Lake Steilacoom is a reservoir approximately 4 km (2.5 mi) southwest of Tacoma in Pierce County, Washington, United States. Its boundaries lie entirely within the city of Lakewood, Washington. The reservoir covers approximately 53 acres (210,000 m²), has a mean depth of 11 feet (3.4 m) and a maximum depth of 20 feet (6.1 m). Lake Steilacoom is a freshwater lake and drains into Puget Sound via Chambers Creek, which begins at its northern tip.