Exelon Corporation, the owner of the Conowingo Dam on the lower Susquehanna River, has appealed Maryland’s issuance of a condition-laden water quality certification for the dam. The appeals, filed on May 25, 2018 in the District of Columbia Federal District Court, the Maryland Circuit Court in Baltimore, and the Maryland Department of the Environment, challenge Maryland’s water quality certification issued for Conowingo Dam pursuant to the Federal Clean Water Act on April 27, 2018. The outcome of this litigation could have a significant impact on funding for nutrient reduction efforts throughout the Chesapeake Bay watershed, particularly in Pennsylvania.
Among other things, Maryland’s certification requires that Exelon develop a sediment and nutrient management plan to eliminate six million pounds of nitrogen and 260,000 pounds of phosphorus that would ultimately otherwise pass through the dam into the Chesapeake Bay. Maryland would allow Exelon several options to meet the reduction requirement, such as dredging the sediments trapped behind the dam. The likely way Exelon would achieve this goal, however, would be through the payment of in-lieu annual fees of $17 per pound of nitrogen and $270 per pound of phosphorus, for a total annual expenditure of approximately $172 million. A significant portion of these funds may be available for the implementation of nutrient reduction projects in Pennsylvania.
Maryland’s water quality certification was issued in the context of Exelon’s application to the Federal Energy Regulatory Commission to renew its operating license for the Conowingo Dam. Located in Maryland just below its border with Pennsylvania, the dam has over the years trapped nutrient rich sediments, thereby limiting their release downstream to the Chesapeake Bay. There is no longer capacity for the dam to trap these sediments, thereby creating a greater risk to Chesapeake Bay water quality. Pennsylvania is by far the largest contributor of nutrients to the Susquehanna River, primarily from agriculture and stormwater discharges.