Allegheny River at Natrona Lock and Dam, PA
River level and flood forecast · Allegheny County
The river is 9.6 ft below flood stage (21 ft).
Forecast to rise to 11.9 ft Tue 2 AM, below the 21 ft flood stage.
Flow: 11,200 cubic feet per second (USGS).
The last 7 days and the forecast
NWS forecast issued Mon, Oct 12, 9:20 AM. Forecasts change as rain falls and as upstream water arrives.
Flood stages
| Major flood stage | 26 ft |
| Moderate flood stage | 24 ft |
| Flood stage | 21 ft |
| Action stage | 17.2 ft |
| Record crest (March 18, 1936) | 32.1 ft |
What floods at each level
From the National Weather Service, highest first.
- 29.4 ftPennsylvania Railroad main line and sidings affected at Tarentum PA, 3 miles downstream floods.
- 21.5 ftThe Natrona Water Company is affected.
- 21.3 ftWater begins to back up into the sewers at Braeburn Steel Co.
- 21 ftLock walls overtopped.
- 18 ftNavigation suspended, lock out of service.
Highest crests on record
- 32.1 ft — March 18, 1936
- 28.4 ft — December 30, 1942
- 27.6 ft — January 22, 1959
- 27.5 ft — June 23, 1972
- 26.4 ft — March 10, 1964
Recent crests: 18.52 ft (February 19, 2022) · 18.63 ft (February 9, 2019) · 17.84 ft (March 24, 2007) · 21.4 ft (March 16, 2007) · 20 ft (January 7, 2005)
Up and down the river, and nearby
- UpstreamAllegheny River at Freeport Lock and Dam, PA
- DownstreamAllegheny River at C.W. Bill Young Lock and Dam, PA
- Buffalo Creek (PA) at Iron Bridge, PA
- Kiskiminetas River at Vandergrift, PA
- Allegheny River at Clinton Lock and Dam, PA
- Crooked Creek at Crooked Creek Dam Tailwater, PA
- Little Pine Creek near Etna, PA
- Allegheny River at Sharpsburg Lock and Dam, PA
Not an official source. River levels, forecasts, flood stages and impacts are from the National Weather Service (NATP1); flow from the U.S. Geological Survey. Readings are provisional. In a flood, follow your local officials and the NWS at weather.gov.