as a stone viaduct for the aqueduct to Manhattan built in 1848 at the Canalization of 1937 the river piers were removed and replaced with steel arches with large span<br><br>In the thirties of the 19th century, there were large drinking water problems in Manhattan. So was begun in 1837 a dam at the Croton River (North of NYC). The water ran underground for the most part by large pipelines. But, the major natural barrier of the harlem River had to be bridged with a large stone viaduct. This 2 water pipes were laid, a third was added in 1864. The bridge was originally a pure stone viaduct with 15 arches, with the expansion of the harlem River 1939 the pillars standing in the water have been replaced by a large steel arch. The water of the Croton aqueduct was to the receiving reservoir fed, where today in Central Park, the big Lake serves as a reservoir and thence to a distribution reservoir of the 42th Street (site of the current Museum). This distribution building was square, and consisted of very thick walls, the resemblance to a Fort was unmistakable).<br><br>An old tower which was used as a gate-house for the monitoring of the are is on the West side.