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Definition: Potomac from Philip's Encyclopedia

River in E USA. It rises in West Virginia at the confluence of the North and South Branch rivers, and flows E and SE to Chesapeake Bay on the Atlantic coast, forming the boundaries of Maryland-West Virginia and Maryland-Virginia. Length: 462km (287mi).

Summary Article: Potomac River
from The Civil War Naval Encyclopedia

Strategically important river, some of which separates Maryland from the District of Columbia and Virginia. The Potomac River, one of four tidal rivers in the region, is 383 miles long and flows generally south and east until it empties into the Chesapeake Bay. The Chesapeake Bay's four major tidal rivers, from north to south, are the Potomac, Rappahannock, York, and James rivers. All of the lower Potomac lies within the state of Maryland. A small tidal portion, however, runs through the District of Columbia. The Potomac has two sources, which separate it into the North and South branches. Together, the river drains 14,768 square miles of area. The source of the North Branch is located at the junction of modern-day Tucker, Grant, and Preston counties in West Virginia. The South Branch's source is in northern Highland County, Virginia. The two branches converge in Hampshire County, West Virginia. The Potomac is tidal as far west as Washington, D.C., although the tidal range at that point is quite small.

Beginning in the early 18th century, white settlers—chiefly English—settled in the Potomac River Valley, generally from east to west. The watershed provided fertile land good for growing numerous crops and afforded inhabitants a ready supply of potable water. The river had great symbolic and strategic significance before and during the Civil War. The Lee family still had a sizable estate along its banks in 1861, and President George Washington's beloved Mount Vernon was also located along the Potomac. As a young surveyor, Washington himself had surveyed much of the Potomac River, from the Chesapeake west toward its two sources. The river's proximity to Washington, D.C., and Maryland, the dividing point between North and South, also gave the river special significance. Indeed, from the earliest days of the war, Union officials remained concerned about a Confederate attack on Washington, D.C., via the Potomac. During the early part of the 19th century, a series of canals was constructed to link inland waterways through the Potomac and into the Chesapeake Bay. The Chesapeake and Ohio Canal, completed in 1850, allowed shippers to go around the Great Falls, the fall line of the Potomac located about 15 miles upstream from Washington, D.C.

The Potomac was home to the Washington Navy Yard, located on the eastern branch in southeastern Washington, D.C. The yard served as the home base for the Potomac Flotilla during the Civil War and became a major repair facility for Union vessels. It also served the U.S. Navy as the epicenter of its Ordnance Department, where new guns and armor for ironclad ships were tested. In 1861 the Potomac Flotilla, whose primary goal was to defend Washington, D.C., was created as a “flying flotilla” that could also operate in the nearby Chesapeake Bay and tidal rivers, especially the Rappahannock. The flotilla was also designed to aid in the transport of supplies and troops to Washington, D.C., and northern Virginia. Several Union riverborne assaults, designed to cripple or destroy Confederate artillery batteries downriver, were launched from the area.

See also

James River; Potomac Flotilla; Riverine Warfare; Washington Navy Yard

  • Smith, J. Fawrence. The Potomac Naturalist: The National History of the Headwaters of the Potomac River. McClain Printing Parson, WV, 1968.
  • Tucker, Spencer C. Blue & Gray Navies: The Civil War Afloat. Naval Institute Press Annapolis, MD, 2006.
  • Pierpaoli, Paul G. Jr.
    Copyright 2011 by ABC-CLIO, LLC

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