Dark Sky Rules: Brentwood vs San Ramon

Brentwood's zoning and development standards include outdoor lighting requirements aimed at minimizing light pollution and glare into neighboring properties and the night sky. Fixtures on new development must generally be full-cutoff or shielded, and light trespass onto adjacent residential lots is limited.

San Ramon regulates outdoor lighting through its Development Code (Title D) to reduce light pollution, glare, and spillover onto adjacent properties. Requirements include shielded fixtures, downward-directed light, and limits on lumens and color temperature (typically 3000K or below preferred). The city is not a formal IDA Dark Sky community but incorporates dark-sky principles in design review for new development, especially near open space preserves (Bishop Ranch Regional Preserve, Las Trampas).