St Marys River at Great Mills, MD
Is St Marys River at Great Mills, MD flooding right now?
St Marys River at Great Mills, MD measured 1.46 ft on 2026-09-11 01:15:00 UTC. That observation was 5.5 ft below its 7 ft flood stage. This is the latest available reading, not a guarantee of current conditions.
Gauge height
1.46 ft
Streamflow
7 cfs
Minor flooding here begins at 7 ft, with major flooding at 10 ft. The highest crest on record was 13.34 ft on Wed, Aug 20, 1969.
Streamflow outlook
Flood stages at this gauge
| Category | Stage | Current distance |
|---|---|---|
| Action | 5 ft | 3.5 ft below |
| Minor flood | 7 ft | 5.5 ft below |
| Moderate flood | 8 ft | 6.5 ft below |
| Major flood | 10 ft | 8.5 ft below |
Highest crests on record
| Stage | Date |
|---|---|
| 13.34 ft | 1969-08-20 |
| 12.98 ft | 2011-08-28 |
| 12.82 ft | 1999-09-16 |
| 12.08 ft | 1960-07-30 |
| 11.77 ft | 1955-08-13 |
Nearby gauges
| Gauge | Distance | County |
|---|---|---|
| Mcintosh Run near Leonardtown, MD | 9.3 mi | St. Mary's County |
| St Clements Creek near Clements, MD | 13.6 mi | St. Mary's County |
| St Leonard Creek near St Leonard, MD | 14.3 mi | Calvert County |
| Killpeck Creek at Huntersville, MD | 20.5 mi | St. Mary's County |
| Cat Point Creek near Montross, VA | 22.4 mi | Richmond County |
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Provisional data: Real-time readings are provisional and subject to revision by the USGS — sensors can be affected by ice, debris, or equipment malfunction. Do not rely on this site for decisions involving personal safety; follow official guidance from the National Weather Service and local authorities.