Washington's Department of Ecology has a robust response plan for oil spills. They have to, because there's an oil spill of some kind every day in Washington.
Ecology spokesperson Larry Altose said sometimes it's the result of a traffic accident and sometimes they find an area of sheen but can't identify the source, especially in high traffic areas.
A spill Tuesday morning in the Duwamish West Waterway was larger than normal.
Diesel oil spilled directly into the Duwamish, close to where the river flows under the West Seattle bridge. Officials say a tug boat ran into a barge, piercing the fuel tank in the barge and letting fuel leak out.
Up to 1,200 gallons of diesel may have spilled into the west waterway, according to the Department of Ecology. Altose said they took it seriously because of how harmful fuel is to Puget Sound's birds and marine life.
Altose said staff at Island Tug and Barge sprang into action to contain the spill within minutes.
"Booming it immediately was exactly the right thing to do, but there is some amount of oil, even after cleanup is very successful, that does work its way into the water and adds to the toxic impact of Elliot Bay and Puget Sound," Altose said.
Altose said ecology and U.S. Coast Guard crews are overseeing the cleanup work.
He said spill response teams have not observed any impacts to fish or wildlife and have seen birds in flight nearby since the spill. This time of year the central Puget Sound is home to bald eagles, peregrine falcons, seals, juvenile salmonids, Dungenes crab and clams, and other species.
Officials have not announced the cause of the tug boat crash.