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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 Field Guide to Rivers of North America
Physiographic provinces:

Appalachian Plateau (AP), Valley and Ridge (VR), Piedmont Plateau (PP), Blue Ridge (BL), Coastal Plain (CP)

Major fishes:

smallmouth bass, channel catfish, spottail shiner, spotfin shiner, bluntnose minnow, redhorse sucker, redbreast sunfish, bluegill, tessellated darter

Major other aquatic vertebrates:

beaver, muskrat, common snapping turtle, eastern painted turtle, great blue heron, bald eagle, osprey, Canada goose

Major benthic insects:

mayflies (Anthopotamus, Caenis, Ephoron, Serratella, Stenonema, Tricorythodes), caddisflies (Hydropsyche, Cheumatopsyche, Hydroptila, Potamyia, Macrostemum), true flies (Thienemannimyia, Tanytarsus, Cricotopus, Polypedilum, Cryptochironomus, Synorthocladius)

Nonnative species:

smallmouth bass, channel catfish, common carp, northern pike, muskellunge, Asiatic clam, hydrilla, Eurasian watermilfoil

Special features:

second-largest tributary to Chesapeake Bay, 174 km tidal/estuarine section

Fragmentation:

High, but only 3 impoundments >4 km2; >60 blockages in the Anacostia basin being removed or altered for fish passage.

Potomac River near Harper’s Ferry, West Virginia.

(photo by A. C. Benke)

Copyright © 2010, Elsevier Inc. All rights reserved.

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Full text Article Potomac River
Field Guide to Rivers of North America

Relief: 1481 m Basin area: 37,995 km 2 Mean discharge: 320 m 3 /s Mean annual precipitation: 99 cm Mean air temperature: 12.3°C...

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