In the early 18th century, one of the main modes of transportation for goods between DC and Virginia was by boat and waterway. The continued development of the Chesapeake and Ohio Canal (C&O Canal), however, worried merchants at the Alexandria port, also on the Potomac River, about losing business to the rival Georgetown port. In order to avoid economic losses, engineers with the C&O Canal Company and the Alexandria Canal Company created a plan to build the Potomac Aqueduct Bridge, which would allow goods to cross the river and merchants to share business on both sides of the river.
The project began in 1833 and was headed by Major William Turnbull, who worked for the U.S. Topographical Engineers (later known as the U.S. Army Corps of Engineers). While Turnbull’s passion and hopes for the project showed in his designs, it was marred with logistical and construction problems throughout its entirety. Engineers and workers consistently fought against mud and water seeping into the channel they were digging. Additionally, funding problems plagued the project after the federal government ended its financial support.
Despite the troubles, the Aqueduct Bridge opened in 1843, ten years after construction began, and gained major traffic. The bridge was considered an engineering feat because the bridge’s supports and cofferdams reached new depths of 35 feet below the surface. After opening, the bridge expanded to include foot and carriage traffic on a second level. Additional expansion plans were initially explored, but the outbreak of the Civil War created a new purpose for the bridge. Throughout the war, the bridge was drained and used to carry military supplies across the Potomac, with soldiers stationed on the Virginia side.
After the war, the bridge opened again to the public, but the Alexandria Canal Company had leased the bridge to the Alexandria Railroad & Bridge Company, who began charging a toll to cross. This upset merchants and the public who had previously used the bridge without paying, and after many protests the bridge closed to all but foot traffic, which did not require the toll. This policy carried through until the Alexandria Canal Company sold the bridge in 1886.
While the bridge reopened under its new owners, many felt that the bridge simply couldn’t handle the amount of traffic that used it. Those feelings were solidified when, in 1920, plans to build Key Bridge began. When Key Bridge opened in 1924, the Potomac Aqueduct Bridge was still in use, but only for a short period of time. In 1933, the bulk of the bridge was demolished, with the rubble used to form seawalls at Anacostia Park. However, it took almost 30-years for the piers to be demolished. Today, only the abutments on either side of the Potomac River remain.
DC Inventory: January 23, 1973 (Joint Committee on Landmarks)