Dark Sky Rules: San Ramon vs Walnut Creek

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).

Walnut Creek regulates outdoor lighting through its zoning code to minimize light pollution and glare on neighboring properties. While not a formal Dark Sky community, the city requires shielded fixtures for commercial properties and limits lighting intensity and hours.