SPRING VALLEY WATER WORKS.
THE business of the Spring Valley, Cal., Water Water increases yearly—834 new water takers having been added in San Francisco, Cal., last year to the 40,189 of the preceding year. The consumption of water was 8,667,000.000 gallons, 900,000,000 gallons more than in 1896. The income has been $1,794,638.65, of which $1,775 129.25 was received from water rates. The operating expenses were $388 364 27; taxes. $102,932.05 both of which, added to coupon and other interest, Caused an expenditure of $1,023,701,74—add dividends. $778,006, and the loss was $71063.09. Last year a new settling reservoir was built at the south end of lake Merced, and the capacity of the old one was largely increased by raising its dam fully six feet. A large, substantial, brick tuunel leading therefrom to the ocean tunnel—a distance of fully 4,000 feet was also built. Its outlet is two and one-halt feet above high water tiae. Another tunnel—the Davis —has also been built, 1,200 feet long, four feet, four inches shed to San Andreas lake. Another, with a large flume and pipe line, is being built, which will still further add to the watershed of that lake, A large redwood asphaltum-lined flume one and one-half miles long, has been constructed .conveying the flood water of the Ocean View canyon into the lower settling pond, from which, with the water from the Colma canyon, it flows through the brick aqueduct and tunnel already mentioned into the ocean, whereby lake Merced is protected from pollution. A x.ooo.ooo-gallon brick and cement reservoir has been built on the summit of Ptotero Heights 300 feet above tide, which gives San Francisco a good fire protection. This reservoir is supplied by a twelve-inch main pipe fully two miles long, and a large screenhouse, with a capacity to screen 16,000 coo gallons a day, has been built at the University Mound reservoir. The pressure on the fire hydrants has been greatly increased by laying thirteen miles eighty-six one-hundredths of main pipes in the city. A pumping plant, capacity 4.500,000 gallons, has been built at the outlet of the San Andreas tunnel, and a large cast iron force-main has likewise been laid connecting the station with the main Pilarcitos pipe line on the top of Bald hill. Another pumping plant— daily capacity 16.000 000 gallons—is being built near Millbrae to pump the water of Crystal Springs and Alameda creek up into the San Andreas pipe line through a new wrought iron thirtyinch main,7.000 feet in length to an elevation of 400 feet above tide. This will avert, if possible, a scarcity of water on the higher levels in the city in case of a scarcity of rainfall San Francisco now enjoys one of the best water supplies in the world; but enjoys it only through the Spring Valley Company having surmounted unusual difficulties. California has seen two successive winters of unusually light rainfall—a danger which had to be guarded against for the future. Fully a twoyears’ supply had to be artificially impounded and held in re. serve for the successive dry years. Hence the great outlays on the part of the water company in obtaining hundreds of square miles of watershed, building reservoirs.etc.—an expense which would be many times increased, if similar steps had to betaken to afford New York a two-years’stored supply. This water is needed in San Francisco at least as much for fire protection as for other purposes. The city is essentially one of wooden buildings—each one dried up by the summer’s heat into a veritable tinderbox, and affording the amplest material for a fierce conflagration. It is, however, most significant (as the report points out that
under these conditins no serious conflagration has visited San Francisco since the water works were built Twice prior thereto fire had swept it to the ground. Chicago. Boston, Baris. London, and other large cities have been visited by conflagrations.destroying hundreds of millions of dollars’ worth of propety Their regulations for the prevention of fires—far more stringent than ours, with their brick and stone—have not protected them. The vulnerability of these cities, in the face of the immunity of San P’rancisco. is explained by the recent conflagration in London, which destroyed $25,000,000 worth of property. If that city had enjoyed our water pressure the calamity could not have occurred. Its absence occasioned a loss in one night of marly as much as the whole cost of the Spring Valley water works. The reports of that fire comment upon the fact that the streams of water thrown upon the flames did not reach above the second floor of the sixstory buildings. The firemen could fight the fire only below, while the flames were spreading above; consequently, they were powerless to stay the progress of the flames, though the buildings were constrrcted almost entirely of brick and stone. This condition of affairs may be understood when it is known that the vLater supply of London is delivered through the mains under a low pressure, and renders no assistance to the fire enengines.
The report strikingly adverts to the contrast afforded between New York’s distributing reservoir system, only 112 feet above tide,and that of San Francisco with its nine distributing reservoirs in different parts of the city—to which a tenth is about to be added at an elevation of 300 feet above the sea and a capacity of too 000,000 gallons. These reservoirs are as follows,with their height above tide; Clarendon Heights reservoir, 600 feet; Lake Honda reservoir. 377 feet; Clay street hill reservoir, 375 feet; Holliday hill reservoir. 375 feet; Russian hill reservoir, 306 feet: Protrero Heights reservoir. 300 feet; College hill reservoir, 210 feet; University Mound reservoir, 175 feet; Francisco street reservoir. 139 feet.
It is this elaborate high distributing system (the report claims) that has protected San Francisco from conflagrations. The water in the hydrants gives a pressure to the engines of from forty to seventy pounds to the square inch, thereby greatly increasing their efficiency. Each householder has a garden hose —a private fire department of his own—capable of extinguishing an ordinary fire in any part of his house. As a result.onehalf of the accidental fires in the city are extinguished without calling out the fire department. The company has been put to a very large additional expense in rendering this protection so complete. It would have cost but a small portion of what has been expended lad the supply been intended only for domestic purposes. Many of the reservoirs that have been built at an expense of hundreds of thousands of dollars, in order to furnish pressure in every part of the city, would have been unnecessary.