Butte County, CA Outdoor Lighting: Light Trespass & Shielding (2026)

Division 4, Outdoor Lighting, applies only to residential zones under Section 24-63; it does not reach publicly owned facilities, public rights-of-way, or lighting already installed in non-residential zones before the ordinance took effect. The standards became binding on new residential outdoor lighting installed after November 26, 2009, per Section 24-64, and lighting that predated the ordinance and did not comply had to be brought into conformance within three months where simple redirection would fix it, or within six months in all other cases, under Section 24-65.

Section 24-66 lists the ways a noncompliant fixture can be brought into compliance: redirecting it, shielding the lamp, redesigning or relocating the fixture, replacing it with a conforming fixture, or removing it outright. The county's Glossary, Article 42, defines Light Trespass as light falling across a property line onto another lot or a public right-of-way, and defines Adequately Shielded lighting as shielding by opaque materials such that light rays stay on the parcel of origin and the light source itself is not visible from another property or the right-of-way; Figures 24-67-1 and 24-67-2 illustrate the difference between inadequate and adequate shielding.

Limited exemptions exist under Section 24-68 for holiday or temporary lighting used less than thirty days in a year and for temporary law-enforcement or emergency lighting, and Section 24-69 allows motion- or noise-triggered security lighting only if its sensors are not tripped by activity occurring off the subject property. Section 24-70 separately bans flashing or flickering lighting that could be mistaken for traffic or emergency signals.