Dignitaries launch a bi-state flood study at the Brandywine Museum of Art this past August in Chadds Ford, Delaware County. (JEN SAMUEL – FOR THE DAILY LOCAL NEWS)
COATESVILLE — For the city, residents remember vividly the devastating floodwaters brought by Tropical Storm Ida on the eve of September in 2021.
In America between 1980 to this past August, natural disasters have cost approximately $2.6 trillion in damages, according to the National Oceanic and Atmospheric Administration. Hurricane Ida caused an estimated $75 billion in damages and 96 deaths.
This past summer, Brandywine Conservancy announced a new partnership with the Chester County Water Resources Authority and the University of Delaware Water Resources Center to conduct a flood study to better understand where and why flooding occurs while identifying best practices to safeguard locals who live here from the severe flooding disasters in the future.
“As Hurricane Ida, and many prior floods have taught us, there is an urgent need for the Brandywine Flood Study so that we can identify ways to mitigate the impact of severe flooding events along the Brandywine Creek in both Pennsylvania and Delaware,” said Grant DeCosta, director of community services for the Brandywine Conservancy in in Chadds Ford, Delaware County.
The conservancy’s headquarters span 15 acres in both Delaware and Chester counties, along the Brandywine Creek. The location is also home to the Brandywine Museum of Art, which was severely flooded during Ida, although no rare paintings were lost during the historic event.
“Once the flood study is completed, the Brandywine Conservancy and its partners are committed to working with impacted communities, elected officials, key funders and government agencies to implement the study’s recommendations so that the watershed and its residents in both states are better prepared, protected and equipped to rebound from future severe flooding events,” DeCosta said.
Encompassing the mainstem of the Brandywine Creek and key tributaries in Chester and Delaware Counties in Pennsylvania and traveling downstream to impacted areas over the Delaware state line, the flood study aims to identify options for reducing flood impacts to improve public safety and lessen property damage, according to officials who delivered remarks during a press conference at the Brandywine Museum of Art in late August. The study will be funded, in part, through grants from Chester County Government and Delaware County Council.
‘Ground zero’
In July, the Federal Emergency Management Agency (FEMA) awarded Coatesville $621,360 in Flood Mitigation Assistance grant money to design and engineer long-term resilience solutions to reduce the potential for flooding within the municipality; the only city in Chester County.
“The grant will be utilized to address inefficiencies in our stormwater management network,” said City Manager James Logan, “which includes outdated pipes, inability to manage high volumes of water, and water flow challenges caused by the Brandywine River.”
Coatesville is built in a valley, and when the remnants of Hurricane Ida hit the city as a tropical storm, the overpowering rainfall swiftly toppled not only the nearby streams uphill, bringing floodwaters down to Olive Street along Fifth Avenue and elsewhere.
At Fifth and Sixth avenues and Olive Street, the floodwaters reached as high as stop octagons and street signs — up to 10 feet, as previously reported.
Linda Lavender-Norris, Coatesville City Council president, described the area as “ground zero.”
The infrastructure has yet to be replaced. Pennsylvania will receive $1.6 billion for bridge improvements, including for off-system bridges, from the $1.2 trillion Infrastructure Investment and Jobs Act, as previously reported. Additional money earmarked for Pennsylvania for infrastructure investments includes$11.3 billion for the federal highway program; $2.8 billion for public transportation; $1.4 billion for water infrastructure.
Located 39 miles west of Philadelphia and founded in 1915, Coatesville is home to 13,300 residents. When the dust settled after Ida two years ago, 130 homeowners and renters were left without a place to live.
After Ida, Cedarville Engineering Group recently evaluated the city’s stormwater mitigation system and infrastructure and determined Gibbons Run Culvert, which runs under Ash Park and west to the Brandywine, as a significant choke point, according to city officials. The culvert was overwhelmed by runoff and unable to transport enough stormwater from the area to reduce or prevent flooding.
“With this grant, we will be looking at developing a solution which will help build resiliency into the city’s infrastructure to help with similar events in the future,” said Kyle Turner of Cedarville.
While the existing infrastructure performed as expected, it could not accommodate the sheer volume of water and rise of the Brandywine, he said.
Chester County Commissioners approved a Declaration of Disaster Emergency during Ida and the county’s 911 Communication Center processed more than 4,000 calls, resulting in more than 300 storm-related rescues in a 10-hour time frame during Tropical Storm Ida. In Downingtown, there was one death because of the storm’s flooding.
Pennsylvania, home to more than 25,400 state-owned bridges, features 83,184 miles of streams and rivers, more than 4,000 lakes, reservoirs, and ponds, and 120 miles of coastal waters, as previously reported.
Only one state in America has more water than Pennsylvania: Alaska.
United partners
Led by the Brandywine Conservancy, Chester County and University of Delaware joint-study will evaluate the Brandywine Creek’s flow regimes during intense storm events, along with the scale and potential impact of subsequent flooding. Stroud Water Research Center, West Chester University and other technical experts as key partners will also take part.
“On behalf of Chester County, the Water Resources Authority is proud to be a partner in this watershed-based approach to identify a range of solutions that address flood impacts in our communities,” said Seung Ah Byun, executive director of the Chester County Water Resources Authority, on August 22.
“We also view this as a way to build resiliency and mitigate the potential effects from future storm events that may be larger and more intense due to our changing climate,” she said. “Approaching this from a more regional scale is important, because what our upstream communities do affects our neighbors downstream.”
Following the data gathering and field study phase, the partners will begin site assessment for improvements to the flood study area to mitigate future flooding. The recommended solutions will be evaluated for various factors, including impact and cost, in order to facilitate strategic implementation throughout the study area.
During Ida, the Brandywine Creek at Chadds Ford crested at over 21 feet — nearly four feet higher than the previous highest recording, as previously reported.
“We are thrilled to support the Brandywine Flood Study, led by the Brandywine Conservancy in partnership with the Chester County Water Resources Authority and the University of Delaware Water Resources Center,” said Monica Taylor of the Delaware County Council. “This coordinated effort will be key to helping us better protect our communities from future severe floods and will help us more fully understand and respond to all of the contributing factors that lead to extreme flooding along the Brandywine Creek.”
The Brandywine Conservancy expects that the flood study will be completed by June 2024.
One of the first tasks of the flood study will involve refining the study area to determine all the streams and tributaries with flow regimes that contribute to major flood events, according to
Nicole Kindbeiter, director of marketing and communications at the Brandywine Conservancy.
“The study partners will then evaluate the designated area’s storm event and climate data, population, land use, water quality, natural areas and cultural resources. Historical and present flooding data will also be evaluated, and then the partners will develop hydrologic and hydraulic models of the Brandywine Creek using the U.S. Army Corps of Engineers’ Hydrologic Engineer Center’s River Analysis System,” Kindbeiter said.
Then, “using these models, the partners will identify problems associated with the geography and hydrology of the flood study area. This process will also include public workshops and field reconnaissance of the defined study area,” she said.
“In 2021, Hurricane Ida sideswiped our area and caused the biggest flood in 200 years along the historic Brandywine Creek,” said Gerald Kauffman Jr., director of the University of Delaware Water Resources Center.
“We look forward to working with our upstream partners in this bi-state and intergovernmental Brandywine Flood Study to identify the root causes of the flooding, as well as recommend and hopefully implement real flood solutions for the people who live and work in the watershed in Delaware and Pennsylvania.”
