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Washington River Monitoring and Recreation Site
Little Falls is the end of a 10-mile stretch of rapids, falls, and swift water where the Potomac begins the transition from a free-flowing stream to a tidal estuary. At Little Falls (10 miles downstream from Great Falls), the tidal influence is actually felt. Little Falls is also the river's "head of navigation," meaning that ships cannot navigate the river any farther upstream.
The location played a key role in the choice of a site for the Nation's Capital. In 1790, Congress enacted a law directing George Washington to select a site for the seat of government for the United States to be somewhere on the Potomac between the Anacostia River and Conococheague Creek (70 miles upstream at the town of Williamsport, Md.). The law was called "The Residence Bill," and it included provisions for assuming northern states' debts from the Revolution in return for supporting the Potomac River site. Thomas Jefferson was involved in negotiating the compromise that resolved several important issues in the early days of the republic. George Washington made the logical choice: locating the city just below Little Falls made it accessible to river and ocean commerce, but at the same time it was far enough upstream to present problems for any foreign invader. (Of course, navigating the river was not a problem for the British, who burned the White House during the War of 1812, only two decades later).
Little Falls was the site of the Little Falls Skirting Canal, one of the canals built by Washington's Patowmack Company prior to the development of the C&O Canal.
Current stream conditions are shown in the graph below:
The National Oceanic and Atmospheric Administration (NOAA) has an on-line river forecast service for Little Falls available at this link. The forecast summary is shown below.
Flood Levels and Impacts
17 MOST OF THE C&O CANAL TOWPATH DOWNSTREAM OF EDWARDS FERRY IS FLOODED. TCHIFFELY MILL ROAD IS FLOODED DUE TO BACKWATER EFFECTS. WATER COVERS THE PARKING LOT AT THE ABNER CLOUD HOUSE IN THE DISTRICT OF COLUMBIA.
15 MOST OF THE C&O CANAL TOWPATH FROM EDWARDS FERRY DOWNSTREAM IS FLOODED. WATER COVERS THE LOCK AT EDWARDS FERRY. THE ACCESS ROAD TO VIOLETTES LOCK IS FLOODED. WATER IS FLOWING DOWN THE SIDEWALK NEAR THE GEORGETOWN VISITORS CENTER. THE FLETCHERS BOATHOUSE IS FLOODED.
14 SIGNIFICANT PORTIONS OF THE C&O CANAL TOWPATH ARE FLOODED. THE BLOCKHOUSE POINT PARK IS FLOODED.
13 SIGNIFICANT PORTIONS OF THE C&O TOWPATH ARE FLOODED.
12 THE C&O CANAL OVERFLOWS AT THE GREAT FALLS TAVERN. WATER COVERS THE TOWPATH IN MANY AREAS.
11.5 WATER COVERS THE TOWPATH BETWEEN THE WASHINGTON AQUEDUCT DAM AND SWAINS LOCK...MILEPOSTS 15 AND 16.
11 WATER COVERS THE TOWPATH BETWEEN SWAINS LOCK AND PENNYFIELD LOCK...MILEPOSTS 17 TO 19. THE BASEMENTS OF THE EDWARDS FERRY LOCKHOUSE AND RILEYS LOCKHOUSE ARE FLOODED.
10 WATER BEGINS TO OVERFLOW THE BANKS INTO LOW LYING AREAS ON THE MARYLAND SIDE OF THE RIVER NEAR LITTLE FALLS. UPSTREAM...THE PARKING LOT AT EDWARDS FERRY IS COMPLETELY COVERED BY WATER. THE PARKING LOT AT SENECA IS PARTIALLY COVERED BY WATER.
8.5 WATER REACHES THE BOAT RAMP AND LOWER PARKING AREA AT EDWARDS FERRY.
7 WATER REACHES THE WHITES FERRY AREA IN MONTGOMERY COUNTY MARYLAND. FERRY SERVICE MAY BE SUSPENDED.
5.5 WATER BEGINS TO AFFECT PORTIONS OF THE BILLY GOAT TRAIL BETWEEN GREAT FALLS AND CARDEROCK. THESE TRAILS MAY BE CLOSED.
4.5 THE RIVER REACHES DANGER LEVEL FOR BOATERS...AS DEFINED BY THE STATE OF MARYLAND. CONDITIONS FOR BOATING WILL BE EXTREMELY HAZARDOUS.
3.5 THE RIVER REACHES CAUTION LEVEL FOR BOATERS...AS DEFINED BY THE STATE OF MARYLAND. FAST MOVING WATER AND CHANGING CURRENTS WILL BE EXPERIENCED.
For detailed USGS real-time data on this site, select this link.
Nearby Potomac River Stream Monitors
To view a map of Potomac River Monitors, select this link.