The High Bridge (originally the Aqueduct Bridge) is a steel arch bridge connecting Manhattan and the Bronx in New York City, New York, United States. Rising over the Harlem River, it is the city's oldest major bridge, having opened as part of the Croton Aqueduct in 1848. The eastern end is located in the Highbridge section of the Bronx, near the intersection of University Avenue and 170th Street, and the western end is located in Highbridge Park in Manhattan, near the intersection of Amsterdam Avenue and 172nd Street. Operated and maintained by the New York City Department of Parks and Recreation, the bridge is a New York City designated landmark and is listed on the National Register of Historic Places.
The High Bridge, measuring long, spans a valley that contains the Harlem River. The original bridge had fifteen stone round arches, each measuring either long. The five arches over the Harlem River were replaced by a single steel arch between 1926 and 1928. The bridge originally carried water pipes, and gatehouses at both ends controlled the flow of water in these pipes. In addition, the High Bridge Water Tower (which is still extant) pumped water to the Highbridge Reservoir at the Manhattan end.
The High Bridge was proposed in 1839 in lieu of a low-level bridge or a tunnel carrying water across the Harlem River, and water began flowing across the bridge in May 1848. The bridge originally carried two water tubes; a third tube and a walkway were added in the early 1860s. The bridge was proposed for demolition in the 1910s and 1920s, as it posed a hazard to navigation on the Harlem River. The city government approved the demolition in 1923 before instead ratifying a separate proposal to reconstruct only the central arch. Water stopped flowing across the bridge in 1958, and the bridge was closed to all traffic by the early 1970s due to safety concerns. A restoration began in 2013, following several years of planning, and the bridge was reopened to pedestrians and bicycles on June 9, 2015.
Site
The High Bridge is an arch bridge between Manhattan and the Bronx in New York City, New York, U.S.. It carries pedestrians, bicycles, and the Old Croton Aqueduct over the Harlem River. The valley floor (which includes the riverbed) is made of Inwood marble, which erodes more easily than either the Manhattan schist on the Manhattan side or the Fordham gneiss on the Bronx side. The river measures about wide at this location. Approximately north is the Washington Bridge, and between the two spans is the newer Alexander Hamilton Bridge. East of the river, the bridge crosses the Metro-North Railroad's Hudson Line, the Major Deegan Expressway (carrying Interstate 87), and Sedgwick Avenue. The bridge's walkway continues east to University Avenue and 170th Street in Highbridge. the staircase is divided into staggered flights, rising over a run of . and is sometimes cited as the city's oldest extant bridge of any kind. and it was the last bridge constructed across the Harlem River before the Bronx was annexed into New York City in 1874. The High Bridge was originally part of the Old Croton Aqueduct, which carried water from the Croton River watershed to supply the then-burgeoning city of New York (now part of Manhattan). or above the Harlem River, with a total length of .
The design was led by Croton Aqueduct engineer John B. Jervis, who replaced David Bates Douglass, the aqueduct's original engineer. James Renwick Jr., who went on to design St. Patrick's Cathedral in Midtown Manhattan, participated in the design.
Arches
The bridge was constructed with fifteen semicircular arches. The design bears similarities to ancient Roman aqueducts; The wide arches, most of which have been replaced, originally spanned the river; the narrow arches, which still exist, spanned the shoreline on either side.
The arches are supported by piers measuring across at ground level. There were originally ten piers on the shoreline (including the abutments at either end) and six within the river. The mid-river piers were built on mud; The springers—where the lowest sections of the arches curve outward from the piers—are placed about above mean high water.
Due to the fast-moving waters of the Harlem River, the piers in the middle of the river originally created a navigational hazard, as watercraft were vulnerable to crashing into them. The piers did not run perpendicularly to the river channel, which meant that many barges had less than of horizontal clearance when passing through the arches. The arches are illuminated at night by LEDs. and a earthen embankment surrounded the tubes to protect them from extreme temperatures. Measuring about in diameter,