Tolmie State Park

Tolmie State Park sits on the south shore of Nisqually Reach in Thurston County, on the Olympia edge of Puget Sound at 7730 61st Avenue Northeast. The park covers 154 acres of marine day-use land with 1,800 feet of saltwater shoreline at the mouth of Big Slough. Washington State Parks describes the offshore area as an "underwater park" built around sunken barges and an artificial reef added over the years by volunteer divers. Shore entry runs from the beach at the end of the park boardwalk.

The park is named for Dr. William Fraser Tolmie, an early Puget Sound physician and Hudson's Bay Company officer. Its artificial reef grew out of a broader 1970s and 1980s Puget Sound program to build artificial reefs from bundled scrap tires, with volunteer divers adding barges and additional structure over the years. That tire program failed as the polypropylene twine binding the tire bundles broke down and tires spread across the seafloor, and in late 2024 the Washington Department of Natural Resources began pulling more than 100,000 tires off 14 identified Puget Sound sites, including this one. Approximately 2,500 tires were removed from Tolmie in the two-site pilot cleanup, part of 4,701 tires total across both pilot sites, using an excavator and a dive team. As of 2026 the sunken barges remain as underwater park structure while the tire component of the reef is still being actively removed under the DNR program.

Two biomes overlap on the site. The gently sloping sand along the beach entry near shore reads as a surf zone biome, the shallow water that makes the site a workable training dive. Farther out, the sunken barges and the volunteer-built reef structure form a rocky reef biome around the artificial structure that carries the site's resident fish and invertebrate community. Scuba is the practical use of the site.

Parking is at an automated pay station in the state park lot, and a Discover Pass is required; accessible parking, restrooms with drinking water, picnic shelters, and a boardwalk to the beach are all on site. Summer hours run from 8 a.m. to dusk and winter hours from 9 a.m. to dusk. Ongoing DNR barge and dive-team cleanup operations may be present on some days depending on the removal schedule. Marine Area 13 rules govern harvest at the site: all rockfish are closed to retention year-round, and lingcod spearfishing runs only from May 21 through June 15 under a 26 to 36 inch slot and a one-fish daily limit; giant Pacific octopus and wolf eel are protected as no-take species statewide, and those closures have been enforced by WDFW under Washington fishing rules.