They are frequently used for fighting fires on docks and shore side warehouses as they can directly attack fires in the supporting underpinnings of these structures. They also have an effectively unlimited supply of water available, pumping directly from below the hull. Fireboats can be used to assist shore-based firefighters when other water is in low supply or is unavailable, for example, due to earthquake breakage of water mains, as happened in San Francisco due to the 1989 Loma Prieta earthquake.