The Auxiliary Water Supply System (AWSS, though often referred to on manhole covers and hydrants as HPFS for High Pressure Fire System) is a high pressure water supply network built for the city of San Francisco in response to the failure of the existing emergency water system during the 1906 earthquake. It was originally proposed by San Francisco Fire Department chief engineer Dennis T. Sullivan in 1903, with construction beginning in 1909 and finishing in 1913. The system is made up of a collection of water reservoirs, pump stations, cisterns, suction connections and fireboats. While the system can use both fresh or salt water, it is preferential to not use salt water, as it commonly causes galvanic corrosion in fire equipment.
The Auxiliary Water Supply System (AWSS, though often referred to on manhole covers and hydrants as HPFS for High Pressure Fire System) is a high pressure water supply network built for the city of San Francisco in response to the failure of the existing emergency water system during the 1906 earthquake. It was originally proposed by San Francisco Fire Department chief engineer Dennis T. Sullivan in 1903, with construction beginning in 1909 and finishing in 1913. The system is made up of a collection of water reservoirs, pump stations, cisterns, suction connections and fireboats. While the system can use both fresh or salt water, it is preferential to not use salt water, as it commonly causes galvanic corrosion in fire equipment. The large, white oversized hydrants that are supplied by the AWSS/HPFS, of which there are 1889, are visible throughout the city. The hydrants have painted tops that are color-coded as to zone: * Black topped hydrants are in the West of Twin Peaks zone, and are fed by the Twin Peaks Reservoir. * Red topped hydrants are in the upper zone, and fed by the Ashbury Street tank. * Blue topped hydrants are in the lower zone, fed by the Jones Street tank. (en)
The Auxiliary Water Supply System (AWSS, though often referred to on manhole covers and hydrants as HPFS for High Pressure Fire System) is a high pressure water supply network built for the city of San Francisco in response to the failure of the existing emergency water system during the 1906 earthquake. It was originally proposed by San Francisco Fire Department chief engineer Dennis T. Sullivan in 1903, with construction beginning in 1909 and finishing in 1913. The system is made up of a collection of water reservoirs, pump stations, cisterns, suction connections and fireboats. While the system can use both fresh or salt water, it is preferential to not use salt water, as it commonly causes galvanic corrosion in fire equipment. (en)
