ROCHESTER WATERWORKS SYSTEM
Improvements at Rush Reservoir.
Special correspondence of FIRE AND WATER ENGINEERING.
(WITH INSET.)
罗切斯特（Rochester）由Genesee河从北到南，在公司范围内有三只瀑布和几起急流，总下降约257英尺，为许多制造业提供了权力。Genesee的排水区域为2,365平方英里，伊利运河（Erie Canal）有几条重要的树干线，进入并穿过城市。它的宜居区域为10,526英亩 - 16.447平方英里；它的公园，河流等是1,307英亩 - 2.04平方英里，总计11,833英亩 - 18.489平方英里。Waterworks系统由城市拥有和运营，使用了两个系统，（1）饮用水的重力系统，（2）从Genesee River取的直接（Holly）抽水系统。重力系统的来源是Hemlock Lake，位于南部30英里的丘陵区，高约386英尺。这个湖泊在普通低水位的面积为1828英亩；它的平均深度在中间为65英尺。它的排水区（包括水面）为48.00平方英里；可以向Hemlock Lake进行支流的总排水区为66.20平方英里。 The quality of water is not excelled, and sanitary measures are in force to maintain the purity of the supply. There are two reservoirs connected with the system; a storage reservoir at Rush, about nine miles south of the centre of the city, and 224 feet above the general elevation thereof, having a capacity of 63,500,000 gallons; and a distributing reservoir, called Mount Hope reservoir, situated about two miles south, and about no feet above the general elevation of the city, with a capacity of 22.500,000 gallons. The potable water is brought to the city in two gravity conduits. One, completed in 1875, composed of thirty-six-inch wrought iron pipe, 9.62 miles, twenty-four-inch wrought iron pipe, 3.03 miles, and twenty-four inch cast iron pipe, 15.58 miles— total length, 28.23 miles. Its capacity is about 6,500,000 gallons a day. The second conduit, completed in 1814, is composed of a six-foot brick horseshoe-shaped tunnel, 2.25 miles, and a thirtyeight-inch, riveted, steel pipe, 26.19 miles—total length, 28.44 miles; daily capacity, about 16.500,000 gallons—making a total daily delivering capacity of both conduits of 23,000.000 gallons. Rochester is conspicuous for the care it has exercised as a municipality over the purity of its water supply. Hemlock lake has been particularly looked after, and now there are but few cottages remaining on the lake shore, whereby the number of sanitary pails has been reduced to 480, and the tedious, expensive and generally unsatisfactory method necessarily pursued in collecting these pails correspondingly lessened. In consequence, except for the occasional excels of organisms. which affect the smell and the taste, but not the wholesomeness of the water, the supply as furnished is perfectly uncontaminated with unsanitary elements. During the year the connections at Rush reservoir were inaugurated. The work consisted in the removal of the temporary sixteen-inch pipe which has conducted water from conduit II to the reservoir since 1893, extension of a twenty-four-inch pipe from conduit I to the bypass house, the placing of one twentyfour-inch and two thirty-inch gates in the bypass house, with the necessary pipes and special castings, the removal from the existing screen well of the old screens from the openings in the outer face of the wall, and the placing within the well of new screens of greater area identical with those in use at Mount Hone reservoir and Hemlock lake gatehouse. In addition to the above, a second screen well and weir chamber was constructed in the reservoir and surmounted hv a brick building with a tile roof. The substructure is of concrete, the floors reinforced with Kahn trussed bars. The building is reached from the bank by a concrete bridge. The measuring weir is a sharp crested overfall ten feet long placed in a smooth concrete channel ten feet wide, at a height of 4.60 feet above the bottom. The channel of approach is twenty feet long; the water enters at the bottom near the rear end: passes through two sets of stilling racks, and thence over the weir, the brass crest of which is adjustable vertically. Ample provision is made for the admission of air tinder the falling sheet of water. One-quarter-inch openings connected with a piezometer are drilled in a brass plate let in flush w’ith the side of the channel and six feet upstream from the W’eir. The crest of the weir is about two feet above the floor over the adjoining screen-well—making a convenient arrangement for observing the head upon the weir. The water is supplied to the weir through a thirty-inch pipe from the by-pass house, so arranged that the supply from either or both conduits can be measured. A thirty-six-inch pipe was constructed from the by-pass house through the well beneath the weirchamber, terminating in a vertical pipe with its top four and a half feet below high water in the reservoir. The screen-well, with screen area of sixty and a half square feet—the same as in the old screen-well—discharges into a thirty-six-inch pipe, which is connected with the pipe system in the by-pass house. An overflow, with spillway nine feet long, has been constructed with a sixteen-inch pipe outlet. This provides an element of safety, as it will preclude the possibility of an overflow of the reservoir banks. The entire substructure is built of imperishable material, no wood whatever being used. In the dry well below the spillway two six-inch cast iron pipes have been set vertically and connected by one-inch brass pipes to the overflow-chamber and to the chamber below the screens. Observation of the water surfaces in these pipes readily shows the elevation of water surface in the reservoir and the loss of head through the screens. The cost of this substructure, including all changes and additions in pipe connections, together with the overflow pipe and 0.44 acre of right of way therefor, was $16,395.15. The brick superstructure cost an additional $3,375. The reservoir was also thoroughly cleaned by the following method: Conduit 1 was shut off near the city and a blow-off opened between that point and Rush reservoir. Through this blow-off the lower stratum of water from Rush reservoir was wasted into a brook. The entire supply, of the city now passed to Mount Hope reservoir through conduit II. Gate No. 1 in the Rush by-pass house was kept throttled down, and the sixteen-inch pipe, which led from the bypass house to the top of the reservoir bank, was kept open, so that the water might rise and fall in it as a standpipe, and, in case of too great a head, overflow into Rush reservoir. A spring-gauge and a mercury gauge were attached to the conduit leading towards Mount Hope, and a spring-gauge was also attached just upstream from gate No. 1. By these means, together with the pressure-gauge at Mount Hope, a uniform pressure and a nearly constant discharge were maintained into Mount Hope reservoir through the fountain and thesubmerged inlet. To compensate for the varying demand in the use of water in the city, a blow-off was opened into the Genesee river at the McLean place pipe crossing. This gate was operated several times each week, and readily kept the depth of water in Mount Hope reservoir within ordinary limits. At Mount Hope reservoir was completed the superstructure of the new gatehouse, replacing the temporary structure erected over the stopgates in 1894. The building is twenty-eight feet by thirty-nine feet, and has an eight-foot terrace, with a granite parapet. It is highly ornamental and thoroughly appropriate to its situation in Highland park. Its total cost was $14,738.23. The total amount of pipe laid on the domestic system is 286.359 miles; on the Holly system, 19.922— total. 306.281 ; hydrants in streets—domestic system—2,186, Holly, 307. in private and public corporation grounds, 56, 6—total set in city, 3.185; stop-valves in distributing pipes and mains, domestic, 2,807. Holly, 280—total, 3,087; stop-valves in large service pipes, domestic. 147. Holly, 148— total, 345; sprinkling-cart cranes, domestic, thirty, Holly, twenty-two—total, fifty-two; drinking troughs for animals—all in domestic system, fiftyfive; meters in use, 12,260; average per-capita consumption, domestic, 78.45, Holly, 8.62—total. 8707 gallons; average consumption per dav in 1904, domestic. 13.720.775 gallons, Holly, 1.508,000—total. 15,237,773; total consumption for the year, 5,576,683,994 gallons—passed through meters, 1,979,551 gallons—thirty-seven per cent.; taps in use, 37,680; population (estimated), 175,000. During 1904 the following net additions were made to the two distributing systems: Domestic system—6.826 miles of pipe; 125 fire hydrants: 153 stop-valves; Holly system—0.029 miles of pipe; eleven fire hydrants; sixteen stop-valves. The large mains of the distributing system were extended during the year as follows: On the west side of the city, from Brown street through Kent street and Jay street to Smith street, with a thirty-six-inch pipe, and on the east side, from Central avenue to Herman street in Joseph avenue. with a thirty-inch pipe. The net cost of the works to December 31, 1904, was $8,791,348. The total revenue from all sources was $753,817.77; expenditures, including operation (management and repairs), $128,317.31 (and specials, $13,072.61). $141,389.92.
