Rocklin, CA Outdoor Lighting: Light Trespass (2026)

Light trespass - light from one property spilling onto a neighboring property - is addressed in unincorporated Placer County mainly through the goal of minimizing light pollution and glare on adjacent parcels. The county's stated policy is to discourage the use of outdoor lighting that shines unnecessarily onto adjacent properties or into the night sky. The clearest enforceable standard is in the Lake Tahoe portion of the county: under the Placer County Tahoe Basin Area Plan lighting standards, all lighting fixtures must be fully shielded and directed downward so as not to produce obtrusive glare onto the public right-of-way or adjoining properties, and parking-lot, walkway and building lights must be directed downward at an appropriate mounting height. These provisions directly limit light trespass onto neighbors in the Tahoe Basin and are enforced together with the Tahoe Regional Planning Agency. Outside the Tahoe Basin, the unincorporated county controls light trespass through the Zoning Ordinance's general design and development standards and through conditions of approval placed on discretionary projects (such as commercial sites and subdivisions), which commonly require shielding, downward direction and limits on light reaching property lines. Persistent residential glare that interferes with a neighbor's use of their property may also be addressed as a nuisance. Property owners experiencing or causing light trespass should contact Placer County CDRA, and Tahoe Basin owners should consult the Area Plan and TRPA.