Chester County Creek Will Hit Major Flood Stage, Says National Weather Service

CHESTER COUNTY, PA — The National Weather Service project Wednesday afternoon that Brandywine Creek in Chester County will hit Major Flood Stage Thursday morning as heavy rainfall sinks into already wet ground and the creek rises overnight.

Residents and commuters along the Brandywine are advised to take action now to avoid property damage and loss of life, Chester County Emergency Services said Wednesday afternoon.

The Brandywine Creek at U.S. 1 is projected to crest at 14.7 feet some time Thursday morning after Tropical Depression Ida's deluge of rain on Chester County and the Mid-Atlantic region.

The National Weather Service reported the Creek at 2.34 feet just before 3 p.m. Wednesday.

Major Flood Stage is marked at 13 feet and Flood Stage is 9 feet, and 11 feet is considered Moderate Flood Stage, according to the NWS.

The 13-feet Stage is the point when evacuations may begin and Rt. 100 and U.S. 1 may be closed, according to the NWS site.

Chester County Emergency Service on Wednesday reminded anyone driving that 12 inches of rushing water can carry away most cars. Drivers are told to heed barriers blocking traffic from flooded areas and not to drive through still or moving water.

All of Chester County is under a Flash Flood Watch Wednesday afternoon after it was also included among 11 southcentral PA counties that were under a Tornado Watch until 1 p.m. on Wednesday. The fallout of Tropical Depression Ida has not passed with the Tornado Watch lifting.

The National Weather Service has issued the Flash Flood Watch for Chester County and a swath of eastern Pennsylvania as heavy rainfalls in the area Wednesday afternoon. Between 3 and 6 inches of rain is expected to fall before the storm system passes, but the NWS said there could be more in some places. The rain was forecast to fall heavily in a short time, said the NWS.

Historic crests of Brandywine Creek — over the past century — occurred in 1999 when it hit 17.15 feet; 1972, when it hit 16.56 feet; 2014 when it hit 16.05 feet; 2011 when it hit 15.23 feet, and 1920 when it hit 15 feet, according to the NWS.

Recent crests over 9 feet happened in August 2020 when Brandywine Creek hit 10.93 feet, and in January 2020 when it reached 9.6 feet. In June 2019 it reached 9.27 feet and in November 2018 it hit 9.93 feet.

More information can be found here.

The Flash Flood Watch extends into Thursday for portions of Pennsylvania and New Jersey, including these areas: Pennsylvania counties; Berks., Carbon, Delaware, Eastern Chester, Eastern Montgomery, Lehigh, Lower Bucks, Monroe, Northampton, Philadelphia, Upper Bucks, Western Chester, and Western Montgomery.

What's left of Ida will move off the Northeast Coast on Thursday morning, leaving the floods to rise on the already soggy Mid-Atlantic region. Friday is forecast to be sunny with a high temperature of 74 degrees in Chester County.

What's the difference between a Watch and a Warning? Read about it here.

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