Mariposa County, CA Outdoor Lighting: Dark Sky Rules (2026)

As of this writing, the adopted Mariposa County zoning code (Title 17, Chapter 17.108 Supplementary Standards) regulates structure location, height, parking, and signs, but does not include a standalone dark-sky or outdoor-lighting chapter. The County is updating its Development Code, and the September 2024 draft Article 3 adds Section 17.46 'Outdoor Light and Glare.' Under the draft, exterior lighting standards would include: light fixtures limited to a maximum of 250 watts; exterior floodlights not projecting above 20 degrees below the horizontal plane; security and structure-mounted lighting using 'full cutoff fixtures with the light source fully shielded' that 'shall not direct light into the sky, adjacent properties, public easements, or rights-of-way'; a prohibition on blinking, flashing, high-intensity, or bright lights; and lighting plans required for projects subject to design or discretionary review. Outdoor display-area lighting would have to be 'turned off within thirty (30) minutes after closing of the business.' Holiday and temporary lighting, and code-required lighting, would be exempt. These provisions reflect the County's interest in preserving the dark night skies of the rural Sierra and Yosemite region, but because they are still a draft, they are not yet enforceable. California has no statewide residential dark-sky mandate, so until the update is adopted, outdoor lighting is primarily addressed through nuisance and design-review review.