In an era before flight corridors, interstates, and railroads, the Delaware and Hudson Canal was one of many manmade waterways dug in 19th century America to connect the fledging country’s coastal cities to its raw materials in the interior. The D&H Canal, which linked New York City to the coal fields of northeastern Pennsylvania, took three years to dig and opened in 1828.
The journey was arduous. Mules dragged canal boats down the 108-mile-long tow path and had to pass through 108 locks as the elevation rose 1,075 feet. Dams originally were built where the canal crossed Rondout Creek and the Lackawaxen, Delaware, Neversink rivers. At these dams the mules and their drivers crossed on a rope ferry. Traffic jams plagued those four crossings, so in the 1840s the D&H Canal Company hired engineer John Augustus Roebling, fresh off his designs for two wire cable suspension bridges in Pittsburgh, to design aqueducts over the four waterways.
Completed in 1847, the wire cable suspension bridge over the Delaware River, known as the Delaware Aqueduct, consisted of four spans of a 134 feet each that ties Minisink Ford, New York, to Lackawaxen, Pennsylvania. The four stone piers were shaped like a V where they face upriver in order to break up ice floes before they smashed into the bridge. The wooden superstructure on top had a trough in the middle to hold the canal’s water and towpaths along the rim on both sides where the mules and drives walked. The canal operated until 1898. Shortly thereafter, water was drained from the aqueduct, and it was converted into a toll bridge first for wagons and then automobiles.
The bridge looked nothing like Roebling’s design by the time the National Park Service purchased the span in 1980. No longer needed to hold water, the trunk walls had long since been removed, and flimsy wood guardrails stood in their place. The stone piers and cable suspension’s remained, however.
The NPS undertook a restoration of the bridge’s superstructure in the 1980s and 1990s to return it to its original appearance while remaining a vehicular bridge. Of the four aqueducts that Roebling designed for the Delaware and Hudson Canal, the Delaware Aqueduct is the only still in existence. It’s also the oldest wire cable suspension bridge in the United States and a National Civil Engineering Landmark. The entire former D&H Canal system was designated a National Historic Landmark in 1968.
Roebling went on to engineer the Brooklyn Bridge, though he died in 1869 after he suffered injuries sustained while planning that landmark’s construction. His son Washington Roebling oversaw the bridge’s completion 14 years later.
Though nowhere near as grand and as celebrated as the Brooklyn Bridge, the Delaware Aqueduct is still a fascinating remnant of engineering history sympathetically rehabilitated to suit modern needs.