THE DANVILLE WATER WORKS SYSTEM
Special Report of FIRE AND WATER ENGINEERING
The long-drawn-out controversy between the city of Danville, Va., and the Dan River Power and Manufacturing company, which owns the riparian rights above Danville, having been finally settled on terms agreeable to both parties, the Power company has erected a magnificent plant, including a large waterpower development, and is now running without inconvenience to itself or injury to the city’s water supply. The city, on its side, has built a fire-pumping station, with up-to-date pumping machinery installed therein. The new building and filter station are situated close to the Dan river, some 1,800 ft. above the new dam, the erection of which was one of the chief causes of the trouble between the city and the Power company. The station, which is architecturally an ornament to Danville, is 145 ft. long by 49 wide. Its concrete foundations are on rock-bottom 17 ft. down. The walls, ao ft. high, are of hardbttrned select red brick and support a roof of select heavy heart-pine timbers resting on iron trusses, and covered with slate, the ridges being of copper and the gutters and downspouts of galvanised iron. The smokestack is 135 fthigh and 5 ft. in diameter, with cast covering and a regulation lightning rod arrangement. It stands apart from the building. The boilerroom is 30×46 ft. and is separated from the pumproom by a 12-in. brick wall, in which is a connecting door. In it are installed two 150horsepower return tubular boilers, each 60 ins. wide and 18 ft. long, with seventy-four inch tubes, space being left for a third boiler. At present each boiler will be used alternately. The floor of this room is granolithic. The pumproom is 49×40 ft., and in it is placed the large horizontal, cross-compound, crank and flywheel, high-duty Snow pumping engine, whose capacity at slow speed is 3,000,000 gals. It has fully met its requirements—126000,000 ft. lbs. to every 1.000 lbs. of dry steam consumed. The pumping engine stands in a solid concrete foundation. In addition, there is a Snow compound-duplex pump ing engine, with a capacity of 1,000,000 gals., which is to be used only in an emergency. The city’s pumping capacity is now four times as great as is its present consumption of water. In the pumproom is also placed a small Ajax en gine, which furnishes the power necessary for running the machinery used in the operation of the filters. The pumproom has its walls in white enamel finish. In a conspicuous place on the wall a marble tablet has been placed, which bears a suitable inscription and the names of tintwo committees of the council who have had charge of this department. Adjoining the boiler room in a space 59×46 ft. is the filter-equipment, including all pipe-connections and valves. There are four filter-units of 500,000 gals, capacity in twenty-four hours making a total daily capacity of 2,000,000 gals, of filtered water when the water in the river is at its worst. Each of these four units consists of a cypress tank 8 ft. high and 15 ft. in diameter, which contains the copper, screws, manifolds, agitating device, and all other mechanical parts necessary for the operation of the filters together with a layer of sand 36 ins. deep. Immediately under the iilterroom is the clear-water receiving basin, which is constructed entirely of cement and has a capacity of 200,000 gals. Immediately over the filter-tubs, in the roof, is located the coagulating equipment, composed of two iron tanks for lime, two wooden tanks for sulphate of alumina, a compressed air plant and necessary piping connections. Immediately to the rear of and adjoining the filterhouse is the settling basin. This basin is 158.x50x11 ft. The walls are of concrete and have a maximum thickness at the bottom of 15 ft. Its capacity, when ftdl to the level of the dam, is 500,000 gals., and it is equiped with inlet and outlet valves, controlcrs, etc. The water is taken from the intake crib (located in the pond above the dam) and conveyed through a 24-in. cast iron main to the settling basin. Just before entering this basin, the coagulant will he applied, and, after several hours settling, it will he admitted to the filters. While passing through the sand, it will arrest all coagulated matter and the water will be delivered thence into the clear-water receiving basin bright and sparkling as a mountain stream, and with a guaranteed reduction of bacteria of ninety-eight per cent. From the clearwater basin the water will be pumped to the reservoir in Ballou Park and distributed to the city by gravity, as at present. All the piping in connection with the pump is covered with Sarly’s eighty-five per cent, magnesia covering. The Pittsburg Filter Manufacturing company, of Pittsburg, Pa., was awarded the contract for the gravity filter, the estimate for which was made by Frank Talbott, the city’s superintendent of water, gas and electric lights, wdiose practical experience of fifteen years in that department rendered him in every way fit for the task. The total cost of the improvements came well within the $98,000 appropriation. An engineer’s ing station. The filter plant was erected under the immediate supervision of David Davis, of Pittsburg; the boilers were furnished by the E. Keeler company, of Williamsport, Pa.; and the settling-basin, dear-water well, and brick pumphouse—a frame building stands near the pumping filter station complete, with smokestack byGeorge B. Hinman, of Atlanta, Ga. The concrete intake crib in the pond was constructed by Charles Orchard, of Danville. Laying the cast iron pipe-line (some of the pipe weighing 2,400 lbs. to the length) was a work of no small difficulty. Two thousand feet of 24-in. and 3,800 ft. of 16-in. had to be laid either in very treacherous ground or in rock w’hich had to be blasted out 20 ft. under ground. The whole work was done under the direct supervision of City Engineer J. O. Magruder and Superintendent Frank Talbott. The average bacteriological efficiency of the filter plant is 99.9 per cent.—the lowest being 995Filtered water was pumped into the reservoir for the first time on July 7. 1905. and since that time up to April 30, 1906, there were filtered 216,789,741 gals.. 6.652 lbs. of lime and 41,353 lbs. of sulphate of alumina—an average of one grain and one-third being used as a coagulant. During the entire time the city has had water perfectly clear and unusually pleasant to the taste. From time to time samples were taken from spigots down in the business sections of the city and sent on by disinterested parties for analysis. In every case the report has been that there was absolutely no trace of alum in the water and nothing injurious either to the human system or to the inside of steam-boilers. Under direction of the president of Danville’s board of health, samples have been sent to the University of Virginia and other sanitary experts for bacteriological examination. The reports thereupon have been eminently gratifying, showing the water to be in all respects satisfactory. During the fiscal year ending on April 30, 1906, were pumped 274,961.963 gals. (41.015,353 by the old pump from May 1, 1905, to June 14, 1905)—a decrease of 42,021,514 from the pumpage of the preceding year. The average daily consumption, including Sundavs, was 753.320 gals.—an average daily per-capita consumption of forty-four gals, based on a population of 17.000—274 gals, being discharged by the new pump nto the reservoir for every pound of coal consumed. With the old pump, it was only 147 gals.—a saving of eighty-six per cent.—the employes pumping only eight and one-third hours instead of seventeen hours per day. The consumers now number 2,240. Four hundred and sixty-one hydrants are set, and there are 2488 meters in service—a net gain of 232 meters during the year. The number of taps made during 1905-06 was 201—the largest in any like period of time. 1 he meterage system was inaugurated in July 1, 1892; hy the end of 1893 all the existing taps were metered and now every tap in the city is metered. In Superintendent i-rank 1 albott the city’s waterworks cepartment possesses an official who knows to combine both efficiency and economy.