Dark Sky Friendly Lighting in Flagstaff: A Case Study

Flagstaff’s Dark Sky Friendly History

Flagstaff, Arizona is a small city located in Coconino County in northern Arizona. The picturesque location is known for its high elevation, mountainous views, and cold air. The city was officially incorporated in the year 1882. Flagstaff is known for its famous observatory, Lowell Observatory, which was built in 1894 and named after the Lowell family of Boston, Massachusetts. Since its creation, the Lowell observatory has been home to many famous astronomical discoveries such as the first-ever sighting of dwarf planet Pluto.

In 1958, Flagstaff enacted the world’s first lighting ordinances that focused on limiting searchlights. Continuing this trend, Flagstaff announced new lighting codes in 1989 which restricted the amount of permissible outdoor light per acre in the city itself and in greater Coconino County.  

When 2001 arrived, Flagstaff became the first city in America to be recognized as a dark sky friendly city by the International Dark Sky Association.

Current Flagstaff Lighting Regulations

Flagstaff, Arizona currently releases a new report every year on how well the community has held up its goals to be completely dark sky friendly. The report can be accessed through the International Dark Sky Association’s website and provides an in-depth look at how dark sky lighting has impacted the community.

Generally, the kind of outdoor lights that Flagstaff classifies as acceptable are low pressure sodium and 590 nanometer amber LEDs. Amber LED fixtures are also used for turtle and wildlife friendly lighting and can be purchased on our website in various fixture styles. Outdoor lights in Flagstaff generally also must be fully shielded, which means minimal backlight and no uplight.

In addition, Flagstaff categorizes uses for lighting into three classes. Class 1 represents areas where the most light is needed and Class 3 represents areas where lighting is strictly decorative such as at the base of a flagpole. 

 As of 2020, Flagstaff’s lighting regulations consist of a map of three zones, which can be seen to the right. Zone 1 has the most stringent lighting regulations and Zone 3, while still remaining dark sky friendly, permits some leeway in terms of shielding and lumen output. 

Flagstaff has done a great job preserving the clarity of the night sky with its dark sky friendly lighting policies over the years. Additionally, noncompliance with these regulations carries a misdemeanor fine, providing residents even more incentive to follow the rules. By keeping the sky clear and dark, the natural beauty of the mountains is visible and astronomers can keep making incredible discoveries without human light pollution blocking the view.