Kennewick, WA Outdoor Lighting: Light Trespass & Shielding (2026)

KMC 18.39.020(11) defines "Light Trespass" as "the shining of light produced by a luminaire beyond the boundaries of the property on which it is located," and KMC 18.39.030 sets the fix: subsection (1), Uplight Shielding, requires that "the center of light source shall be level or above the edge of the light fixture so that direct light emitted above the horizontal is minimized," with refractors required where shields are not used. Subsection (2), the "Good Neighbor" shielding rule, goes further and directly targets trespass onto adjoining land, requiring fixtures to be "shielded in a manner that directs light downward and limits direct line of sight of a fixture's lamp to the property upon which the fixture is installed." Light poles may not exceed the height of the nearest streetlight except at sports complexes, and parking areas must be illuminated. Non-conforming fixtures are grandfathered but lose that status, and must be brought into compliance, if the fixture is modified, moved, or replaced, or if the property use changes, or if improvements exceed 20 percent of the property's assessed value.

Several categories are excluded from the shielding standard under KMC 18.39.050: fixtures installed before November 12, 1973; private residential lighting under 1,800 lumens; gas-combustion light; neon signage; seasonal decorations lit no more than 60 consecutive days; and motion-activated security lights that shut off within ten minutes. Separately, KMC 18.39.040 makes it unlawful to illuminate an outdoor recreation facility after midnight without an activity in progress, or to floodlight a building or sign above the horizontal between midnight and sunrise. A private single-color searchlight is allowed only for community events with the Director's written approval, up to three days a year, and never for commercial advertising. Because Chapter 18.39 sits within the zoning title, violations are processed as Title 18 code violations under KMC 9.48.020, which lets the Director issue a notice and order, assess civil penalties, and refer willful violations to the City Attorney; any court action must be brought within one year of the violation under KMC 18.39.070.