The Conowingo Dam poses significant water quality risks that could potentially lead to the imposition of more stringent regulatory requirements on Pennsylvania farmers and municipalities located in the Chesapeake Bay watershed. The Conowingo Dam, one of three dams on the lower Susquehanna River and located just over the Pennsylvania border in Maryland, has, since its construction in 1928, captured nutrient rich sediments in its reservoir, thereby reducing the release of this material into the Chesapeake Bay. Nutrients, such as nitrogen and phosphorus, and sediments are the primary causes of decreased water quality in the Bay.
Unfortunately, the reservoir behind the dam is essentially full, which means that its ability to hold back additional contaminants from the Chesapeake Bay is essentially nonexistent. Particularly during large storms and severe floods, sediment and attached nutrients can “scour” into the Susquehanna, moving over the dam and into the Chesapeake Bay. Should this continue over time, it could have a significant impact on Chesapeake Bay water quality.
Why should Pennsylvania farmers and municipalities be concerned? Pennsylvania is currently on a “nutrient diet” imposed by the U.S. Environmental Protection Agency. Farmers are facing increased scrutiny and requirements to implement best management practices to reduce the release of nutrients to local streams. Municipalities are also being required to reduce stormwater flows. If releases of nutrient rich sediments from behind Conowingo Dam significantly reduce Chesapeake Bay water quality, it is very possible that federal and state regulatory agencies would impose more stringent requirements on Pennsylvania municipalities and the agricultural community to compensate for the increased releases from Conowingo Dam.
Exelon Corporation, the owner of Conowingo Dam, has applied to the Federal Energy Regulatory Commission (“FERC”) to relicense the dam. It is likely that any relicensure will include requirements to address these environmental issues. A number of parties have intervened in the FERC proceedings, but apparently none directly representing Pennsylvania agriculture and municipal interests. Attorneys in Stock and Leader’s Environment and Energy Group are monitoring the FERC proceedings and other issues related to the Conowingo Dam that could impact Pennsylvania municipalities and farmers.