West Branch Susquehanna River at Lewisburg, PA
River level and flood forecast · Northumberland County
The river is 15.5 ft below flood stage (18 ft).
Forecast to rise to 3.7 ft Wed 2 PM, below the 18 ft flood stage.
Flow: 3,510 cubic feet per second (USGS).
The last 7 days and the forecast
NWS forecast issued Mon, Oct 12, 2:51 PM. Forecasts change as rain falls and as upstream water arrives.
Flood stages
| Major flood stage | 28 ft |
| Moderate flood stage | 23 ft |
| Flood stage | 18 ft |
| Action stage | 14 ft |
| Record crest (June 24, 1972) | 34.23 ft |
What floods at each level
From the National Weather Service, highest first.
- 40 ftApproximate level of the FEMA 0.2% Annual Chance Flood level (500-year flood).
- 34.2 ftFlood of record from Hurricane Agnes in 1972.
- 32.5 ftApproximate level of the FEMA 1% Annual Chance Flood level (100-year flood).
- 32 ftFlood waters begin to reach the Market Street Bridge. The intersection of 4th and Catherine Streets is inundated. A significant portion of Lewisburg is inundated.
- 30 ftApproximate level of the FEMA 2% Annual Chance Flood level (50-year flood).
- 28 ftThe right, or west bank overflows and affects Lewisburg. Widespread inundation on the left bank affects several mobile home parks. Many residences and businesses on both banks are affected by flood waters.
- 25.5 ftApproximate level of the FEMA 10% Annual Chance Flood level (10-year flood).
- 25 ftLow lying areas on the right, or west bank are affected. The left bank continues to experience inundation.
- 23 ftThe mobile home park along Route 405 downstream of the bridge will flood.
- 21 ftThe left, or east bank experiences substantial overflow.
- 19 ftRoute 405 is affected downstream of the Lewisburg Bridge.
- 18 ftThe left, or east bank overflows. Low lying areas will flood.
Highest crests on record
- 34.23 ft — June 24, 1972
- 28.43 ft — May 29, 1946
- 27.62 ft — September 27, 1975
- 26.16 ft — March 11, 1964
- 26.05 ft — November 26, 1950
Recent crests: 19.35 ft (September 12, 2018) · 25.91 ft (September 8, 2011) · 20.13 ft (April 29, 2011) · 20.78 ft (March 12, 2011) · 20.9 ft (December 2, 2010)
Up and down the river, and nearby
- UpstreamWest Branch Susquehanna River at West Milton, PA
- Chillisquaque Creek near Potts Grove, PA
- Susquehanna River at Sunbury above Dam, PA
- Susquehanna River at Sunbury, PA
- West Branch Susquehanna River at Allenwood, PA
- Penns Creek at Penns Creek, PA
- Chillisquaque Creek at Washingtonville, PA
- Susquehanna River at Danville, PA
Not an official source. River levels, forecasts, flood stages and impacts are from the National Weather Service (LWBP1); flow from the U.S. Geological Survey. Readings are provisional. In a flood, follow your local officials and the NWS at weather.gov.