History of Westchester County, New York, Vol. I
It is in contemplation by the city authorities to discontinue this bridge and King's Bridge, and erect either a tunnel or one large bridge at the upper end of Manhattan Island, but as yet the plans for this change are not perfected.
Between the Farmers' Bridge and the High Bridge commissioners are about erecting a new bridge, spanning the stream and extending from Aqueduct Avenue on the Westchester shore to the Tenth Avenue on the Manhattan Island aide. This bridge is to be built in pursuance of the Laws of 1885, and is to be a masonry structure with an arch spanning the entire channel of the river, over one hundred feet above high water-mark. The contract is about to be let.
The Croton Aqueduct or High Bridge. -- The high bridge which crosses the Harlem River at the northwest corner of Morrisania was built as an aqueduct to convey the water of the Croton River to the reservoirs of New York City. It spans the Harlem where that stream has a width of six hundred and twenty feet and its banks an elevation of one hundred feet. The original design of the engineers was to convey the conduit across the river by means of a stone embankment, broken by a high arch, through which the water would flow in a syphon, but the objections of the property-holders in the vicinity caused the bridge plan to be adopted. The aqueduct has tifteen arches, eight of which are on the river bottom. They are each eighty feet in width and one hundred feet high above flood tide. The seven shore arches have each fifty feet span. To reach the foundation of each pier a coffer-dam was built and pumped out until the sand bottom was excavated and the solid rock laid bare or a firm pile foundation prepared on which the masonry was laid.