About the River and the Dam

Conowingo Dam fact sheetConowingo Dam is located on the Susquehanna River about 10 miles upstream from where it flows into the Chesapeake Bay at Havre De Grace, Maryland. Owned and operated by Exelon Corporation, the dam has been trapping sediment from the Susquehanna River, blocking fish passage, and affecting the water quality of the Bay since it was built in 1928.

Conowingo’s federal license is now up for renewal, and this may be the only opportunity in the next 50 years to get meaningful pollution reductions at the dam. Learn more »

The Federal Licensing Process

Exelon Corporation owns and operates the dam. Exelon’s current license expired in 2014, and it is seeking a new 50-year license from the Federal Energy Regulatory Commission (FERC). Before FERC grants a new license, the State of Maryland must certify that the project will meet state water quality standards. This water quality certification is required under section 401 of the federal Clean Water Act.

On April 27, 2018, the Maryland Department of the Environment issued a Water Quality Certification for the proposed relicensing of the Conowingo Dam. Waterkeepers Chesapeake and Lower Susquehanna Riverkeeper believe that Maryland’s Water Quality Certification is incomplete because it is missing several key elements. Learn more »

Conowingo Dam and the Chesapeake Bay

Since its construction in 1928, Conowingo Dam has trapped polluted sediment from the Susquehanna River and its 27,000-square-mile drainage area. Scientists have concluded that the dam’s reservoir is now at capacity and studies estimate that there are nearly 200 million tons of sediment, nutrients and other pollutants trapped behind the dam. During major floods caused by large storms, powerful floodwaters can scoop out or “scour” the stored sediment behind the dam and send that downstream to the Chesapeake Bay in the form of pollution. Learn more »