For decades, the land on the western bank of the Potomac River that is currently home to the Pentagon, Ronald Reagan National Airport, Roache’s Run Bird Sanctuary, and part of the George Washington Memorial Parkway was disputed territory. Did it belong to Virginia? The District? No one seemed quite sure.
The root of the problems can be traced back to conflicting charters and land grants in colonial times but the issues really started to mount in 1846. As students of D.C. history will remember, that was the year that the chunk of land that Virginia had ceded to the Federal government for the creation of the District of Columbia was retroceded back to Virginia.
Retrocession effectively set the Virginia boundary back to where it had been in 1791, when George Washington selected the site for the new Federal city that became Washington, D.C. Back then, the boundary between Maryland and Virginia had been disputed on and off for decades but a widely accepted view was that the line was the “high water” mark on the Virginia side of the river. In other words, Maryland (and, later, D.C) owned the river and islands, while Virginia owned everything that was connected to its mainland. Seems pretty simple, right? Not in the slightest.
Given the shifting nature of river banks, particularly tidal ones like the Potomac, and the existence of half-water/half-land marshy areas, the “high water” line was never much of a line at all. And when you add in man-made changes brought on by dredging, filling, and development, the landscape changed significantly over time. Areas that had been underwater in 1791 were dry land by the 1920s, which created some controversy.
Much of the dispute centered around Alexander’s Island, which was located where the Pentagon Connector parking lot now sits. Named for the Alexander family, who had a plantation on the site in the 18th century, Alexander’s Island earned its islandhood by virtue of some quite old maps, such as Andrew Ellicott’s 1793 map of the “Territory of Columbia.” That map showed a narrow strip of marshland called Roache’s Run separating approximately 500 acres from the mainland of Virginia. Other maps showed Roache’s Run as a body of water.
But over time, whatever separated Alexander’s island from Virginia’s mainland all but dried up. As the Evening Star reported in 1926, “In the course of years, the narrow channel became clogged. Gradually, the engineers believe, it underwent a process of evolution from open water into marsh and then into dry land inseparable from the Virginia shore.”