新伦敦水厂系统
康涅狄格州新伦敦的供水系统建于1872年，从现任工程工程师J. T. Fanning的设计，W。H。Richards，正在建设工程师。供应量取自Kononoc湖，这是一个天然湖泊，由一座土坝抬高了十英尺，上面有瓦砾砌体核心墙。大坝是在一个非常危险的基础上建造的砖石覆盖和门户。没有尝试到达基岩或粘土基础；但是，作为预防措施，板块被驱动在大坝的上游脚趾上。Kononoc湖的流域占976英亩，此后已增加到1150英亩，存储容量为600,000.000加仑。供应是通过大约一英里的二十四英寸瓷砖管和16英寸锻铁水泥衬里管的数英里，到达城市的数英里。二十四英寸的瓷砖管在关节处发生了很大的泄漏，被i8> 8中的二十四英寸铸铁之一代替，而尚未使用的16英寸主在1890年与一盎司二十英寸的铸铁。在不久的将来，瓷砖和锻铁水泥衬里的管道都将配有更大的电源。 In 1901, the supply having become inadequate for the grow -ing city, a site was selected for a new reservoir three miles beyond lake Konomoc. This new reservoir, called Barns reservoir, was made by the erection of a dam across the valley of a brook, thereby flowing about forty-seven acres. The but this, being so light, broke frequently, and an ordinary pile-driver giving very light blows was substituted. The core-wall is located close to reservoir, as constructed, has a drainage area of 2.7 square miles, an area of 46.5 acres and a capacity of about 170,000,000 gallons, it being so arranged that any surplus can be stored in the Konomoc reservoir at a lower level. The immediate banks of the reservoir are gravel and sand, interspersed with granite boulders. A so-called filter dam is cut off from the main lake at the upper end of the basin. It consists of a hank of coarse gravi high and ten feet wide on the top, with slopes of 2 to r protected by loose rock. Though this dam is a twenty-four inch pipe and twenty-four-inch gate, and an overflow canal eighteen feet wide passes through round the north end. The main dam consists of an earthen embankment about 1,200 feet long, with a concrete core-wall. The embankment varies in height from ten feet to twentv-five feet above the natural surface. A supplementary dam, about 375 feet in length, is located 200 feet east of the main dam. Like the dam at lake Konomoc, this dam was built on very treacherous foundations. On excavating the corewall trench a pocket of fine sand was encountered from thirty-three to eighteen feet below the surface, running from a point 565 feet from the west end of the dam and terminating very abruptly at a distance of 375 feet. The core-wall is in places over forty feet deep and rests on four-inch grooved and splincd sheet piling, driven in the centre of the trench. This sheet-piling is driven to hard bottom, a maximum distance of twentytwo feet below the bottom of the core-wall trench, with heavy wale-pieces bolted along the top, on which the footing course of the core-wall is built. Driving this sheeting at the bottom of so deep a trench was a delicate operation. At first a steam rock-drill, with a light hammer, was used, the inner slope of the dam, and the greatest care was taken to make it impervious, and, as no dependence was placed on it to resist strains or add weight to the dam, it was made but three feet thick up to within eighteen feet of the top, where it begins to batter to eighteen inches thick at the top. I be concrete, which was composed of one part of Portland cement to nine of gravel and sand, was mixed very wet, and built up in layers of about two to three feet, a triangular form being placed in the centre of the top of each layer to form a groove with the next layer. The embankment on the outside of the wall is of sand and gravel, the finer material being placed next the core-wall and puddled the coarse material outel above 400 feet long, twenty feet side this. The front embankn icnt is of loam tlior oughly rolled, no clay being available. The in side paving is of twelve-inch paving; the slopes are 2 to t inside and 1½ to 1 outside. There is a granite spillway at the east end and low’er part of the dam. It is forty feet wide—15.8 feet for every square mile of watershed. The water falls with a perpendicular drop of three feet and runs down a paved slope of 12 in 100 into the brook below the dam. The gate-chamber, which is about 950 feet from the west end of the dam, where it is twenty-eight feet high, is seven feet by four in section, and 27.8 feet below the gatehouse. Large stones were placed in the concrete as built up, averaging a foot thick at the top, with a batter of one inch to the foot. Water is admitted to the chamber through two twenty-fourinch sluice gates, located eight feet and 11.3 feet above the bottom. Cast iron jambs for two sets of screen frames are set in the chamber. The discharge from the chamber is through a twentyfour-inch heavy cast iron pipe, this pipe also serving as a blow-off through a branch to the old brook bed. The level of the bottom of the elflu ent pipe is 187 feet and the crest ot the spillway 210 feet above mean high tide. The gatehouse is nine bv eleven feet. It is built of cobblestones and has a slate roof. After leaving the dam, the size of pipe is reduced to sixteen-inch and continues this size for 6,791 feet, where it is increased to twenty-inch and continues this size to the head of lake Konomoc. This increase in size is made to provide for the discharge from another reservoir which may be built on the Bogue brook in the future. A low dam on Mountain brook can also be arranged to divert the water from a large watershed into lake Konomoc through this main. The entire main is three miles long, and is divided into two sections by gates and has the usual blow-off and air-valves. The sides of the reservoir were thoroughly cleaned of soil and roots and the bed covered with fine gravel. Its capacity of 170.000.000 gallons, with lake Konomoc. makes the total storage capacity of the works 770,000,000 gallons, and the total watershed 4-5 square miles. 1 he distribution mains which were originally of wrought iron cement-lined pipe, have been nearly all renewed with cast iron. In 1890 it became desirable to increase the pressure on the higher portions of the city, and a watermotor or engine was installed, w hich pumps water into an elevated tank. This motor is somewhat unique, being actuated by the passage of water through the supply main to the lower part of the city’. It drives a pump, which elevates water into a wrought iron tank, 213 feet above datum—thirty-five feet above lake Konomoc. the source of supply. | he capacity of the tank is 90,000 galions; it is twenty-five feet in diameter and twenty-six feet high and is supported on lattice girder posts sixty-eight and a half feet high. This device is still in service. The city’s extension was to still higher ground, and a second high service was built in 1903. It consists of a concrete-lined reservoir, built up in layers and blocks—the first layer being six inches in thickness and composed of concrete mixed into proportions of one of Portland cement, seven of sand and stone. The second layer was four inches in thickness, the concrete being composed of one Portland cement and five of sand and stone, the surface being finished smooth. The reservoir measures sixty-nine feet square at the bottom and 105 icet at the top. It is twelve feet deep and is designed to hold ten feet of water. At that depth its capacity is 545 gallons. ‘l’he elevation of the flow-line is 253 feet above mean high tide—seven feet higher than lake Konomoc and forty feet higher than the elevated tank on high-service No. 1. Water is pumped directly from the mains into this reservoir by waterpower furnished by Felton wheels under a head of 128 feet, the water being derived from a reservoir originally built to supply water for manufacturing. The pumping plant consists of a No. 1 Root rotary pump actuated by a twenty-four-inch Felton motor coupled together with a Reynolds silent chain, and a seven-inch by eight-inch Stillwell-Brice triplex pump geared to a thirty-inch motor. The triplex pump can also lie belted to an electric motor. A gate-chamber of concrete, six feet by thirteen feet, with vaulted roof and flight of steps leading to the top of the embankment is built into the easterly side of the reservoir. Through this chamber and into the reservoir passes a ten-inch inlet and outlet pipe, with a check-valve and upright supply over-flow pipe so arranged that, when the pumps are running, the head against the pump is constant, and, when the reservoir is full, water will flow into a six-inch pipe that will eventually be connected with low-service at Saltonstall>—A ten-inch forcemain starts from the pump house and extends to the reservoir. The pump house is supplied with a recording gauge and with a Venturi manometer. At the junction of Cole and North Main streets a Ross reducing valve has been installed, which reduces the pressure between the high-service No. 1 and high-service No. 2 about twenty pounds, so as to prevent the water overflowing the elevated tank on high-service No. 2, and to enable the cement-lined pipe on the low-service to withstand the pressure. The reservoir consists of an earthen embankment, eleven feet wide on top and sloping inside and outside 1/2 to 1. The embankment is of the very best clay, thoroughly sprinkled and rolled in layers. The formation Was such that very little excavation was required for the foundation, as, after removing about three feet of the top soil, an impervious hardpan was oncountered. Another reservoir of the same type may be built adjoining the present one. The cost of the entire work to date has been $1,003,017.23, the bonded indebtedness being $(>01,000. the balance having been paid from receipts. At New London all water for public uses is supplied without charge, and the receipts now amount to $67,528.26. The works have up to the present time been constructed by a non-partisan board of five members, who have continued in office for long periods, and to this is largely attributed the fact that the works are a source of profit to the city.
校长W. H. Richards。
校长W. 11.新伦敦下水道和水务部的工程师理查兹（Richards）是该城市的本地人。他上了普通学校和巴特利特高中，然后在著名的液压工程师J. K. Fanning的领导下对土木工程进行了研究。他于1871年开始对他故乡的水工厂进行初步调查，被任命为建设工程师，并在完成工作后被选为校长，后者的职位使他满意。On the organisation of the sewer department in 1886 Mr. Richards was elected engineer for the board of sewer commissioners, and the entire sewer system has been designed and built under his supervision.他的工作是一个高级的，他克服困难的方法如此巧妙，以至于他们引起了这个国家和国外著名工程师的关注和好评。高服务系统。谷仓水库，排水沟和河滨水库都是为他作为工程师的技能作证的作品。理查兹先生是新英格兰水厂协会的成员，并且是其杂志的多年编辑。他还是波士顿土木工程师学会和康涅狄格州土木工程师学会的成员。他是一位准备好的作家，表达自己，简洁地表达自己，是一个个性强壮的人。 He tills to the satisfaction of all, one of the most responsible positions in the gift of the municipality.
