Riverside County, CA Outdoor Lighting: Billboard Lighting (2026)

Subsection B.13 of the outdoor advertising display standards governs illumination directly: a billboard may be lit unless the permit says otherwise, but the light source itself, the bulb, tube or filament, has to stay hidden behind the display face rather than being visible to a passing driver. The same subsection bans any lighting effect built to look like movement, flashing, intermittent bursts or variable-intensity light, and requires the display to use the most energy-efficient illumination method available. A related subsection, B.10, separately allows electronic message boards to show only time and temperature, provided each message holds for at least 30 seconds, so a static illuminated billboard face is treated differently from a full-motion digital sign, which the movement ban otherwise forecloses.

Where a billboard falls within the Palomar Observatory special lighting area, a buffer zone the county maintains to protect the astronomical research at the observatory from light pollution, subsection B.13 requires the display to also comply with County Ordinance No. 655's separate dark-sky lighting standards, on top of the general no-visible-source and no-flashing rules that apply everywhere else in the unincorporated county. Like the rest of Section 17.252.030, the lighting rule only reaches billboards permitted in the C-1/C-P, M-SC, M-M and M-H zones; it does not regulate storefront, security or residential lighting.