Discussion:  Street Lighting to Enhance Dark Skies (SLEDS) Status Update

The SLEDS Project’s primary objective is to find a solution to Flagstaff’s current street lighting predicament while balancing dark skies, safety and maintenance/cost effectiveness objectives.
 
The SLEDS Project is the result of several years of discussions between the City and the local observatories (USNOFS and Lowell Observatory) that started in May 2012.  At that time, the City found itself in a lighting predicament as Low Pressure Sodium (LPS), the preferred lighting source since 1989, was becoming increasingly more expensive to purchase, quality replacement parts were becoming more difficult to acquire and we were experiencing structural failures of the pole/mast arm connection due to the size and weight of the LPS fixture, especially in wind prone areas. 
 
In June 2015, Council approved an Inter-Governmental Agreement (IGA) with ADOT to secure funding for the SLEDS Project.  This was in the form of $100K (FY16) to hire a Consultant Team (ultimately Monrad Engineering), $200K (FY16) for test fixtures to support the Consultant Team’s work, and $256K (FY18) for the first phase of lighting replacements, all of the funding coming from the Flagstaff Metropolitan Planning Organization’s (FMPO) Surface Transportation Program (STP).
 
The June 2015 Staff Summary Report concluded with “This SLEDS Project is an opportunity for Flagstaff to demonstrate to other municipalities an innovative lighting solution for dark sky preservation with Light Emitting Diode (LED) technology that achieves municipal objectives for safety and cost effectiveness and astronomical objectives for maintaining dark skies.”  That description is, of course, a partial and generalized list of priorities that the SLEDS Team is balancing.
 
The subsequent Request for Proposals (RFP) utilized to procure the best qualified Consultant Team has similar language to the Staff Summary Report:
 
“The City seeks cost effective replacement technologies that (1) maintain or approximate current lighting levels and (2) do not adversely impact the City’s dark sky natural resource or the missions of the Lowell Observatory and the U.S. Naval Observatory.  In consideration of cost effectiveness, the City seeks to utilize existing light pole infrastructure." 

"Measures of Effectiveness may include:

• Light uniformity
• (1) Brightness and (2) spectrum analysis from several perspectives including:
  • On the street
  • At the observatories
  • General sky brightness
  • Identification of ambient light levels (i.e. absence of streetlights)
• Color rendition
• Wind loading (Effective Projected Area)
• Public commentary on lighting levels and color rendition
• Life cycle costs including, but not limited to, initial capital expense, energy use, and maintenance” 

In September 2015, the Consultant Team, led by Monrad Engineering, was awarded a one year and $100K contract to conduct applied research in order to develop a replacement strategy for the City’s increasingly obsolete LPS street lights with newer technology (LED).  This contract has been modified to extend to March 2018 for a 30 month total duration and extended by $41K to a total of $141K.

PROJECT UPDATE:

The SLEDS Team has worked through several tasks to date:

• An assessment of the viability of continuing to use LPS
• A structural analysis of existing light pole/mast arm assembly and retrofit recommendation for existing poles/masts
• Pre-installation observations and measurements of “sky glow” of the Cheshire test area have been completed through ground, aerial and satellite measuring techniques
• Pre-test installation measurements of several Arterial and Major Collector corridors have been obtained to help in determining final locations for Test Fixtures.
• Test fixture recommendations divided into two categories
  • Arterials and selected Major Collectors
  • Selected Major Collectors, Minor Collectors and Local Roads
• Developed specifications for the Minor Collector / Residential Narrow Band Amber Light Emitting Diode (NBALED) test fixtures, Arterial Hybrid Light Emitting Diode (HLED) 80% NBALED/20% 2700K LED test fixtures and Arterial Narrow Band Amber Light Emitting Diode (NBALED) fixtures.

 
SLEDS Project items that are currently in progress:

• Working with Arizona Department of Transportation on SLEDS test fixture procurement
• Draft SLEDS Report  

SLEDS Project next steps:

• Finalize procurement with ADOT
• Installation of test fixtures
  • Arterial and select Major Collectors - NBALED @ 12k lumens
    • Butler Avenue - Milton to Sawmill
    • Fourth Street - Route 66 to Industrial
  • Arterial and select Major Collectors - Hybrid LED @ 9k lumens
    • Butler Avenue - Sawmill to Ponderosa Parkway
    • Route 66 - Arrowhead to Fourth
    • Cedar at West signalized intersection
  • Residential Minor Collectors and Local Streets - NBALED @ 1500 lumens and 2500 lumens
    • Southern half of Cheshire
• Solicit public feedback on the test installations
• Field measurements of test installations

SLEDS project Final Steps:

• SLEDS Team meetings to discuss results of the test areas and begin developing proposed new City Engineering Standards for Street Lighting for eventual Council Adoption
• Establish City Wide replacement scenarios
  • Evaluate Life cycle costs for Alternatives including:
    • Initial capital expense
    • Energy use
    • Maintenance
  • Evaluate citywide lumen output for Alternatives
• Finalize SLEDS Project Report
• City Council Work Session/Regular Meeting to discuss SLEDS Team recommendations and consideration of Engineering Standards adoption.

COUNCIL GOALS:

TRANSPORTATION AND OTHER PUBLIC INFRASTRUCTURE
Deliver quality community assets and continue to advocate and implement a highly performing multi-modal transportation system.

 ENVIRONMENTAL AND NATURAL RESOURCES
Actively manage and protect all environmental and natural resources.



REGIONAL PLAN:

Goal T.2. Improve transportation safety and efficiency for all modes.

                Policy T.2.1. Design infrastructure to provide safe and efficient movement of vehicles, bicycles, and pedestrians.

                Policy T.2.2. Consider new technologies in new and retrofitted transportation infrastructure.

                Policy T.2.3. Provide safety programs and infrastructure to protect the most vulnerable travelers, including the young, elderly, mobility impaired, pedestrians, and bicyclists.

Goal T.3. Provide transportation infrastructure that is conducive to conservation, preservation, and development goals to avoid, minimize, or mitigate impacts on the natural and built environment.
 

Policy T.3.6. Seek to minimize the noise, vibration, dust, and light impacts of transportation projects on nearby land uses.

Goal T.4. Promote transportation infrastructure and services that enhance the quality of life of the communities within the region.

Goal T.5. Increase the availability and use of pedestrian infrastructure, including FUTS, as a critical element of a safe and livable community.

                Policy T.5.2. Improve pedestrian visibility and safety and raise awareness of the benefits of walking

Goal T.6. Provide for bicycling as a safe and efficient means of transportation and recreation.

Goal E&C.5. Preserve dark skies as an unspoiled natural resource, basis for an important economic sector, and core element of community character.

                Policy E&C.5.1. Evaluate the impacts of the retention of dark skies regarding lighting infrastructure and regulatory changes, land use decisions or changes, and proposed transportation developments within the region.

                Policy E&C.5.2. Encourage and incentivize voluntary reduction of “exempt” lighting that degrades night sky visibility, and work to prevent light trespass whenever possible in both public and private areas.

Goal LU.19. Develop a manageable evolution of the main corridors into contextual place makers.

                Policy LU.19.4. Balance automobile use, parking, bicycle access, while prioritizing pedestrian safety along all corridors.