Olympia, WA Outdoor Lighting: Dark Sky Rules (2026)

OMC 18.120.360 is the City of Olympia's outdoor lighting standard for the Downtown design criteria in Thurston County, Washington. It applies to all developments and substantial re-developments in all Downtown Sub-Districts. Its stated intent includes increasing night sky visibility, reducing the general illumination of the sky, and reducing horizontal light glare and vertical light trespass from a development onto adjacent parcels and natural features. The code also wants lighting to enhance the night time pedestrian environment, especially in the Entertainment Sub-District.

The shielding rule is in subsection B.2.a: parking area lighting fixtures must be fully shielded, Dark Sky Approved, and mounted no more than 20 feet above the ground. In the Residential Neighborhood Sub-District the mounting limit drops to 15 feet. The code adds that lower fixtures are preferable to maintain a human scale. Under B.2.b, exterior lighting may not spill onto adjacent properties. Under B.2.c, pedestrian lighting may not exceed 15 feet above the ground, except in parking areas as noted in subsection a.

The code also caps brightness. The maximum exterior light level anywhere within the development is 5 foot candles, measured on the ground. Lighting must be provided at consistent levels, with an average to minimum uniformity ratio no less than 3:1, and highly contrasting pools of light and dark areas are prohibited. A table in subsection B.1 sets minimum, maximum and preferred foot-candle levels by condition, from low-traffic areas and private parking lots up to high pedestrian areas and public parking lots.

These requirements can be set aside only if the applicant demonstrates to the City's satisfaction that there is a compelling reason they cannot be met. Steady, non-flashing architectural lighting of building features, artwork and special landscape elements can be allowed if the applicant shows the light causes no significant adverse impact. Site and building-mounted fixtures must be consistent with the site's architecture, or be unobtrusive with their visibility minimized.