Olympia, WA Environmental Rules: Boat Dock Permits (2026)

Residential moorage in the City of Olympia, Thurston County, Washington, is governed by the Shoreline Program in Chapter 18.20 of the Olympia Municipal Code. Section 18.20.844 sets the core rule: shared residential moorage is required unless the applicant demonstrates why it is not feasible, and moorage for a new subdivision of more than two lots or a multi-family development of more than two dwelling units must be shared. Shared moorage proposed for lease to five or more upland property owners is reviewed as a marina under OMC 18.20.654. Where individual moorage is allowed, only one type of facility is permitted per waterfront lot, and residential boat lifts are permitted.

A Shoreline Substantial Development Permit is required for all proposed use and development of shorelines unless the proposal is exempted under WAC 173-27-040 and RCW 90.58 (OMC 18.20.210). The decision maker must find the proposal consistent with the Shoreline Program, conditions can be attached, and the City is the final authority unless an appeal is filed with the State Shorelines Hearings Board. Under OMC 18.20.220, an exempt development still must meet the Shoreline Program, and a letter of exemption is required when a U.S. Army Corps of Engineers Section 10 or Section 404 permit applies.

Dimensional limits depend on the water body. In fresh water, new or expanded private piers or docks cannot exceed fifty feet from the Ordinary High Water Mark. Only piers or ramps can sit within the first thirty feet water-ward of that mark, and docks must stay ten feet from the side property line. Surface coverage is capped at 480 square feet for single use, 700 square feet for two-party joint use and 1,000 square feet for three or more residences, with a four foot width limit (OMC 18.20.847). In marine waters, the limit is 100 feet from the mean higher-high water mark, the side setback is twenty feet, residential piers cannot exceed 4 feet in width, and creosote or pentachlorophenol treated wood is barred (OMC 18.20.846).

General moorage rules in OMC 18.20.840 prohibit docks, piers and floats where the distance to the opposite shore is 150 feet or less, and new overwater covered moorage is prohibited. Moorage buoys are limited to one per waterfront lot, and each must be discernible in daylight at 300 feet (OMC 18.20.842). Recreational floats are capped at 64 square feet for a single owner and 96 square feet for multiple owners (OMC 18.20.848).