THE CROTON WATERSHED

THE CROTON WATERSHED

The Croton watershed, which is to furnish the new Croton reservoir with 30,000,000,000,000 gallons of water for the supply of New York city, abounds in streams whose waters are now running to waste. From Croton Landing up to the dam is a large colony of Italians, the population of which is reckoned by the thousand, and, with their dwellings, is dominated by the dam—a massive wall extending across the valley for nearly half a mile. It is over 300 feet high, half of which is beneath the river bottom, over 200 feet thick at the foundation, and 2,200 feet long. From a width of over 200 feet on bottom it batters in rapidly to a width of one-tenth as much as its top, where it is only twenty-two feet wide. The dam, as originally designed, was made up of three sections, at the south end for 400 feet a high earth bank, in the centre of which was a core of masonry. Adjoining this, for 600 feet, is the main body of the dam, built entirely of masonry. At its north end is the spillway, the top of which is twenty feet below the top of the other portions. About two years ago it was decided as being safer, instead of the embankment and core wall at the south end, to continue the main body of masonry into the side hill. This change involved tne tearing out of the work already done in that section and replacing it with new work at a cost of about $500,000; but the additional security obtained in a structure of such magnitude, which will govern the entire water supply of Manhattan and the Bronx, more than justified the expenditure. The body of the dam is pierced by two archways, one for the outlet of the river and the other for train connection between the two sides. These, of course, will be filled in when the dam is finished. Three heavy fortv-eight-inch pipes pierce the dam across, forming additional wasteways, which are controled by gates from the house above them. At the south end another gate-house will control the flow of the water into the aqueduct. At the junction of the main body of the dam with the overflow a guard wall is built ten feet wide, containing in its interior a winding staircase to the top of the dam. At several points this staircase leads out to platforms, from which magnificent views of the Croton valley may be had. The waste waters will fall down the 130 feet of stone steps on the lower side of the overflow. Before any masonry was laid, an excavation 1,000 feet wide on top and over 200 feet on bottom, extending across the valley, had to be made, and out of this excavation 2,000,000 cubic yards of earth were taken. Enormous quantities of rock had also to be taken out of the hillside to provide an adequate channel for the river water. Over 5,000,000 cubic yards of masonry must be laid before its completion. A large amount of earth which had been removed to make room for the masonry has to be replaced. Upon the completion of the dam and on the filling of the present reservoir, the water will rise about thirty-five feet above the water in the present Croton lake, before it will waste over the spillway. The new lake thus formed will extend east for fifteen miles. Crossing under the Harlem River railroad near Katonah and turning sharply north three-quarters of a mile west of Katonah, it will extend up above Croton Falls, a distance of nearly twenty miles. The rising of the lake for thirty-five feet will flood over twenty-five miles of the present roads and about 3,000 acres of land, all of which had to be purchased by condemnation. Besides the difficulties in constructing the dam itself, the aqueduct commission and the engineers who had this work in charge have had to replace these flooded roads by new ones at a cost of nearly $1,000,000. The old Croton dam, about two and a half miles east of the big dam, which for over sixty years has done duty for the city will be entirely submerged to a depth of some thirty or thirty-five feet. A drive of four miles along the banks of the Croton lake shows what is being done for the completion of the work in the way of new roads, bridges, and the like on the land vacated for the purpose under condemnation proceedings. Near the junction of the Croton and Muscot rivers, about a mile west of Katonah, the Muscoot dam is being built. While this is of the same general type as the new Croton dam, it is comparatively small in size, and cost only $250,000. The lake formed by this dam will extend north over five miles. The spring floods have caused some trouble during its construction. A heavy rain falling on frozen snow-clad ground will in a short time swell the rivers to an enormous extent, every insignificant stream becoming a torrent. In these days of heavy flood, the Croton river, forced to empty itself through the tunnel in the big dam, does so with an impetuous velocity, the foaming, furious rush of the water giving but a faint impression of the power stored up behind it. The flooding’ of the valley has caused hundreds of people in the eastern portion of what will be the new reservoir to be evicted. Houses that have stood for generations, schools, churches, hotels, even cemeteries, all have to go to make room for the new lake. Entire villages have been razed and removed. Especially has this been the case with the old village of Katonah, forty-one miles from the city, on the Harlem railroad. A new one has been built farther up. Within a radius of half a mile from this village no less than six bridges must be built to carry the new roads across the various streams and railroad tracks. Turning north at Katonah there arc nearly seven miles to drive before reaching Croton Falls, the northern extremity of the city property, at the dividing line of Westchester and Putnam counties. Along here various kinds of work are also in progress. Surrounding the entire property purchased by the city over forty miles of stone wall fences are to be built. These walls, if built in a straight line, would extend almost from New York to Peckskill.

FACE OF NEW CROTON DAM AND A PORTION OF THE GREAT SPILLWAY.THE NEW CROTON DAM, AS IT WILL BE WHEN FINISHED.

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