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Energy & Environment

Conowingo Dam license invalidated by appeals court

Conowingo Dam
U.S. Geological Survey staff collect water samples at the Conowingo Dam. USGS photo.

By John Domen

A federal appeals court vacated a 50-year operating license for Constellation Energy‘s Conowingo Dam, which sits on the Susquehanna River, the Chesapeake Bay’s largest source of fresh water.

The judges ruled that the Federal Energy Regulatory Commission violated the federal Clean Water Act in giving the permit, after the state of Maryland and Constellation agreed to scrap a water quality certification process it had originally issued.

That prompted a coalition of environmental groups to file a lawsuit.

“It means that the state of Maryland has to take a serious look at its responsibilities under the Clean Water Act and make sure that it puts conditions on the water quality certification that protect clean water while the dam continues to operate,” said Allison Prost, the vice president of environmental protection and restoration with the Chesapeake Bay Foundation. The CBF was one of the groups involved in the lawsuit.

“A private company benefits from that water source (the Susquehanna) and therefore have a responsibility to make sure that they are not increasing the pollution loads downstream, that they are meeting water quality standards,” said Prost. “We do think that the dam operators have a responsibility. We did not think that the settlement agreement that the state of Maryland entered into was protective of water quality.”

Prost said the new settlement would have waived the right to require water quality certification, and waived the right to require pollution limits from the dam in the future.

“In our opinion the dam operator was getting off with continuing pollution when everyone else is trying to do more to clean up the Susquehanna and the bay,” she said.

Several calls to Constellation and messages left through multiple social media channels went unanswered. The Maryland Attorney General’s Office, which represented the state in the litigation, said it would not comment.

The invalidation of the federal license for the dam sends the matter back to the Federal Energy Regulatory Commission for further proceedings.

For now, Conowingo Dam will be required to operate on an annual license, instead of one that runs for 50 years, until Maryland finishes another water quality certification process.

The water quality certificate issued in 2018 included conditions requiring Constellation to reduce the amount of nitrogen and phosphorous discharged through the dam, improve fish and eel passage upstream, along with other actions. Maryland agreed to scrap those requirements after Constellation pushed back on them, though other environmental groups are challenging some of those conditions too, saying those don’t go far enough. But with the new agreement in place, the Federal Energy Regulatory Commission issued an operating license good for 50 years.

Environmental groups then sued, saying the state wasn’t legally allowed to waive the original 2018 certification, under the terms of the Clean Water Act. The appeals court panel agreed, and vacated the 50-year license. Judge David Tatel wrote in the ruling that doing so “will allow completion of the administrative and judicial review that was interrupted by the settlement agreement. That review could result in either (1) the invalidation of Maryland’s 2018 certification, which would require Constellation to request a new certification, or (2) the validation of the 2018 certification, which would require FERC to issue a license incorporating the conditions contained in therein.”

Tatel concluded by saying that either one of those results would be in compliance with the federal Clean Water Act.

As part of Maryland Matters’ content sharing agreement with WTOP, we feature this article from John Domen. Click here for the WTOP News website.