WATER IMPROVEMENTS FOR ATLANTIC CITY

WATER IMPROVEMENTS FOR ATLANTIC CITY

On the left bank of the old Doughty Pond, about two miles back of Absecon, a spiderlegged structure rears its head above the surrounding treetops. At the foot of the embankment on which this structure stands stretches a barren waste of land filled with old tree stumps, underbrush and the deposited refuse of former floods. On the opposite bank of this waste land, fifteen hundred feet away, is another structure composed chiefly of enormous iron or steel wheels. In the course of a couple of weeks these two objects will be connected with twin steel cables of great strength and weight. These cables will be suspended between the two structures in a single span of 1,500 feet. Two steel buckets, capable of holding three wagon-loads of material each, will slide out on the cables and the work of converting the little Doughty Pond into a lake two hundred and fifty acres in extent will have begun. For the two structures on either side of the .pond, together with the cables, the buckets and machinery on the main tower constitute the new slack line excavator recently ordered by the Board of Commissioners to perfect the storage system of Atlantic City’s water supply. When the Board of Commissioners granted an appropriation of $200,000 for improvements to the water system it was thought that this amount would be about sufficient to build a dam at Doughty Pond so as to increase the storage capacity of the pond a few millions of gallons, to grub and thoroughly clean out the basin within which the impounding reservoir will be created, to install improvements at the pump wells at the pumping station and to purchase additional machinery at the station. It was estimated that the cost of grubbing and clearing the basin of the Doughty Pond would cost about $30,000, although when bids were opened for this operation it was discovered that the lowest was for $45,000 for this one item. When new bids were called for this item was omitted and the bid for the construction of the dam was $71,000 as against $151,000 for the entire operation. Then it was decided bv the engineers to have the clearing and grubbing done by day labor at an estimated cost of $30,000. With this object work was started at once. After digging to a depth of a few feet it was discovered that the material contained in the waste land back of the Doughty Pond was of such a nature as to absolutely preclude its handling bv human hands; that, beneath a shell of turf which was supported by the growth of trees, weeds and vegetable matter, was water and semi-liquid muck which could not be removed by an army of men in a dozen years. The engineers had not counted on being confronted with such a problem. Then Chief Engineer and Superintendent Lincoln Van Gilder, of the Bureau of Water, remembered a new kind of excavator that was adapted to the performance of such work as was presented by conditions in the Doughty basin. A halt was called on the work of clearing and grubbing the land by hand and an investigation was started. The makers of the slack line excavator were interviewed. Their machine, they declared, was adapted to the handling of just that kind of material. The manufacturers pointed to other places where the machine had performed identically the same kind of work. The manufacturers made the proposition that they would erect and operate the machine for thirty days without any obligations on the part of the city beyond the guarantee to purchase if the machine made good. Director Bacharach was convinced that they had found a way out of their dilemma and the Board of Commissioners unanimously adopted the same conclusion. So the offer of the manufacturers was accepted: It has been said that the method of operating this machine is simple. The main tower, which is of skeleton construction, but of massive timbers, is equipped with a powerful hoisting engine which operates the steel cables. The latter run through pulleys at the apex of the structure and on these cables are suspended the buckets, each with a capacity of three wagon-loads. What is called the tail tower is located on the opposite bank and the cables pass over grooved wheels with which the tail tower is equipped. All this machinery is controlled and operated by a single man located in the top of the main tower by a system of levers. One bucket is run out on one of the cables until it stands suspended over a point in the bog that is being attacked. The cable is then slackened (an operation that gives the machine its name) until the bucket scoops into the material that is to be removed. When filled, the cable is made taut and carries the bucket swiftly to the bank, where it is dumped and the bucket is ready for another trin. But while this bucket is returning with its load its companion is running out for a load, so there is a continuous performance by the two buckets. Both the main and the tail towers rest on massive trucks and these in turn rest on steel rails so that both towers can be moved along this track as the work progresses. In spite of the fact that the machine works with great rapiditv in the removal of eight hundred cubic yards of material a day it is estimated that it will take two years to completely clear the basin down to the sandy bottom, which is the result aimed at, because the amount of material to be excavated reaches the total of 750,000 cubic yards. But when this gravelly and sandy bottom is attained there will be no further danger of a recurrence of the rank growth of vegetable matter, the water will remain absolutely clear at all times and its temperature will be lower than at present. And these virtues will be secured in addition to an increase in the capacity of the reservoir from about twenty million gallons of water to about three hundred millions. To counteract the immense weight of the cables and buckets, as well as the loads carried by the scoops, a counter balance is arranged on the shore side of the base of the tower in the form of an enormous bin which will be filled with sand to the weight of 130 tons. This bin is attached to the base of the tower and the structure supporting it also runs on tracks. When Commissioner Bacharach was assigned to the Department of Parks and Public Property and the Bureau of Water was placed under his jurisdiction he immediately started an investigation of the city’s water supply with a view of extending it to take care of future needs. The first step was the laving of a new forty-eight-inch east iron force main across the meadows at a cost of $415,000. The distribution system in the upper part of the city was lacking in capacity, so a new main was installed in Arctic avenue. The two big meadow force mains insured the city a duplicate supply system and the distribution system was adequate, for the present, at least. Then came the question of the supply of water at its source, with especial reference to the storage of water. The city is virtually dependent on the upper and lower Doughty Ponds and the artesian wells for its supply, the Bargaintown Pond having been practically abandoned. The present capacity of the lower pond is about twenty million gallons and that of the upper pond fifty million gallons. These ponds were studied by Mr. Bacharach and his engineers with a view to increasing their capacity to the highest possible maximum. It was found that this could be done by increasing the height of the dams and it was decided to adopt this course, the first improvement being to the lower pond. Work on the reconstruction of this dam was started early in the year and will be completed in about two months. The finished length of the dam will be two thousand feet, the extreme height seventeen feet, the extreme bottom width sixty-five feet, the length of the spillway will be 110 feet and the height of the crest of the spillway above mean tide twelve feet. The dam is built of earth and sand above grade with interlocking steel sheet piling extending twenty feet below grade with a concrete core wall to the high water line. The water face of the dam is paved with concrete to prevent damage from wave wash. A concrete retaining wall has been built on the outside of the dam to protect the roadway from overflow a distance of three hundred feet. The spillway is of solid concrete. The steel sheet piling under the core wall and extending twenty feet into the ground is to prevent the blowing out of the dam by the water pressure on the sand foundation. When this dam is completed and the excavator has removed the bog to the sandy bottom the reservoir will have been increased from a capacity cf twenty million to three hundred million gallons—a supply sufficient for the needs of Atlantic City for generations to come. But this will not be all. When the lower pond has been completed it will be an easy and inexpensive matter to create another storage reservoir in the upper pond of even greater capacity. The excavator can be moved along on its track to a position opposite the upper pond and repeat the operation. When this has been accomplished the capacity of this pond will be increased from fifty million to two hundred million gallons, making a combined capacity of the two ponds of five hundred million gallons. The present daily pumpage is seven and a half million gallons. The maximum daily pumpage has been fourteen million gallons and the maximum rate of pumpage is seventeen million gallons per day. Having arranged for an ample supply, storage and distribution of water, Director Bacharach and Chief Engineer Van Gilder turned their attention to the subject of placing the pumping station in a modern condition to handle the sunplv and to eventually provide a complete duplicate system of water supply so that an accident to cither system would not interrupt ‘he delivery of a full supply to the city’s distribution mains. The capacity of either of the meadow mains is more than sufficient to meet all the requirements of the city, even in the height of the summer season. The pumping station is now equipped with two modern pumping engines, one of ten and one of twelve million gallons capacity; three old engines, two of throe million capacity and one of six. To bring the pumping capacity up to the highest point of efficiency and to provide for a duplicate system a new turbine engine with a pumping capacity of eighteen million gallons is now being constructed for the station. After re-arrangement of the pumps the total capacity will be fifty millions of gallons a day as against thirty-four millions at present. Other work at the station includes the construction of concrete conduits between the basins near the station and from the larger basin to No. 1 pump well; the deepening of No. 1 pump well end the construction of bypass and rcgulatifip chambers. These improvements will facilitate the present work at the station and are essential to the establishment of the duplicate system of water supply. It is now expected to perform all the work now outlined at an expenditure of $200,000, or within a few thousand dollars of it. Excluding the cost of dredging the reservoir, which will extend over a period of two ‘ears, the outlay will come far within the bond issue. The estimated costs are as follows: Dam and spillway, $75,000; clearing swamp by manual labor, $15,000; excavator, $21,000; conduits, basins, etc., at station, $20,000; eighteen million gallon pump. $15,000; total, $140,000. The estimated cost of dredging the reservoir is $60,000. The total value of the water system is estimated at the present time at $2,350,000, divided as follows; Outside the citv. $1,475,000; within the city limits, $875,000. The cast iron meadow main, which was provided for by previous bond issues, cost $415,000, and the wood stave main cost $315,000.

*Abstract reprinted from Atlantic City (N. J.) “Commission Government,” May, 1915.

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