Engineering Wonders of the World
Volume III

THE WATER SUPPLY OF NEW YORK CITY. 105 York with a daily supply of 500,000,000 gallons. The engineers, however, mindful of the dim and distant future when the city may demand a second aqueduct, have decided that the gate chamber, where the water sup- ply from the reservoir will be controlled, shall have a capacity for handling daily no less than 1,200,000,000 gallons ! The Asho- kan Reservoir is divided naturally into two basins, one in the valley of the Esopus, and the other in that of the Beaver Kill; and this sepa- ration will be completed by the construc- tion of a weir and dike, each 1,100 feet long. Over the weir, which will be built of mas- onry, will pass, under certain c o n d i t i ons, flood water from the west to the east basin en route to the waste weir. This latter will be a masonry structure 1,000 feet long. The Beaver Kill dikes, in the aggre- gate 2’3 miles long, will rise about 110 feet above the original surface, and have a maxi- SITE OF OLIVE BRIDGE DAM. The two huge 8 feet diameter steel pipes will carry off the water of the Esopus Creek during the construction of the Dam over them. {Photo, by courtesy of the “Scientific American." mum width at the bottom of 650 feet. They will be built with concrete core-walls, and, with the dividing dike, will require in construction about 180,000 cubic yards of masonry and 5,000,000 cubic yards of other material. Little less im- pressive than the New Cro- ton Dam will be that built across Esopus Creek. Its cen- tral mass, of concrete mas- onry, will be 1,000 feet long, 200 feet wide at the base, and have an extreme height of 240 feet from crest to bottom of the cut-off wall. Each end of the masonry- will be flanked by an earthen wing about 1,800 feet long, with a maxi- mum width at the base of 800 feet, and a top width of 34 feet. Core- walls of con- crete, founded on rock, will be built into each of these wings. For the central portion of the struc- ture there will be required _ Bridge Dam. about 550,000 cubic yards of masonry, and for the wings about 2,000,000