Birch Bay State Park, State park in Whatcom County, US.

Birch Bay State Park covers 225.1 acres nine miles south of Blaine in Whatcom County, within the town of Birch Bay. It has 7,915 feet of saltwater shoreline on Birch Bay and 15,000 feet of freshwater shoreline along Terrell Creek. Visitors come for camping, picnicking, fishing, hiking, crabbing, clamming and boating.

The park contains archaeological site 45-WH-9, known to local native peoples as Strav-a-wa, recorded since 1963 and one of the largest sites in the area. Excavations in 1975 and 1976 uncovered large amounts of domestic dog (Canis lupus familiaris) bones. Little archaeological work has been done there since.

The park takes its name from Birch Bay, whose shores are lined with birch trees. Within the park lies the archaeological site 45-WH-9, known to local Native peoples as Strav-a-wa, recorded since 1963 and one of the largest sites in the area. Excavations in 1975 and 1976 uncovered large numbers of domestic dog bones.

The park lies nine miles south of Blaine in Whatcom County, with 7,915 feet of saltwater frontage on Birch Bay and 15,000 feet along Terrell Creek. Camping, picnicking, fishing, hiking, crabbing, clamming and boating are all possible; the saltwater shore is the closest water to the campground. A vehicle fee applies at entry, so carry a park pass or permit.

The Terrell Creek Marsh within the park is one of the few remaining places along northern Puget Sound where freshwater and saltwater naturally mix. This rare ecosystem attracts bird and fish species that you rarely see elsewhere in the region.