HIGH PRESSURE SERVICE IN BOSTON
The following description and brief historical sketch of the Baston, Mass., high pressure system is published by courtesy of Commissioner L. K. Rourke of the Public Works Department of that city:
The construction of a high pressure fire service system in Boston was authorized under Chapter 312 of the Acts f 1911. This act was accepted by the Mayor and City C uncil. and on July 1. 1911. the first appropriation was made for he work. While actual construction has been delayed owing to difficulty in determining upon the location for the pumping station, the survey and general studies have been vigorously prosecuted and a large amount of material has been contracted for and delivered in Boston. The area to be protected by the proposed syystem contains about 550 acres comprising the entire congested value district as classified by the Board of Underwriters and adjacent territory thereto in the down town section of the city. The system has been designed to deliver 20.000 gallons of water per minute about any single block, and 10,000 gallons of water per minute upon any single building. A reliable and adequate source of supply is available from a 30-inch low service distribution main which is capable of furnishing all the water needed from two directions; also a 30-inch high service distribution main is being laid which will, when completed, furnish an adequate high service supply for the station. In addition to these two supplies from the distribution system, a salt water emergency connection will be„provided ample for all contingencies. The puinping station will be situated on Fort Point Channel southerly from Summer street, in a location imemdiately adjacent to the area to be protected and removed from any serious fife risk. Motor driven centrifugal pumps will “be installed, electrical energy being supplied from two separate power plants. Each pump will have a capacity of 3,000 gallons per minute at pressure of 300 pounds per square inch. Separate fireproof rooms containing the high voltage electrical parts will be located in the rear of the switchboard from which the pumps and motor operated valves will be controlled. Fire alarms and orders from the fire department will be received over a fire alarm sircuit and a separate signal system. Telephone service over duplicate lines will also be provided. A duplex distribution system composed of two independent pipe systems with mains on alternate streets has been designed, thus ensuring a continuity of water supply in case of the failure of a main in either leg of the system. Cast iron has been selected as the material for the distribution mains. About 13 miles of pipe from 12 to 20 inches in diameter will be required to complete the system now proposed. The mains will be so equipped with gate valves that a break in the pipe will not put more than three hydrants out of service. The valves and hydrants adopted were designed by the department. About 450 hydrants will be required on the basis of providing a hydrant for each 10.000 square feet.
After eighteen months of engineering study and experiments with the various details of des’gn, the building and testing of three different hydrants of the same general type, and a successful fireboat test of the third design. : he Boston Public Works Department adopted for the high pressure fire service the Rourke hydrant, designed by J. A. Rourke. The hydrant was designed for a normal delivery of 2.000 gallons per minute. For the friction loss tests a maximum of 3,000 gallons per minute was obtained and during the fireboat test over 3.600 gallons per minute, maximum capacity available, went through the hydrant. The contract for hydrants called for approximately 410 hydrants and that the hose nozzle be in accordance with the City of Boston standard and standard female coupling templets shall be provided by the contractor to insure that each nozzle is suitable for receiving the 2⅛inch hose coupling in service.