Merced, CA Outdoor Lighting: Dark Sky Rules (2026)

The City of Merced does not have a stand-alone outdoor-lighting or 'dark-sky' chapter in its Zoning Ordinance; lighting is addressed in piecemeal fashion, most concretely through the sign-illumination standards of Section 20.62.160 (Ord. No. 2549, 2023). That section requires that the illumination of signs, from internal or external sources, be designed to avoid negative impacts on surrounding rights-of-way and properties, that light sources be shielded from adjacent buildings and streets, and that lighting not create excessive glare for pedestrians or motorists. Among its dark-sky-oriented provisions: low-pressure sodium is the 'preferred light source to minimize undesirable light in the night sky'; high-pressure sodium, metal halide, fluorescent, quartz, LED, and incandescent sources must be fully shielded; and mercury-vapor light sources are prohibited. Sign illumination is capped at 465 lumens per square foot (5,000 nits) during daylight and 47 lumens per square foot (500 nits) from dusk to dawn. Signs in residential zones may only be indirectly illuminated by a concealed source, may not remain illuminated between 11 p.m. and 6 a.m., and may not flash. General glare control also appears in development standards such as Section 20.46.030 for multi-family projects. For broader area or building lighting beyond signs, the City relies on building-permit review and California's Title 24 energy code rather than a local dark-sky ordinance. Property owners seeking specific exterior-lighting requirements should confirm current standards with Merced Development Services.