New York Closes High Pressure Stations in Favor of Modern Fire Department Pumpers
—Photo courtesy “WNYF”
Tests develop theory that powerful mobile pumping engines will provide large volume defense at greater economy and efficiency
THE FIRST HIGH PRESSURE fire system of any magnitude in this country, that in Manhattan and downtown Brooklyn, N. Y., officially passed into history on June 29, 1953. Nevertheless, it has not entirely gone into oblivion; certain of its functions continue to serve and doubtless will do so for many years to come.
The system dates back to 1903 when plans for it were made following several large fires which occurred in New York and other cities. Plans reached fruition, and the system went into commission on July 6, 1908, not without some misgivings on the part of skeptics who feared trouble that might eventuate because of the high pressures it might be called upon to withstand.
The original system in Manhattan protected some 2,600 acres and comprised 94 miles of mains 12 to 24 inches in diameter, with 2,065 hydrants. Two pumping stations, one on the North and one on the East River, supplied the water.
The Manhattan system was originally bounded by 23rd Street, Madison Avenue, 24th Street, Lexington Avenue, 14th Street, Third Avenue, The Bowery, East River, Maiden Lane, Nassau Street, Chambers Street and North River. Extensions installed in 1913 and 1914 extended the system to 34th Street in high value areas.
The Brooklyn System covered 2,500 acres, had two pumping stations and 1,230 hydrants. It was originally bounded by the East River, U. S. Navy Yard, Fort Greene Park. Fourth and Fifth Avenues, 39th Street, Gowanus Bay and Erie Basin. The Red Hook and Gawanus extensions were placed in service October 30, 1913.
The initial contract for all the Manhattan installation (with which this report is most concerned) called for delivery of 3,000 gpm by each pump in each pumping station, at a discharge pressure of 300 psi. At their acceptance tests the fire pumps in each station totalled a delivery of about 18,000 gpm. Fresh water for each station was supplied through two 24-inch mains connected with a third of 36 inches. Salt water could be supplied, if need be, from the North and East Rivers, through two 30-inch pipes. The pumps were all of 5-stage centrifugal, electrically operated; each stage designed to give a pressure of 60 psi to a combined pressure of 300 psi with five stages.
The average pressure required for fire duty was 125 to 200 psi at the hydrant and each station working under those conditions could deliver better than 30,000 gpm. It was confidently believed, and never proved otherwise, that with this volume of water concentrated within a radius of 500 feet, no imaginative conflagration could survive its attack.
Two 24-inch mains led out of each high pressure station, intersected at frequent intervals by lateral branch pipes of 12-and16-inch in turn cross-connected by 20-inch mains. The hydrants are connected to the mains by 8-inch branch pipes, gates being provided at intervals of about 250 feet. The system was so planned that without excessive drop in pressure due to friction loss in mains, it was possible to concentrate 20,000 gallons of water a minute upon the average block of buildings, or the full capacity of both stations upon an area of approximately one-quarter of a square mile.
The hydrants selected were furnished with four 3-inch outlets, providing a capacity of four 2-inch streams with 75 psi pressure, and roughly 4,000 gpm.
In order to be certain that valves could Ire opened against the heavy pressureliable to be met in the system lx-forc it w’as formally handed over, extensive tests were made. The first of the two most noteworthy trials occurred along the North Riser. There, twenty-one 3inch hose lines were stretched from seven hydrants, and twelve 5-inch and nine 1 1/2-inch nozzles were used. Within two minutes after the order to start water was given, a nozzle pressure of 80 psi was registered, and so great was the volume of water delivered that “the streets speedily became a lake and overflowed towards the docks,” as Chief Edward Croker’s report described it.
The second test was even more exhaustive. Twelve 3-inch lines with 1 1/2inch nozzles; six Siamese lines with 2inch nozzles; a water tower with a 2-inch nozzle, and a deck pipe with a 1 1/4-inch nozzle, were all brought simultaneously into action. One minute after giving the order to start, a nozzle pressure of 150 psi was obtained, and in two minutes, 195 psi was registered on the 1 Vi-inch nozzles and 170 psi on the 2-inch. With nozzles elevated to an arc of 80 degrees, this pressure carried a solid stream of water 100 feet above the roof of a 14story building.
In December, 1908, the New York Fire Insurance Exchange made a general reduction of rates throughout the high pressure zone in Manhattan.
System met severe test
On January 7, 1909 the system had its first real test. On that day, with streets almost impassable with snow, the temperature just above zero, and winds at 50 mph, at 7:24 pan. the department was called to a fire in a 7-story building at Hudson and Franklin Streets, occupied by a wholesale tea company. With the building heavily involved, and severe exposure hazards, Fire Chief Croker called for a fourth-alarm assignment. While most of this force was still operating on the warehouse fire, a third-alarm fire occurred on the Bowery, and a fifth-alarm blaze on Broadway, all within a square mile area.
—Diagram courtesy “WSYF”
—Photo courtesy “WSYF”
Each of these three fires would have been a fifth-alarm fire under the old order, but all were handled by the high pressure system without any difficulty. It is reported over 14,000,000 gallons of w’ater were delivered from the pumping stations on these fires at a pressure of 225 psi at the hydrant. This was done with but seven of the ten pumping units in service, the other three being held in reserve. Chief Croker said that 100 steam engines would have been required to deliver the same amount of waiter and under the conditions, he doubted very much if it could have been done.
The cost of electric current used at these fires was $1,200.
So much for the historic background of the famous system. From 1908 until 1953 it operated satisfactorily. However, as the years passed, fears increased that the aging system might not be able to withstand the original maximum pressures of 300 psi notwithstanding the fact that it was never called upon to operate at this maximum.*
Some years ago, as a precautionary’ measure, orders were issued revising the maximum dowmvard. Still later, this maximum was further reduced. During these years gasoline-driven pumpers, replacing the old steamers, were quartered throughout the high pressure areas. During the administration of Chief John J. McElligott, orders were issued to utilize the low pressure hydrants, at least for overhauling, to help reduce the costs of power to operate the pumps, and to relieve the distribution system of pressures higher than those which it normally maintained (75 psi).
Continued on page 991
* Section III, Special Order 105, June 26, 1953, stated, “The High Pressure Pumping Stations in Manhattan and downtown Brooklyn will bo discontinued at 8 A.M. June 29, 1953. However, arrangements have been made with the Department of Water Supply, Gas and Electricity to maintain the present high pressure hydrants and mains, and in addition there will be available at least 30,000 gallons per minute at a residual pressure of 100 pounds to 125 pounds on the system at all times.
Proposals for the maximum pressure on the system called for 400 psi “higher than any heretofore known pressures on fire mains” (Fire Water Engineering, Feb. 23, 1907) In the original agreement, also, with the New York Edison Go. it was stated, “Failure of the NYE Co. to supply 400 psi within three minutes would result in a fine of $500 per minute.” However the maximum limit ordered by the department was set at 300 psi.
HIGH PRESSURE SYSTEMS
Continued from page 937
As time passed and the costs of fire protection in all of its phases increased, the high pressure system came under increasing scrutiny. With expense to operate the four pumping stations a growing burden, and the prospect of diminishing efficiency becoming more real, fire officials raised the question of whether the system was any longer justified.
As a substitute it was suggested: Why not dispense with the high pressure pumping units and attendant maintenance costs, but utilize the distribution layout, as part of the low pressure domestic service?
To do this would mean strengthening the department’s mobile pumping capacity which, many believed, would have to be done anyway. Fire department engineers were recommending 1,000 gpm pumpers for the city’s high value areas and with these available to utilize the high pressure mains, and if necessary, the regular low pressure domestic distribution system, it was believed through them as much water could be delivered onto any fire in the areas as could be delivered by the old high pressure system. At the same time, the department would be providing more powerful mobile force for the protection of other areas, if required.
But sound as was the reasoning in most respects, the idea of eliminating the old system had its “Doubting Thomases.” There was but one way to settle the problem, and that was to try it out.
CD test held
With an approving fire commisioner and capable department staff, this was done. In fact, the test went further than merely to determine the capabilities of the old distribution system operating with gravity pressure. It afforded an opportunity to school the department’s auxiliary firemen and to enable the officers to acquire experience in Civil Defense procedures.
The tests also permitted the first largescale use of the new Civil Defense pumpers which had been added to the department under the Federal matching funds program.
.The trials got under way Sunday, June 14, 1953, and were carried out in three stages. In the first phase, 20 of the 750 gpm pumpers under the supervision of the then Chief of Department, Peter Loftus, were mobilized on the West side of Manhattan, between Tenth and Eleventh Avenues, and 15th and 21st Streets below Oliver Street Pumping Station.
For the purposes of this experiment, the Oliver and Gansevoort Pumping Stations were valved off from the high pressure mains, which were fed only by gravity pressure from Shafts 18 and 19 of the Catskill Water Tunnel No. 1. In general, the 20 pumpers were located two to a hydrant, similar to the accompanying diagram of Phase 3.
In the Phase 1 test the 20 CD pumpers simultaneously delivered 775 to 800 gpm each. The. total discharge was 15,750 gpm. The lowest residual pressure on the mains, checked in the vicinity of Gansevoort Street, was 67 psi.
In Phase 2, 20 of the 750 gpm pumpers were located on the east side, Roosevelt to Pine Streets and South to Water Streets. They delivered simultaneously 775 to 800 gpm, with a total discharge of 15,750 gpm. The lowest residual pressure on the mains in the vicinity of Oliver Street was 57 psi.
In Phase 3, 40 of the same type pumpers were also located on the east side, between Roosevelt and Pine Streets and South and Water Streets as diagrammed herein. These units delivered simultaneously 775 to 800 gpm with a total discharge of approximately 30,000 gpm. The lowest residual pressure during this test on the mains approximately 100 feet beyond the test location was 30 psi.
In each phase of the operations, two 3-inch hose lines were stretched from a high pressure hydrant to the rear suction inlet of each pumper, which were stationed at hydrants as indicated. All pumpers operated at 125 psi engine pressure in the capacity position with the relief valve locked out, discharging directly into the deck pipe fitted with a 1%-inch tip. The deck pipes were operated at an angle of 60 degrees from the horizontal and streams were directed down the center of the streets to avoid damage to property.
Pitot readings on the deck-pipe nozzles revealed the discharges of 775 to 800 gpm at the 125 psi engine pressures. Fluctuations in engine pressures and incidental shutdowns to clean strainers, prevented an absolute figure being obtained by the supervising engineers for the maximum flow. However, it was established that with 40 pumpers operating as described (Phase 3), a maximum slightly in excess of 30,000 gpm was obtained.
Quoting from W.N.Y.F., official magazine of the New York Fire Department, with all hydrants closed the Catskill water maintained 117 psi at the Oliver Street Station and 112 psi at the Gansevoort Street Station. At peak flow the lowest reading at the Oliver Station was 57 psi and in the Gansevoort Station it was 67 psi. Flows at the hydrants were as beforementioned.
These residual pressures at peak flow indicated that sufficient pressure remained in the mains to afford protection to other areas, or to supply greater volumes had the circumstances been different.
Simultaneous flow was assured by having one chief officer with 2-way mobile radio supervise each five pumpers under the over-all command of the chief of department, who directed his operations through the city-wide radio network.
The Manhattan Central Office dispatcher transmitted the high pressure breakdown signal 13-13 at 10:55 a.m. and it was not until 2:15 p.m. that he ordered the restoration signal 9-9-9 transmitted.
During those 3 hours and 20 minutes, radio enabled the chief of department and his aides to keep in constant touch with the Manhattan dispatcher, prepared to immediately cut in the high pressure pumping stations, should fire conditions so require.
Beginning in January 1952, flow tests were conducted on the Manhattan and the downtown Brooklyn high pressure systems by New York’s Department of Water Supply, Gas & Electricity to determine whether Catskill water, at gravitypressure, could match the fire fighting efficiency of Croton water at pumped pressures. These tests indicated that the high pressure mains, using Catskill head would provide sufficient water at feasible pressures to control fires at different points throughout the system with ample residual pressure in the mains.
Great saving to city
The elimination of the four high pressure pumping stations in Manhattan and Brooklyn, it is said, would result in capital savings of approximately $2 million, make available city properties valued at approximately $1 million, and cause reductions in operating costs of over $275,000 per year.
What the heads of department were primarily concerned with in weighing any change in the high pressure system protection, is fire safety in the same areas protected by that system. Huge daily populations, immense concentration of wealth, and extra heavy traffic and narrow streets, make first-rate fire protection imperative now, even more so than in the days of the horses.
Before the fire department would experiment with the Catskill gravity supply, several stipulations were laid down. These included:
- The present piping system, including hydrant and control valves, should remain in its entirety throughout the high pressure system and should be maintained in first-class condition, completely purged of sediment, scale and foreign matter.
Two additional connections to Catskill Water Tunnel No. 1 at Shafts 20 and 21 should be made to supplement the two existing connections.
- Every engine company in the high pressure district should have its manpower increased by one additional fireman per tour of duty.
- All engine companies in tire high pressure district should be equipped with first size pumpers.
Under these conditions, the New York Board of Fire Underwriters was informed of the proposed change and reported they had no objection to the proposed procedure. As was pointed out by fire department officials, when the high pressure system was put into operation in 1908, it was a tremendous improvement over the horse-drawn steamers of that time. However, conditions have since changed greatly in the city. Buildings are much taller, and the high pressure system can no longer supply water to the top floors of the higher structures. Today, the department has efficient, modem gasoline pumpers capable of developing pressures up to 600 psi on volume delivery.
Present 4-stage pumpers now in use in the high pressure areas are rated at 1,000 gpm at 160 psi; 500 gpm at 320 psi; 400 gpm at 400 psi and 250 gpm at 600 psi. They are perfectly capable of supplying an effective 2 1/2-inch line at the maximum pressure.
There are at this writing 25 of the 1,000 gpm pumpers in Manhattan’s old high pressure district. The performance of these pumpers at the Wanamaker fire was described in the August issue of FIRE ENGINEERING. These pumpers shortly will be augmented; the fire department s 1956-7 budget includes provisions for 32 additional 1,000-gpm pumpers. In addition, further pumping strength is being provided for the city’s expanding fire department.
New York is not the only city that has either discontinued all or part of its high pressure system, or plans to do so. Detroit is another to weigh its high pressure layout and come up with the decision to shelve it. Future developments in this field of fire protection will be watched with keen interest by fire and water works officials throughout the nation.
The editors gratefully acknowledge the assistance of Fire Commissioner Edward F. Cavanagh Jr., Fire Chief Edward Connors, the Chief Supervising Engineer of the department Harry Irwin and his aides and Hon. Battalion Chief and Department Historian Clarence Meek for their assistance in providing the factual data upon which this account is based. Spedal appreciation is also extended to W.N.Y.F., official magazine of the New York Fire Department.