It is unclear exactly how much sewage spilled, but Environmental Health Services director Phil Smith said the maximum amount is 1,000 gallons, the total capacity of the two tanks on board the ferries.
Environmental Health Services tested the water Monday and put up warning signs advising swimmers, sport fishermen and other recreational water users to avoid the area for a half-mile on either side of the ferry terminal.
However, Smith said today the water meets state standards for recreational water contact.
Smith said the samples were taken from near the vessel dock adjacent to where the spill occurred; San Quentin Beach; and upstream at the Marin Rowing Association in Greenbrae.
More tests were taken this morning and the results should be available by noon Wednesday, Smith said.
The spill occurred along a pipe at the dock through which sewage is pumped from the ferries to the sanitary district, Smith said.
Environmental Health Services was informed of the spill at around 9:45 a.m. Monday, Smith said.
James Swindler, deputy general manager of the Golden Gate Ferry Division, did not immediately return calls for comment today.