Inyo County, CA Outdoor Lighting: Light Trespass (2026)

Light trespass - light spilling from one property onto a neighbor's - is addressed directly in Inyo County's Outdoor Lighting ordinance, codified as Title 18 Chapter 18.74. The County's General Plan Control of Light and Glare policy provides the underlying authority, and the adopted chapter implements it with operational standards. As reported in Sierra Wave's coverage of the ordinance, outdoor lighting must be installed to prevent glare, light trespass, and light pollution. The shielding standards work to limit spill: unshielded fixtures are limited to 100 lumens, while fixtures up to a maximum 600 lumens must be partially or totally shielded and fitted with an opaque top so light is directed downward rather than outward onto adjacent properties. Existing nonconforming fixtures generally need not be altered, but the County retains authority to require a light that causes problems to be shielded, filtered, redirected, or replaced - the core enforcement tool against light trespass. Flag lighting is also constrained: U.S. and California flags must be taken down at night or illuminated only within the area of the flag, without light trespass. Because the precise enforcement thresholds and any measured illuminance limits are set in the adopted Chapter 18.74, neighbors experiencing light spill should document the source and contact the Inyo County Planning Department, which administers the lighting standards and can require corrective shielding or redirection.