She was leased by the Navy, and outfitted as an armed section patrol craft, assigned to patrol and protect San Francisco harbor.

She was leased from the San Francisco Bar Pilot's Association and commissioned in the Navy as USS California (SP-647) on 28 April 1917.

Later renamed USS SP-647, the motor boat performed harbor patrol duties and acted as guard boat for Pier 29 at San Francisco until 23 November 1918 California (No.

647) was returned to the San Francisco Bar Pilot's Association on 23 November 1918.

The San Francisco Maritime Museum, located in the San Francisco Maritime National Historical Park, holds additional photographs of the pilot boat California in its Livingston Collection.