ADOT completes ‘Dark Skies’ LED lighting project in Flagstaff

FLAGSTAFF – The Arizona Department of Transportation has completed installation of amber LED highway lights in the Flagstaff area in support of both roadway safety and the city’s internationally recognized commitment to dark skies.

The project, which started in May, allowed crews to install amber LED lights that replace more than 370 outdated high pressure sodium light fixtures used to illuminate highways under ADOT’s jurisdiction in the Flagstaff area. 

The project’s goal is to effectively reduce impacts on the brightness of the night sky in Flagstaff, which is recognized as the world’s first international Dark Sky City. Crews finished their work last week (June 15-19).

“All the planning and testing have become a reality with the completion of our installation work,” said ADOT Northcentral District Administrator Jeremy DeGeyter. “I want to emphasize the importance of the partnership we’ve had with the local community, including Flagstaff and dark skies supporters.”

The $1.1 million amber LED project struck a balance between highway safety, especially with pedestrians and cyclists in mind, while also supporting dark skies and astronomy in the area. Flagstaff is home to Lowell Observatory and the U.S. Naval Observatory. Last year, the city received the Dark Sky Place of the Year award from DarkSky International.

ADOT has switched to amber LED lighting at all I-17 and I-40 interchanges in Flagstaff, including the large interchange connecting the two interstates. Lighting also has been converted to amber LED along stretches of Milton Road and Route 66 (Santa Fe Boulevard) near and in the downtown Flagstaff area.

“In the year of Flagstaff’s 25th anniversary as the world’s first international Dark Sky City, it is fitting that we have another achievement to celebrate–the nation’s first deployment of amber LEDs on interstate highways,” said Dr. Danielle Adams, executive director of the Flagstaff Dark Skies Coalition (FDSC). “Through the collaborative efforts of ADOT, the city of Flagstaff, Coconino County, the U.S. Naval Observatory Flagstaff Station and FDSC, we have again pioneered a new standard for protecting urban night skies.”

For decades ADOT has used fixtures and shields in Flagstaff and elsewhere to limit the upward projection of highway lighting.

More information about ADOT’s roadway lighting project is available at azdot.gov/FlagstaffLightingProject. 

Real-time highway conditions are available on ADOT’s Arizona Traveler Information site at AZ511.gov, the az511 app (download for Apple or Android devices) or by calling 511.