THE INDIAN CREEK WATER SUPPLY

THE INDIAN CREEK WATER SUPPLY

The Pennsylvania Railroad company has established for its own use several water supply systems. One is at Indian Creek. Lafayette county, Pa., and is a stream that is free from coal-dust contamination. Its drainage-area is about 109 sq. miles, and the population upon it is very sparse—at most twenty-five persons to each square mile. At a point on the creek where the elevation above tide-level is 1,250 ft. a reservoir of 231,000,000-gal. capacity has been constructed, from which is laid a 36-in. pipe close along the stream to Indian Creek village, where it deflects northwardly till it reaches Gibson Junction, where there has been built, at an elevation of 1,222 ft., a distributing reservoir of 6,000,000gal. capacity. About 2 miles north of Conncllsville this 36-in. pipe meets the southwestern division of the Pennsylvania railway which it follows in a northerly direction to Hawkeyc, where another reservoir of 13,000.000-gal. capacity has been built, at an elevation of 1.200 ft. Here the pipe-line becomes 30-in. to Radebaugh. At Youngwood, about half a mile from the line, and connected with it, is a distributing reservoir of 1,000,000-gal. capacity, to supply the southwestern division of the road. At Radebaugh has been constructed an 8,500,000-gal. distributing reservoir, and the pipe-line runs west along the main line to Pitcairn, where there is a steel standpipe 100 ft. in diameter and 30 ft. in height. At Pitcairn the pipe, now reduced to 24-in., runs west to Port Perry Branch junction, where a 20-in. line is carried across the Monongahela river to Thompson, whence a 12 in. line runs west to Howard, where is a distributing reservoir, built at an elevation of 887 ft. The pipeline, now 12-in., continues to run south along the Monongahela division to Redstone Junction, thence by a 20 in. line, along the southwest division to near Gibson Junction reservoir—ntak ing a complete circuit. On the last two divisions were connected with the pipe lines the following reservoirs; The Gist, at Mt. Braddock, capacity, 2,800,000 gal. : the Smock, 2,000,000-gal. distributing; near Charleroi, one of 7,235,000-gal. capacity ; the l’.lhen, of 2,000,000-gal. capacity. A 12-in. branch runs from Redstone junction, by way of Uniontown, to Rainey, where is built a 2,000,000-gal. reservoir at an elevation of 1,102 ft. The storage at the Indian Creek reservoir in the driest season is up to 15.000.000 gal. in twenty-four hours. The dam is solidly built on bed sandstone rock. Its maximum height is 30 ft,; its length, 7(13 ft. The upstream and downstream falls are ol large rubble masonry, with horizontal and vertical joints and rock faces. Between these faces is 1 ; 2: 5 Portland cement concrete, with as large a proportion of stones, each of an average size id half a yard imbedded in it. It has a sandstone coping 1⅛ ft. thick. Laying the 36-in. line between Indian Creek dam and Conncllsville was a work of great difficulty on account of the precipitous mountain heights and landscapes. Below the line, therefore, a number of rubble masonry retaining walls bedded on solid rock were built, and where slides seemed likely to occur the pine was laid on the solid rock ledge, which at times had to be excavated to a depth of 30 ft. From Conncllsville the pipe was laid chiefly on the Pennsylvania road’s right of way. At Radebaugh a tunnel 2,too ft. long was built, so as to keep below the hydraulic grade. It was circular in section and had a 12-in. concrete lining, in which the 30-in. cast iron pipe was laid. Deep cuts, mine-openings, creek-crossings and difficulties in passing through towns had to be encountered, and in crossing streams into which mines drained the pipe had to be laid in and surrounded by concrete, to guard against corrosion. At Port Perry the 20-in. pipe was laid across the Monongahela river on structural steel brackets bolted to the outside of the bridge structure. The pipe was of steel, with flanged joints and was covered with 3 in. of hair felt. The bridge was over 1,000 ft. in length; but no expansion joints were put in. the tensile strength of the pipe itself and its joints being sufficient to take care of the stresses —the maximum being 20,000-lb. per sq. in. At West Brownsville, on the Monongahela division, the 12-in. pipe was laid below the bed of the river, the joints being of the flexible type. Under the Youghiogeuy Yiver. between Conncllsville and Wheeler the 20 in. pipe was laid in the usual way by means of cofferdams. For the Gibson

Junction reservoir the only place where it could he built was unsuitable because of the unstable foundation and unlit for earth enbankment, being shaley sandstone rock, with a surface sloping at a grade of ten per cent. A heavy rock excavation was, therefore, made on the high side and sufficient at the low side of the reservoir to secure a firm footing for walls of concrete masonry, with a top thickness of 3 ft., the vertical face against the water and back slopes of 1 to 4. T he concrete was 1:3:5 Portland cement, and in it were used reinforcing Johnson bars. The excavation was carried much wider on the high side than the neat line of the outside of the wall, thus admitting of a pipe-drainage system and rendering it unnecessary for the wall to act as a dam, if the reservoir were emptied. A cement coping 8 in. thick, projecting 2 in. towards the reservoir topped the wall, and on the outside of where the wall projected above the natural surface of the ground an embankment was formed from the excavated material. The width of the top was to ft.; the outer slope, which, with a portion of the top was sown with grass seed, being 1 1/2 to 1. In order that waterhammers might not injure the first 13 miles of 36-in. line, a 20-in. connection was made in the immediate neighborhood of the Gibson Junction reservoir, and the 20-in. pipe was run for a distance of 500 ‘ft. at the side hill, to a masonry chamber of small size, from which a second 30-in. terra-cotta pipe was laid back and was to overflow into the reservoir about a foot below the water’s surface—the elevation of the bottom of the 20-in. pipe being slightly higher than the flow-line in Indian Creek reservoir. This not very expensive and simple device proved thoroughly effective. The distribution reservoirs are of two types. In the first they are formed by an earthen dam, with a top width of 12 ft. and outer and inner slopes 1 ½ to 1, A puddletrench 6 ft. wide is sunk down to impervious material at the foot of the upstream slope. Two feet of concrete fill the upstream portion of the trench; 4 ft. of concrete, with thin layers of compacted clay incorporated at the top with the rolled embankment fill the downstream slope. A concrete connection is then made with the 12-in. normal thickness of slope concrete, and laid to within 3 ft. of the flow-line, and front that point is laid to 2 ft. of the flow-line an 18in. masonry slope wall. An earthen embankment. with a 12-in. concrete lining on the water side, the outer slope being either sodded or seeded, forms the second type of reservoir. Its bottom is covered with 16 in. of thin layers of compacted clay, overlain with 3 in. of concrete connected with the concrete. In both cases the slope is kept at least 3 ft. below the top of the embankment. Automatic controling valves are provided on the inlet-main so as to keep the reservoirs full and prevent overflow. O11 each outlet-main, also, is provided a large screen pot of -in.-mesli wire. The gatehouses are all of one type, with walls of broken range masonry, with 12-in and 6-in. rock-face stones laid with vertical and horizontal joints and regular alternate pattern, red roof-tiles and all-concrete floors on steel 1-beant construction. Large relief-valves, with either 6-in. or 8-in. openings, are provided near all the points of construction on the distributing system of pipes, as are, also, many of the railway water tanks, there being the supply-pipe within the tank. Venturi meters are also provided at several points along the supply pipes. The total length of pipe on this system is as follows : Thirty-six inch, 17.06 miles; 30-in., 32.17 miles; 24-in., 3.29 miles; 20-in., 7.74 miles; 16-in., 4.42 miles; 12-in., 66.30 miles: 10-in., 4.27 miles— total. 135.25 miles. The total capacity of the twelve reservoirs is 283,465,000 gal.

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