Rivers in Maryland
Potomac River at Hancock
Below flood stage
3.24ftStage
Observed Tue, Sep 22, 5:15 AM EDT
- Flood stage
- 25.00 ft
- Forecast crest
- 7.10 ftWed, Sep 23, 2:00 PM EDT
- Record crest
- 47.60 ft1936
Flood stages and impacts
| Category | Stage |
|---|---|
| Major flood | 35.00 ft |
| Moderate flood | 33.00 ft |
| Minor flood | 25.00 ft |
| Action | 21.00 ft |
- 56.00 ftWater approaches the highest point on Main Street.
- 46.00 ftWater floods the railroad depot.
- 45.00 ftFloodwater isolates the town of Hancock.
- 40.00 ftWater floods 25 to 30 homes along the West Virginia side of the river just downstream from Hancock, and at least another 20 to 30 in Hancock itself.
- 35.00 ftWater inundates 20 to 30 homes and 5 or more businesses in the west end of Hancock.
- 33.00 ftWater floods low spots on East Main Street in Hancock.
- 31.00 ftWater begins to flood low spots of West Main Street in Hancock.
- 30.00 ftWater begins to inundate homes and business in Hancock. Water covers the road to the maintenance shop for the National Park Service near Hancock. The west end of the Potomac Airpark runway begins to flood.
- 28.00 ftWater begins to inundate some yards on the west end of Hancock. Water also begins to collect on the west end of the CSX Railyard on the West Virginia side.
- 25.00 ftWater may begin to inundate low points of the CSX Railroad tracks on the West Virginia side of the river due to backwater. Additionally, access to Potomac Airpark may be restricted due to backwater. Water reaches the top of the Hancock boat ramp and begins to spill over into the adjacent parking lot.
- 24.00 ftWater begins to overflow into low lying areas.
- 21.00 ftThe boat ramp at Four Locks is covered by water. Half the parking lot there is also covered.
- 18.50 ftWater enters the canal prism and blocks the towpath at MP 106.
- 7.50 ftThe river is at danger level for boaters as defined by the State of Maryland. At these levels, conditions are extremely hazardous.
- 3.50 ftThe river reaches caution level for boaters as defined by the State of Maryland. Fast moving water and changing currents can be expected.
Flood outlook
Chance of flooding, September to November
| Category | Chance |
|---|---|
| Minor flooding | 7% |
| Moderate flooding | Under 5% |
| Major flooding | Under 5% |
The three-month chances are the River Forecast Centers’ long-range flood outlook, issued August 28, 2026.
Crest history
55 crests on NOAA’s list since 1889.
| # | Date | Stage |
|---|---|---|
| 1 | March 18, 1936 | 47.60 ft |
| 2 | November 6, 1985 | 41.20 ft |
| 3 | June 1, 1889 | 40.00 ft |
| 4 | October 16, 1942 | 36.63 ft |
| 5 | January 20, 1996 | 36.26 ft |
| 6 | September 8, 1996 | 35.81 ft |
| 7 | April 27, 1937 | 35.70 ft |
| 8 | May 13, 1924 | 35.00 ft |
| 9 | May 1, 1889 | 34.00 ft |
| 10 | March 30, 1924 | 32.40 ft |
| 11 | August 19, 1955 | 32.40 ft |
| 12 | October 29, 1937 | 31.80 ft |
| 13 | June 23, 1972 | 30.79 ft |
| 14 | April 17, 1929 | 30.30 ft |
| 15 | October 10, 1976 | 28.56 ft |
| 16 | March 8, 1967 | 26.91 ft |
| 17 | June 19, 1949 | 26.86 ft |
| 18 | May 9, 1960 | 26.60 ft |
| 19 | June 4, 2018 | 26.38 ft |
| 20 | May 15, 2025 | 26.30 ft |
| 21 | March 21, 1963 | 26.24 ft |
| 22 | September 20, 2003 | 26.09 ft |
| 23 | February 27, 1979 | 25.96 ft |
| 24 | March 14, 2010 | 25.94 ft |
| 25 | February 15, 1984 | 25.64 ft |
Most recent crests
- May 15, 2025: 26.30 ft
- December 16, 2018: 23.57 ft
- June 4, 2018: 26.38 ft
- May 17, 2014: 21.33 ft
- May 19, 2011: 25.41 ft
- March 14, 2010: 25.94 ft
- May 5, 2009: 22.36 ft
- April 16, 2007: 21.36 ft
- March 29, 2005: 23.26 ft
- September 20, 2003: 26.09 ft
Nearby
Upstream, downstream and the gauges around this one.
What this means
Forecasts by the Middle Atlantic River Forecast Center. Forecasts are issued routinely year-round. Stage may be affected by ice.
Sources
Stage, flood stages, impacts and crest history from NOAA’s National Water Prediction Service. Streamflow and the daily record from the U.S. Geological Survey.