Dark Sky Rules: Anza vs Palm Springs

Riverside County Ordinance 655, the Mount Palomar Light Pollution Ordinance, imposes some of the strictest outdoor-lighting rules in California. Within approximately 45 miles of Palomar Observatory (Zones A and B) all new exterior lighting must be shielded, low-pressure or filtered low-color-temperature sodium, and most decorative lighting must be extinguished after 11 p.m.

Palm Springs has one of California's strongest dark-sky outdoor lighting ordinances under PSMC Chapter 93.21. All outdoor fixtures must be fully shielded with cutoff optics, use 3000K or lower color temperature LEDs, meet strict lumen caps per property, and avoid light trespass. The goal is to preserve views of Mt. San Jacinto, protect wildlife, and maintain the starry desert sky.