Lithograph by A Brown & Co, showing the water main on the High Bridge over the Harlem River in New York City during construction. The rapid growth of New York City in the 19th century necesitated the construction of a network of reservoirs, dams and aqueducts to provide the city with an adequate supply of fresh water. Completed in 1848, the High Bridge formed part of the Croton Aqueduct, constructed to carry water from the Croton Reservoir to New York City. A new 90-inch diameter main was added to the bridge in 1860. The bridge was originally designed to resemble a Roman aqueduct and built with 15 stone arches, but in 1927 the central arches over the river were replaced with a single steel span to allow acces for larger ships.
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