Duwamish was one of the most powerful fireboats in the United States several times over her 75-year working life. She is the second oldest vessel designed to fight fires in the USA, after Edward M Cotter, in Buffalo, New York.
Duwamish was built in 1909 for the Seattle Fire Department in Richmond Beach, Washington, just north of Seattle. She was powered by "double vertical (compound) marine steam engines" capable of driving her at 10.5 knots (19.4 km/h; 12.1 mph). She was equipped with three American LaFrance steam piston pumps rated at a capacity of 3,000 US gallons per minute (0.189 m3/s) each. She was originally designed to ram and sink burning wooden vessels, as a last resort, and was equipped with a ram bow for doing so.
On July 30, 1914, Duwamish was involved in fighting the fire on the Grand Trunk Pacific dock.
After an upgrade in 1949, the pumps delivered a total of 22,800 US gallons per minute (1.438 m3/s). This capacity was only exceeded in 2003 by the Los Angeles Fire Department's Warner Lawrence, which delivers 38,000 US gallons per minute (2.397 m3/s).
Duwamish is 120 feet (36.6 m) long with a 28-foot (8.5 m) beam and a 9.6-foot (2.9 m) draft. Her registered gross tonnage is 322 short tons (292 t).
Retired in 1985, Duwamish was purchased by the Puget Sound Fireboat Foundation, which is maintaining and restoring the vessel. Duwamish is active in the local Sea Scouts organization, a program of the Boy Scouts of America. She is permanently moored at the Historic Ships Wharf near the Museum of History & Industry at South Lake Union Park in Seattle. Visitors may board the vessel when volunteer staff is available.
Duwamish was declared a National Historic Landmark in 1989.