Since its construction in 1928, the Conowingo Dam, owned and operated by Exelon, on the Susquehanna River in Maryland has been trapping sediment and phosphorus pollution in the reservoir behind the structure. Today the reservoir is almost completely filled and, as a result, has lost much of its capacity to trap sediment and nutrients. In particular, during heavy rainstorms when the flow through the dam is high, these sediments are scoured from the reservoir and released into the river below. This results in a high amount of pollution flowing into the Bay in a short period, rather than gradually, which can overwhelm the Bay and fuel algal blooms that cause dead zones devoid of oxygen in the Bay.

CBF has a long legal history of involvement with the Conowingo Dam beginning in August 2013 when we first intervened in the Federal Energy Regulatory Commission’s (FERC) relicensing proceedings for the dam, provided comments on FERC’s Draft Environmental Impact Statement (DEIS), and Exelon’s Section 401 Water Quality Certification application with the State of Maryland. Eventually MDE issued its Certification on April 27, 2018, requiring Exelon to account for and reduce the amount of nitrogen and phosphorus discharged through the dam due to the inability of the dam to continue trapping these pollutants. In response to MDE’s certification, Exelon filed Judicial actions against MDE in May 2019 in both Maryland state court and federal court. CBF filed Motions to Intervene in both cases to ensure that the proper administrative process was followed and defend the State of Maryland’s authority to certify and condition discharges that would otherwise harm water quality.

However, prior to the cases being litigated, the State of Maryland filed a Settlement Agreement with FERC that would resolve all of Exelon’s judicial and administrative appeals. The settlement waived the requirement for a water quality certification and required Exelon to invest approximately $200 million adjusted for inflation over the 50-year license agreement term for environmental benefit projects, while not admitting any responsibility or liability for pollution scoured and discharged from the dam during high river flow events such as storms. On January 17, 2021, CBF filed comments on the Settlement Agreement with FERC urging the commission to reject the proposed settlement offer. However, on March 19, 2021, FERC issued an Order granting a new 50-year license to Exelon without imposing any conditions on the operation of the Dam that would mitigate its impact to downstream water quality.

CBF, along with our partners Waterkeepers Chesapeake, Lower Susquehanna Riverkeeper, and ShoreRivers, represented by Earthjustice, filed a request for a rehearing of FERC’s March 19th Order. After FERC denied our request, we filed a Petition for Review with the United States Court of Appeals for the D.C. Circuit on June 17, 2021, requesting the Court review FERC’s Order to issue the new license and a 2nd Petition for Review on September 13th based on FERC’s Order on our rehearing request.  Arguments were held on October 11, 2023.

In a win for the Chesapeake Bay, watermen, and residents downstream from the Dam, the D.C. Circuit Court of Appeals issued an opinion on December 20, 2022 vacating FERC’s 50-year license issued to Constellation Energy (formerly Exelon) to continue operating the Dam. The Court found that FERC violated the Clean Water Act when it issued the license without including the water quality certification that MDE had issued in 2018.

MDE is currently reconsidering the Water Quality Certification for the Dam and solicited public comments in August 2023. CBF is closely monitoring the license review process and providing input and comments where appropriate.

CBF was represented in this matter by the Vice President of Litigation Paul Smail.