TidalMapPatapsco River at Hollofield, MD Water Level Today
NWS river forecast
| When | Stage | Flow |
|---|
Forecast from the NOAA National Water Prediction Service. Issued a few times a day and only while a forecast is active. Not for navigation.
Last 30 days
About this gauge
USGS gauge 01589000 sits on the Patapsco River and reads everything draining 285 square miles of the Gunpowder-Patapsco basin. Its datum sits 187 feet above sea level NAVD88. Daily flow has been on record here since 1944, 69 years of it.
Where this gauge sits in the drainage
One gauged site sits upstream of here. The closest is North Branch Patapsco River at Cedarhurst, MD, reading 57 square miles. This gauge adds the 228 square miles that drain in between. Downstream the next reading comes from Patapsco River near Catonsville, MD at 301 square miles, so what passes this gauge is about 95% of the water measured there. Water passing here goes on to Patapsco River near Elkridge, MD.
Normal flows here
The Patapsco River runs a median of 110 cfs at this gauge across 69 years of record. March is the fullest month at a median 210 cfs, and September the leanest at 56 cfs. The highest daily mean on record is 30,000 cfs in 1972, and the lowest is 5.9 cfs in 2002.
| Month | Median flow | Share of annual median |
|---|---|---|
| Jan | 132 cfs | 120% |
| Feb | 151 cfs | 137% |
| Mar | 210 cfs | 191% |
| Apr | 194 cfs | 176% |
| May | 169 cfs | 154% |
| Jun | 114 cfs | 104% |
| Jul | 76 cfs | 69% |
| Aug | 65 cfs | 59% |
| Sep | 56 cfs | 51% |
| Oct | 60 cfs | 55% |
| Nov | 83 cfs | 75% |
| Dec | 106 cfs | 96% |
Medians from the USGS daily-statistics record, 1944 to 2026. A month at 100% is running at its own long-term median.
Flood stages and record crests
The Patapsco River reaches flood stage at this gauge at 11 feet. NWS starts watching it at 9 feet. The highest crest on record is 31.3 feet, in June 1972.
| Category | Gage height |
|---|---|
| Action | 9 ft |
| Minor flooding | 11 ft |
| Moderate flooding | 19 ft |
| Major flooding | 25 ft |
| When | Crest |
|---|---|
| June 1972 | 31.3 ft |
| September 1975 | 22.8 ft |
| August 1933 | 19.5 ft |
| July 1956 | 15.9 ft |
| July 2016 | 14.2 ft |
Flood categories and crest history from the NOAA National Water Prediction Service, gauge PRHM2. Stages are gage height, not depth. Not for navigation.
Nearby river gauges
- Dead Run Tributary near Woodlawn, MD
- Tributary to Dead Run Tributary at Woodlawn, MD
- Dead Run near Catonsville, MD
- Dead Run Tributary at Woodlawn, MD
- Scotts Level Branch at Rockdale, MD
- Dead Run at Woodlawn, MD
- Patapsco River near Catonsville, MD
- Dead Run at Franklintown, MD
- Red Run near Owings Mills, MD
- Patapsco River near Elkridge, MD
- East Branch Herbert Run at Arbutus, MD
- Little Patuxent River at Guilford, MD
Live streamflow and gage height: USGS gauge 01589000. Percentile context computed against the gauge's period of record. Not for navigation.
Open Patapsco River at Hollofield, MD on the live chart →
River pins, dam-release overlays and wadability lines live in the app, start a free TidalMap trial.