Court of Appeals Vacates Maryland’s Conowingo Dam License, Offering New Chance for Chesapeake Bay Protections

Today, the U.S. Court of Appeals in Washington, D.C., vacated the license issued by the Federal Energy Regulatory Commission (FERC) for Conowingo Dam. It ruled that FERC had no authority to issue a license based on Maryland’s after-the-fact withdrawal and “waiver” of its Water Quality Certification granted for the Dam in 2018. The state attempted to waive the certification in a settlement agreement with the Dam’s operator, Constellation Energy. 

By vacating the 50-year license FERC issued in 2021, the Court of Appeals is in effect re-starting challenges by the utility and others to the water quality certification that Maryland issued before entering the settlement agreement with the Dam’s operator.  

Chesapeake Bay Foundation (CBF) has consistently challenged Maryland’s Conowingo Dam settlement with Constellation, which split from the Exelon in 2022, because it failed to protect water quality in the Susquehanna River, the Bay’s primary tributary. Among its failures: 

  • It forfeited Maryland’s right to modify the dam’s pollution permit, preventing the state from requiring Exelon to reduce pollution coming from the dam for the next 50 years. 
  • It didn’t expressly require Exelon to add the pollution reduction measures the company said it would fund as part of the settlement. 
  • It did not focus settlement funds to Pennsylvania, where pollution projects are most urgently needed to address Bay pollution being exacerbated by the dam’s presence on the Susquehanna River. 

Over time, Conowingo Dam went from a pollution preventer that trapped sediment and pollutants in the reservoir behind the dam to a pollution source after the reservoir filled up. Strong storms that produce significant rainfall cause scour events during which large amounts of water flowing through the dam wash the sediment, debris, and pollutants trapped behind the dam into the lower reaches of the Susquehanna River and the Chesapeake Bay. This process alters the form and timing of pollutants that enter the Bay by causing large amounts of pollutants to flow through the dam all at one time, overwhelming natural systems. The pollutants then contribute to algal blooms that cause dead zones devoid of oxygen where marine life can’t survive. 

CBF attorneys Paul Smail and Brittany Wright worked on the case in the Court of Appeals along with James Pew of Earthjustice, who represented Waterkeepers Chesapeake. 

In response to the ruling, CBF’s Vice President of Environmental Protection and Restoration Alison Prost issued the following statement: 

“The court’s decision today is a cause for celebration among all who fight for and appreciate clean water. Maryland’s sweetheart deal with Constellation let the utility off the hook for what would have been decades of pollution related to the dam’s operations. Maryland leaders now have the opportunity to directly address the negative downstream impacts of the dam through a new license complete with a state water quality certification. We urge the state to use this opportunity to force Constellation to invest in upstream environmental projects that will offset the harm caused by the dam’s presence and protect the Chesapeake Bay for generations to come.”  

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A.J. Metcalf

Former Maryland Media & Communications Coordinator, CBF

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