Beginning August 12th, daily river forecasts will be issued for the Potomac River at Edwards Ferry, affecting adjacent portions of Loudoun County, VA and Montgomery County, MD. The Edwards Ferry forecasts will be in addition to similar services already provided upstream at Point of Rocks and downstream at Little Falls. However, flooding occurs more frequently near Edwards Ferry than at either of the other two locations, making a separate forecast location important for public safety, and movement of assets away from the river. Point of Rocks and Little Falls each reach their flood stages about once per year, on average. Since the Edwards Ferry gauge was installed in August 2011, it has recorded levels above flood stage 7 times.
Forecast guidance will be provided daily by the Middle Atlantic River Forecast Center, and forecasts will be updated more frequently when flooding threatens.
Flood stage at Edwards Ferry has been set at 15 feet. At this level, areas near Whites Ferry and Edwards Ferry begin to flood, and recreational interests along the C&O Canal towpath in that area should move away from the river. When the river is forecast to exceed 15 feet, a flood warning will be issued for a portion of Montgomery and Loudoun counties – although it is important to note that no impacts are observed in Loudoun County until the river reaches approximately 20 feet.
With the new forecast location at Edwards Ferry, the NWS Baltimore/Washington Forecast Office will provide daily routine river forecast and warning services at 32 distinct locations in the District of Columbia, Maryland, Virginia, and West Virginia, with high water forecasts available at another four locations.
For more information about this new service, contact:
Senior Service Hydrologist