The outlook for more climate-related flooding in a southeastern Pennsylvania watershed has prompted a new call for measures to contain heavy rains, allow raging waters to pass downstream and help the public anticipate bigger and more frequent storms.
The Brandywine Flood Study, prepared by the nonprofit Brandywine Conservancy, the University of Delaware Water Resources Center and a local flood-control agency, says more land should be set aside for open space that could absorb rains before they become floods. The report also calls for more bridges, dams and culverts to be repaired, removed or enlarged to cope with increased water flows that would otherwise flood the area and urges the construction of more green infrastructure such as rain gardens to absorb heavy rains.
The recent study was prompted in part by the remnants of Hurricane Ida in September 2021. The storm triggered record flooding and water flows in the Brandywine Creek in Pennsylvania and Delaware, causing some $45 million in property damage and taking one life.
The study, a draft that will be finalized in April, was also driven by the Brandywine watershed’s long history of flooding and by the outlook for more and bigger storms fueled by the warming planet. Ida was just one—albeit the most severe—of 10 high-precipitation storms to hit the watershed between 2003 and 2021. It followed dozens of others in the 19th and 20th centuries.