROCESSLOCAL STREET – INTERSECTION ONLY LIGHTING
Figure 51: Typical Local Street Intersection Only Lighting Plan
Figure 52: Typical Local Street with Intersection Only Lighting Cross Section
See Intersections and Crosswalks section on page 14 for intersection lighting criteria and
luminaire recommendations.
56
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
Figure 53: Uncovered Bus Stop Lighting Layout
BUS STOP LIGHTING
UNCOVERED BUS STOP
Uncovered bus stops should be lit by a street luminaire positioned 1/2 to 1 mounting height from
the bus stop in the direction of oncoming traffic. The illuminance criteria at bus stops are found
in Table 42.
Figure 54: Covered Bus Stop Lighting Section
BUS SHELTERS
Bus Shelters criteria are found in Table 42. Vertical illuminance aids in facial recognition and visible
comfort and is to be measured 5 ft. above the ground. Street luminaires within 100 ft of bus
shelters increase ambient light and visual comfort.
TABLE 42: LOCAL SIDEWALK TARGET CRITERIA PER IES RP-8-18
BUS STOP CRITERIA HORIZONTAL ILLUMINANCE (FC) VERTICAL ILLUMINANCE (FC)
Uncovered Bus Stop 1.0 0.2
Covered Bus Stop 1.0 1.0
57
LIGHTING DESIGN PROCESSMINIMAL IMPROVEMENTS
CONFIRM EXISTING CONDITIONS
Current existing conditions where improvements are being made should be evaluated prior to
beginning lighting improvement design. One-for-one replacements should be done where the
existing lighting strategy meets the required lighting strategy in the Lighting Warrants Table 1-3. If
the existing lighting strategy is appropriate, the spacing of the existing lights should be upgraded
to meet the lumen requirements for the specific type and land use and the necessary infrastructure,
such as wiring, foundation, and poles are all in good condition. If the lighting strategy in the area
requires additional street or pedestrian lights, supplemental improvements will need to be made.
Supplemental improvements may also need to be made if the spacing is not met or there are
infrastructure issues.
SUPPLEMENTAL IMPROVEMENTS
Supplemental improvements entail adding a limited quantity of new street or pedestrian light
locations to the existing lighting system to illuminate any dark areas on the street. If any of
the following conditions exist, then the improvement area should follow the comprehensive
improvement methodology:
• The existing lighting on the block does not meet the lighting strategy in Tables 1-3: Lighting
Warrants and additional pedestrian or streetlights are necessary to comply with the appropriate
lighting strategy.
• Existing street or pedestrian light spacing exceeds two times the recommended value based
on lighting strategy.
• Lighting only exists on one side of the street and does not sufficiently light the whole street.
To maintain consistency in the lighting design, all luminaires used in supplemental improvements
should match the luminaires chosen for 1-for-1 replacements.
ONE-FOR-ONE REPLACEMENT
Salt Lake City is upgrading existing HID lights to new energy efficient LEDs. The new replacement
lights should meet the lighting criteria set forth in the Luminaire Criteria Tables based on street
classification, adjacent land use and pedestrian conflict. The City is also working to upgrade any
previously installed LEDs that are not within the luminaire specification and are causing obtrusive
glare and light trespass to a luminaire that is more appropriate to the specific location. All one-
for-one replacements should match the appreciate color temperature based on adjacent land use
and existing LEDs that do not meet the appropriate CCT should be considered for replacement.
58
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
As part of the lighting upgrades throughout the city, the new LED lights will be compatible with
a city-wide wireless lighting control system. This lighting control system will allow Salt Lake City
to have precise control over each individual light throughout the City, enabling the City to raise or
lower light levels when needed or desired. Dimming strategies will vary throughout the City based
on adjacent land use, pedestrian conflicts, and time of day to ensure vehicle and pedestrian safety
while working to minimize light pollution and light trespass.
When dimming lighting in a certain area, the lighting strategy must be considered, speed limit on the
streets, and vehicle and pedestrian volumes.
• When dimming continuous street or pedestrian lighting, the first strategy is to dim from high
or medium pedestrian criteria to medium or low pedestrian criteria. If continuous lighting
is already in a low pedestrian area, research supports that when using broad spectrum LED
sources, dimming to 70% of current output or lower can still provide sufficient lighting. If the
City is interested in dimming below a low pedestrian criteria for a certain continuously lighted
street, the City should undergo a public engagement pilot study with residents, city council,
police, fire, and the city attorney to further understand the implications of reduced lighting in
the area.
• Along streets with non-continuous street and pedestrian lighting, there is not a required
lighting criteria and lights should be dimmed to comfortable levels while still maintaining the
desired effect of the lighting design.
DIMMING IN RESIDENTIAL AREAS:
All street classifications are found in all single-and multi-family residential areas in Salt Lake City.
The Table below summarizes the recommended dimming strategies based on street classification,
and pedestrian conflict.
TABLE 43: RECOMMENDED DIMMING STRATEGIES FOR RESIDENTIAL AREAS
ARTERIAL STREET COLLECTOR STREET LOCAL STREET
Multifamily Residential
(Med Ped Conflict)
Dim Street and
Pedestrian Lights to
Low Ped Conflict
Dim Street and
Pedestrian Lights to
Low Ped Conflict
Dim Street and
Pedestrian Lights to Low
Ped Conflict
Single Family Residential
(Low Ped Conflict)
*Dim Street and
Pedestrian Lights to
Comfortable Light
Levels
*Dim Street and
Pedestrian Lights to
Comfortable Light
Levels
*Dim Street and
Pedestrian Lights to
Comfortable Light Levels
* Dimming to comfortable light levels below the Low Pedestrian Criteria requires a public engagement
process.
LIGHTING CONTROLS AND ADAPTIVE DIMMING STRATEGIES
59
LIGHTING DESIGN PROCESSDIMMING IN DOWNTOWN RESTAURANT/RETAIL ENVIRONMENTS
It is essential to maintain proper light levels based on pedestrian conflict when adjusting light
levels in the downtown. Pedestrian traffic fluctuates based on the night of the week, as well as the
time of day. If an event is happening within a public gathering space or venue, higher pedestrian
volume should be expected, and the recommended dimming strategy should be overruled and
the areas surrounding the event center should be lighted to criteria. The table below shows the
dimming strategies based on night of the week and time of night.
TABLE 44: RECOMMENDED DIMMING STRATEGIES FOR DOWNTOWN
DIMMING STRATEGY
Sunday Night - Wednesday
Night
Dusk to 10PM Light to Criteria
10PM to Midnight Reduce Criteria to a Lower Pedestrian Conflict
Midnight to 2:30AM Reduce Criteria to Low Pedestrian Conflict or
to Comfortable Light Levels
2:30AM to Dawn Reduce Criteria to Low Pedestrian Conflict or
to Comfortable Light Levels
Thursday Night - Saturday
Night
Dusk to 10PM Light to Criteria
10PM to Midnight Reduce Criteria to a Lower Pedestrian Conflict
Midnight to 2:30AM Light to Criteria
2:30AM to Dawn Reduce Criteria to Low Pedestrian Conflict or
to Comfortable Light Levels
* Dimming to comfortable light levels below the Low Pedestrian Criteria requires a public engagement
process
DIMMING INTERSECTION AND MID-BLOCK CROSSINGS
Intersections and mid-block crossing should be dimmed separately from the rest of the streetlights;
however, the same strategy should be used. If the intersection or crossing has less traffic at certain
times throughout the night, the criteria can be reduced to a lower pedestrian conflict criteria. If
further reduction in light levels are desired, a similar public engagement process should be done
to ensure the safety of pedestrians and vehicles at intersection and mid-block crossings.
60
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
LUMINAIRE SPECIFICATIONS
Luminaire specifications are found in Tables 55 & 56
TABLE 55: SPECIFICATION OVERVIEW
CONTROLS ELECTRICAL SYSTEM
Integral 0-10V dimmable drivers to adjust light
levels. All streetlights will be installed with an ANSI
7 pin photocell receptacle to be compatible with
wireless controls in the future.
Single phase 120/240V electrical system
voltage.
LIGHT STANDARD SPECIFICATION LIGHT STANDARD FOUNDATIONS
The light standard - also referred to as the pole -
should be tapered, round galvanized steel with a
12-inch bolt circle. Color match the head and arm of
the pole. Design replacement poles, heads, and/or
arms to match existing color and type of adjacent
poles if appropriate and with written City approval.
City approval of decorative or non-standard poles
is required. Painted over galvanized is required for
any pole requiring color change. All new mast arm
installations are required to be 2, 6, or 10 feet. The
City must approve all poles with banner arms and
power receptacles.
City standard design for all precast concrete
or poured-in-place light standard foundations.
While the City accepts poured-in-place
foundations, precast concrete foundations are
preferred and should be installed whenever
possible.
61
LIGHTING DESIGN PROCESSTABLE 56: LUMINAIRE SPECIFICATIONS
Correlated Color Temperature
(CCT)3000K Maximum
Color Rendering Index (CRI)≥65 in most areas, or > 40 in Critical Wildlife Habitat
Luminaire Lumen Range
The lumen output should comply with the lumen range specified in the
Recommended Luminaire Criteria Tables based on street classification,
adjacent land use and pedestrian conflict. Criteria for luminaire CCT are
found in Volume 1 Table 5.
Luminaire Finish
Die cast aluminum housing with fade and abrasion resistant polyester
powder coat finish. Finish should match existing color of luminaires along
street.
Luminaire Warranty 10 years on luminaire and components.
Luminaire Warranty Period Earliest warranty period allowed starts on the date of receipt by City.
Luminaire Identification Luminaire external label per ANSI C136.15, and an interior label per ANSI
C136.22 required.
Operation and Storage
Temperature '-40°C to +40°C.
Frequency Vibration 'Luminaire should withstand low and high frequency vibration, per ANSI
C136.31, over the rated life of the light source.
Minimum Rated Life 70,000 hours minimum at 55°C, per IES TM-21
IP rating IP65 or greater.
Voltage 120/277.
Control Dimmable and installed with ANSI 7 pin photo receptacle to be compatible
with wireless luminaires controls in the future.
Cooling System Passive utilizing heat sinks, convection, or conduction. Upper surfaces
required to shed precipitation. Cooling fans are not allowed.
Photocontrol Individual multi-contact 7-pin twist lock receptacle per ANSI C136.41. Or
control module.
Electrical Immunity
Luminaire are required to meet the performance requirements specified
in ANSI C136.2 for dielectric withstand, using the DC test level and
configuration.LUMINAIREPower Factor (PF)Minimum of 0.9 at full input power.
Total Harmonic Distortion (THD)Maximum of 20 percent at full input power.
Restriction of Hazardous
Substances (RoHS)Restriction of Hazardous Substances (RoHS) compliant drivers required.
Surge Protection
Protection from all electrical surges with an elevated electrical immunity
rating, including but not limited to lightning strikes and stray current in rebar
and concrete required for all LEDs. Integral surge protection to the LED
power supply required.
“Elevated” (10kV/10kA) requirements per IEEE/ANSI C62.41.2 for luminaire.
Manufacturer indication of failure of the electrical immunity system can
possibly result in disconnect of power to luminaire required.
Total Power Consumed in Off
State Maximum 8 watt off-state power consumption for luminaire, including driver.
Electromagnetic interference
Electromagnetic interference: Compliance with Federal Communications
Commission (FCC) 47 Code of Federal Regulations (CFR) part 15 non-
consumer radio frequency interference (RFI) and/or electromagnetic
interference (EMI) standards.LED DRIVERS
62
LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
LIGHTING CALCULATIONS
PURPOSE
Lighting design calculations for new installations is an iterative process. The use of lighting models
to calculate the luminance along streets and illuminance on sidewalks is the most efficient and
accurate way to design to criteria. Light trespass calculations should also be included to limit the
amount of obtrusive light in the City. This section describes the required calculations to ensure
that all criteria is met for all new installations.
HOW TO SET UP A CALCULATION
The following sections document the parameters and considerations when calculating street
lighting levels.
IES FILES
The first step in running a calculation is to find and download the photometric in IES file format
for the specific luminaire being considered. This file is available on the manufacturer’s website and
can be downloaded into any lighting calculation simulation software. The IES file will contain all
information for the luminaire, such as lumen output, color temperature, wattage, distribution, and
voltage.
LIGHT LOSS FACTOR FOR LED
A light loss factor should be applied to every luminaire considered, to ensure that the maintained
light levels will meet the target criteria. Table 57, below, lists typical light loss factors for LEDs and
legacy products found throughout Salt Lake City.
TABLE 57: TYPICAL LIGHT LOSS FACTORS
LIGHT SOURCE LUMINAIRE DIRT DEPRECIATION
(LDD)
LUMINAIRE LUMEN
DEPRECIATION (LLD)
TOTAL LIGHT LOSS FACTOR
(LLF)
LED 0.9 0.97 0.818
HPS 0.9 0.9 0.81
MH 0.9 0.7 0.63
HPS: High Pressure Sodium
MH: Metal Halide
7 Use 0.9 or LM value provided by the Manufacturer at 60,000 hours, if L70 is greater than 100,000 hours
8 If using an LM value provided by the Manufacturer, the Total LLF is equal to 0.9 x LM60,000hr
63
LIGHTING DESIGN PROCESSLUMINANCE AND ILLUMINANCE CALCULATIONS
Calculations should be done in AGi32, DIALux, Visual, or comparable software, and include the
following calculation grids:
• ROADWAY LUMINANCE
- A calculation grid is required for every lane of traffic and oriented in the direction of travel
spaced 10’ OC along each lane, with two points across each lane.
- Every section of roadway where criteria changes requires a separate calculation grid.
• INTERSECTION ILLUMINANCE
- Intersection calculations done using horizontal illuminance grids that include the whole
intersection, as well as all crosswalks associated with the intersections. Calculation points
placed in a 5’x5’ grid.
• SIDEWALK ILLUMINANCE
- Horizontal sidewalk illuminance grids placed on all sidewalks, spaced every 5’-10’ OC along
the sidewalk with two points across the sidewalk.
• LIGHT TRESPASS ILLUMINANCE
- Light trespass grids located 5’ past the edge of ROW, into private property. Light trespass
grids placed 5’ AFF, oriented toward the street with calculation points every 5’-10’ OC.
- Light trespass calculation grids separated based on adjacent land use. If the project goes from
a residential area to a commercial area, a separate light trespass calculation grid required for
each section of the project.
- If a structure is within 5’ from the property line, light trespass grid to be placed on the
structure, 5’ AFF.
- Light trespass values should not exceed the following:
• Single Family Residential, Multifamily Residential, Industrial and Open Space properties:
0.1FC MAXIMUM.
- If this criteria is not feasible with proper shielding and distribution, a variance
may be considered to allow up to 0.2Fc Maximum light trespass in residential
areas. Designer will be required to submit a narrative describing the efforts to
control light trespass to the City Engineer.
• Commercial, Restaurant/Retail/Civic, and Mixed-use Residential properties: 0.3FC
MAXIMUM
• CROSSWALK VERTICAL ILLUMINANCE
- Vertical illuminance grids are required in all crosswalks at 5’ AFF, and oriented toward
oncoming traffic (See Figure 55). Calculation points should be located along the center line
of each crosswalk, placed every 5’ OC.
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LIGHTING DESIGN PROCESSSALT LAKE CITY STREET LIGHTING MASTER PLAN // VOLUME 2
Designers submissions to the City should include a calculation summary table for each calculation
grid and include the average illuminance or luminance, maximum illuminance or luminance,
minimum illuminance or luminance, and Avg:Min ratio. Calculated values may vary from criteria by
no more than 10% above or below.
Figure 55: Horizontal Intersection Illuminance Grid
Figure 56: Vertical Intersection Illuminance Grid
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LIGHTING DESIGN PROCESSFigure 57: Roadway, Sidewalk, and Light Trespass Calculation Grid Setup
International Dark-Sky Association
5049 E. Broadway Blvd., #105,
Tucson, AZ 85711 USA
tel +1.520.293.3198
www.darksky.org
Executive Director: Ruskin Hartley
Emeritus Director: David L. Crawford, Ph.D.
Board of Directors: Diane Knutson, President, USA • Kellie Pendoley, Vice President, Australia • Kim Patten, Treasurer, USA • Ken Kattner, Secretary, USA •
Laurel Alyn-Forest, USA • Alejandro Sanchez Miguel, Spain
August 16, 2021
Amy Fowler, Chair
Salt Lake City Council
PO Box 145476
Salt Lake City, UT 84114-5476
Re: Street Lighting Master Plan
Dear Chair Fowler and Councilmembers:
The International Dark-Sky Association (IDA) is the recognized authority on light pollution and is
the leading organization combating light pollution worldwide. We advocate for a future in which
the night sky, filled with stars, is celebrated and protected around the world as shared heritage
benefitting all living things. Protecting nighttime darkness and promoting quality outdoor lighting
practices have distinct benefits for wildlife, human health and wellbeing, energy security, and pub-
lic safety.
Our vision is encapsulated in Values-Centered Outdoor Lighting (https://www.darksky.org/our-
work/lighting/values-centered-outdoor-lighting/), a resolution adopted by our Board of Directors in
January 2021. These values are in turn described by the Five Principles for Responsible Outdoor
Lighting (https://www.darksky.org/our-work/lighting/lighting-principles/) jointly promoted by IDA
and the Illuminating Engineering Society (IES):
1. All light should have a clear purpose
2. Light should be directed only where needed
3. Light should be no brighter than necessary
4. Light should be used only when it is useful
5. Use warmer color lights whenever possible
IDA supports the draft Street Lighting Master Plan that currently under consideration by the Salt
Lake City Council. We find it to be consistent with both Values-Centered Outdoor Lighting and the
Five Principles. It contains the best practices that we encourage for all jurisdictions, and if adopted
it would set a new standard for street lighting plans for large cities.
In particular, the IDA commends specific policy elements of the plan that give it flexibility while not
compromising on core principles. These elements include:
• A flexible approach to allow illumination levels below IES recommendations that en-
courages dimming strategies based on community engagement and that benefits
both dark skies and wildlife (Principles 3 and 4).
• Use of zones for maximum permissible Correlated Color Temperature (CCT) values
that limit 3000 kelvin (K) lighting to commercial zones; sets 2700 K as the maximum
for residential zones without commercial elements; and establishes 2200 K as a
maximum in open space and the industrial zones, which happen to be near sensitive
natural resources in and near the city (Principle 5).
• Inclusion of policy goals to minimize impacts on wildlife and to balance energy effi-
ciency with human and environmental health needs (Principle 1).
• A commitment to shielding decorative street lighting to eliminate uplight (Principles 1
and 2).
• Specific commitment to reduce the obtrusive effects of light at night, including light
trespass onto private property, light pollution affecting the region, and glare that re-
duces visibility and nighttime safety and comfort (Principle 2).
Municipal lighting systems represent a large component of the light pollution generated by cities in
the United States. This plan, when implemented, will reduce light pollution from Salt Lake City and
make it a leader in this field.
We have experience with the successful LED streetlight conversion of Tucson, Arizona, that
measurably decreased the city’s light emissions (see https://www.sciencedirect.com/science/arti-
cle/abs/pii/S0022407317308178). Appropriate technology and lighting design approaches are
available to upgrade street lighting systems, reduce energy consumption, and limit the adverse
impacts of excessive artificial light at night. The Salt Lake City plan goes a step further to incorpo-
rate 2200 K lighting in some areas, and offers flexibility to choose lower CCTs in residential and
commercial areas. This plan would put Salt Lake City at the vanguard of outdoor lighting best
practices among world municipalities.
Given the above considerations, we urge the City to adopt the Street Lighting Master Plan.
Yours sincerely,
John C. Barentine, Ph.D.
Director of Conservation
cc: Salt Lake City Council
Hon. Erin Mendenhall, Mayor