The Portsmouth Water System

The Portsmouth Water System

Water is supplied to the city of Portsmouth, Va., by the Portsmouth, Berkley and Suffolk Water Company (controlled by the American Water Works and Electric Company), and likewise supplies water to Suffolk and the Berkley ward of Norfolk. Built up territory in counties outside the corporate limits is supplied by the Portsmouth Suburban Water Company, controlled and operated by the same interests. G. W. Biggs, Jr., is chief engineer, and the local management is vested in W. L. Davis, who has been superintendent for 11 years. The sources of supply, states a report on conditions in Portsmouth, recently issued by the Committee on Fire Prevention of the National Board of Fire Underwriters, are four lakes with a watershed of 100 square miles and an estimated yield of 50,000,000 gallons per day. Burnt Mills Lake with a watershed of 30 square miles and Phillips Lake with 20, are not yet developed. Lake Cahoon impounds 450,000,000 gallons. Lake Kilby, the main source of supply, holds 600,000,000 gallons. The Suffolk stations, located at Lake Kilby, are three stations, two of which are in reserve. The low lift pumps have a total capacity of 16,000,000 gallons per day. The total capacity of high-lift pumps is 10,500,000 gallons. Either the 5,000,000or 6,000,000-gallon pump in the main station is generally used, the remaining units being held in reserve, and used only occasionally; the turbine pumps could be used only during a small part of the year. Pressure ordinarily maintained from 70 to 75 pounds, can, in emergency, be raised to 100 pounds. At the Godwin street station the total rates capacity of three pumps is 13,500,000 gallons. A 20-inch cast-iron supply main extends along the railway right-of-way from the Suffolk stations through Suffolk to Portsmouth; this line was laid in 1888 and for a short distance is supported upon piles. A second 20-inch line, about 20 feet away, was completed in 1911, from Suffolk to within about 1,700 feet of the Godwin street station, where it joins the original main; the Suffolk distribution system is supplied through a part 12-inch but mainly 16-inch line from the Suffolk stations. These mains are Class B, American Water Works Association, pipe and are cross-connected and gated at eight points along their route; total length, approximately 17 miles. At the Godwin street station the supply main is arranged to deliver into the storage basin, direct to the pumps, to the standpipe or directly into the distribution system. An open storage basin built adjacent to the Godwin street station, about 20 years ago, partly in excavation, of brick, stone and cement, is 100 feet in diameter and 14 feet deep. The basin furnishes suction supply under slight head. In ordinap’ practice the depth of water in this reservoir is not allowed to exceed 11 feet, or a storage of 650,000 gallons. At the Godwin station is a standpipe of about 500,000 gallons capacity, normally acting as a pressure equalizer on the distribution system; at time of fire it is shut off from the distribution system; connections are made which permit the storage in this standpipe to be delivered to the suction of the pumps. The average daily consumption in 1914 was 3,256,000 gallons being 77 gallons per capita. At the time of the report there were 8,000 service of which 650 were metered. Distribution is in one service supplied by continuous pumping from the Godwin street station. From the pumping station a 12-inch main extends northerly and easterly to the northern limits of the principal mercantile district; a 14-inch main extends easterly from the pumping station and reducing to 12-inch parallels the principal mercantile district two blocks to the west. The 16-inch supply main to Berkley extends northerly and easterly from the station and passes the principal mercantile district along its southern boundary; the gates in its three connections with the Portsmouth distribution system are normally closed. Ten-inch mains are used as secondary’ feeders and are fairly numerous. Minor distributers are mainly 6-inch w’ith a considerable proportion of 4inch and some 8-inch. All mains are tar-coated cast-iron. Original mains are still in service, but a considerable portion of the larger pipes have been laid during the past 10 years. No trouble has been experienced from tuberculation in the mains. Mains are laid with cover of three feet. Frost penetration rarely exceeds six inches. The distribution system of Suffolk and the supply mains to Portsmouth have weights of pipe corresponding to Class B of specifications of American Water Works Association, the weights in Portsmouth corresponding to Class A. There are 351 gate valves. There are 167 post hydrants of Chapman and Ludlow makes. The city has appointed a Board of Water Commissioners, Wm. G. Parker, president, and T. J. Wright, Jr., engineer in charge, to provide for a municipal water supply. A canal about 12 miles long has been built from Lake Drummond, in the Dismal Swamp, to a point about 5 miles southwest of the city. Tentative plans include a filtration plant and pumping station supplying a distribution system consisting of a gridiron of sixto 20-inch pipe for hydrant supply, with four-inch pipe for domestic supply in the intervening streets. The report recommended that the second 20-inch line from Suffolk be completed to the Godwin street station. That a storage basin of at least 2,000,000 gallons capacity be constructed near the Godwin street station. That a boiler and a pump of 6,000,000 gallons capacity be added to the Godwin street station, so that both boiler and pumping capacities may be ample with one unit of each out of service. That additional hydrants be installed.

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