The Patowmack Canal, sometimes called the Potomac Canal, is a series of five inoperative canals located in Maryland and Virginia, United States, that was designed to bypass rapids in the Potomac River upstream of the present Washington, D.C., area. The most well known of them is the Great Falls skirting canal, whose remains are managed by the National Park Service as it is within Great Falls Park Virginia, an integral part of the George Washington Memorial Parkway.
The first section of the canal opened in 1795, and the canal ended operations in 1828.
Few ventures were dearer to George Washington than his plan to make the Potomac River navigable as far as the Ohio River Valley. In the uncertain period after the Revolutionary War, Washington believed that better transportation and trade would draw lands west of the Allegheny Mountains into the United States and “bind those people to us by a chain which never can be broken.”
“The way,” Washington wrote, “is easy and dictated by our clearest interest. It is to open a wide door, and make a smooth way for the produce of that Country to pass to our Markets.”
As a waterway west, the Potomac River could be that “door.” It was the shortest potential route between tidewater, with access to East Coast and trans-Atlantic trade, and the headwaters of the Ohio River, with access to the western frontier. But both political and physical obstacles had to be overcome.
Opening the Potomac required cooperation of Virginia and Maryland, both of which bordered the river. In 1784, Washington convinced the states’ assemblies to establish a company to improve the Potomac between its headwaters near Cumberland, Maryland, and tidewater at Georgetown. The Patowmack Company, organized May 17, 1785, drew directors and subscribers from both states. Then, Washington wrote in his diary, the office of president of the Patowmack Company “fell upon me.” He presided over the project until he became the nation’s chief executive (President of the United States).
Delegates from Virginia and Maryland, meeting at Washington’s home in 1785, drew up the Mount Vernon Compact, providing for free trade on the river. Virginia and Maryland legislators ratified the compact and then invited all 13 states to send delegates to a convention in Annapolis in 1786 “to consider how far a uniform system in their commercial regulations may be necessary to their common interest.” The Annapolis Convention led to a general meeting in Philadelphia the following May. Thus, George Washington’s lobbying for interstate cooperation on the Potomac helped prepare the way for the Constitutional Convention of 1787.