POL Government Elected Officials Auditor Mary Hull Caballero Charter, Code and Policies City Code & Charter Online Code & Charter Title 19 Chapter 19.16  Rules And Regulations
19.16.035 Vessels Changing Docks.

Every vessel, unless propelled by its engine, moving from one dock to another or from one place to another when necessary to pass through the draw of any bridge or when moving from a dock or wharf to a dock or wharf within the City shall, in order to prevent the obstruction of travel, have the services of a tug or tugs.