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Heart of Controversy: How Conowingo Dam and Exelon’s Power Play are Impacting the Chesapeake Bay

Apr 19, 2016 02:11PM ● By Cate Reynolds
Conowingo Dam has reached the tipping point between trapping Susquehanna River’s upstream sediment/pollution and discharging it downstream into the Chesapeake Bay; so who will pay for the much-needed massive clean-up?

By Barbara Pash // Photography courtesy Chesapeake Bay Program

On a brilliant Sunday in late fall, down a winding road and around a bend, the Conowingo Dam comes into view. Massive and impressive, man-made and awe-inspiring, it could pass as one of the wonders of the world.

The dam spans the Susquehanna River, the main tributary of the Chesapeake Bay. In a shore-side visitors’ area, an elevated walkway allows a closer look at the dam, water tumbling through a few open gates.

On a pebbly beach below, a dozen fishermen cast their lines into the water. Downstream, several dozen bird-watchers gather. Binoculars in hand and cameras on tripods at the ready, they scan the sky for the eagles that also fish the river.

As peaceful as the scene appears, though, the Conowingo Dam is at the heart of a controversy. It concerns the estimated 200 million tons of sediment that has built up behind the dam, its spill-over during storms, and the effect on Bay habitats. It also concerns who is responsible and what should be done—a Pandora’s Box of conflicting opinions.

The controversy isn’t new. It has been building for well over a decade. But it appears to be coming to a head—and a possible resolution—within the next few years.

“Some groups blame all the problems of Bay pollution on the dam during storm events,” says Beth McGee, of the Chesapeake Bay Foundation, an Annapolis-headquartered nonprofit.

While not unsympathetic to the sediment situation, McGee, a senior water quality scientist, continues, “Our position is that collectively, the efforts that upstream states and Maryland need to make to reduce pollution are far more important than that one issue.”

The Conowingo Dam opened in 1928. It is located in Maryland five miles south of the Pennsylvania border. Exelon Corp., a utility, owns and operates the hydroelectric dam. Though Exelon’s operating license with the Federal Energy Regulatory Commission (FERC) expired September 1st, 2014, the company began the relicensing process in 2009, asking for a 46-year license agreement.

Complications ensued. Water quality studies were asked for, submitted, and questioned. FERC, which issued Exelon a provisional operating license, oversees the relicensing process. But a state law allows Maryland to require water quality protection measures.


Among the report’s highlights:

The dam has reached its storage capacity and spills sediment (aka sediment scouring) into the river during storm events.

Most of the pollution from the Susquehanna River to the Chesapeake Bay originates upstream of the dam as opposed to sediment and associated nutrients collected behind the dam.


“Our understanding is that Exelon needs a [state] water quality certification in order to get long-term relicensing,” says Lee Currey, director of the science services administration, Maryland Department of the Environment.

Currey outlined a timetable for that to happen:

In 2014, the State reviewed and denied Exelon’s application for certification on the grounds of insufficient information.

In 2015, the Lower Susquehanna River Watershed Assessment (LSRWA), a $1.4-million study conducted by the U.S. Army Corps of Engineers and Maryland Department of the Environment, was used to determine how sediment behind the dam impacts Bay water quality.

In addition, Exelon is funding two new studies: one by the University of Maryland Center for Environmental Sciences (UMCES) and the other by the U.S. Geological Survey.

In 2016 and 2017, the State will use study-generated information to analyze and evaluate the dam’s current condition and water quality.

In 2018, says Currey, “The State will be able to know if it will issue the water quality certification.”

McGee agrees. “The last outstanding piece for relicensing is the water quality certification. So 2018 is the driver in terms of timing,” she says.

The Army Corps of Engineers released a draft LSRWA report in 2014. Until further scientific studies are done, the report frames discussion of the controversy, according to McGee.

A final LSRWA report is due in 2015 or early 2016 but Bruce Michael, for one, doesn’t expect it to be much different from the draft. Michael, director of resource assessment service, Maryland Department of Natural Resources (DNR), served as that agency’s point person on the LSRWA team.

The report found, for example, that 13 percent of the sediment from the Susquehanna from 2008 to 2011 came from the dam versus 87 percent from sources in the river’s watershed.

The report also indicated that sediment itself was not the biggest danger to water quality but, instead, nutrients like nitrogen and phosphorous that attach to the sediment and encourage algae bloom. It concluded that the best long-term solution was pollution reduction upstream.

For Maryland, the Conowingo Dam controversy presents an additional complication. In 2010, federal officials mandated that the six Chesapeake Watershed states—New York, Pennsylvania, Maryland, Delaware, Virginia, and West Virginia—and Washington, D.C. develop Environmental Protection Agency-based pollution limits, or Total Maximum Daily Load (TMDL), and enforcement mechanisms.

The TMDL required that 60 percent of each jurisdiction’s allotment be in place by 2017, the rest by 2025. Maryland went beyond that timeframe, aiming for 70 percent by 2017 and 100 percent by 2020.

The timing puts Maryland in a quandary. Michael says that DNR agrees with the LSRWA report, and encourages the watershed states and D.C. to implement their TMDL strategies. But it also recognizes that even if they do so, “the state won’t meet its 2017 TMDL deadline if the dam’s sediment isn’t addressed,” he says.

None of the proposed options comes cheap. The LSRWA report estimated the cost of removing 25 million tons of sediment from the dam, to the 1996 level, at between a half-billion to three billion dollars. By one estimate, implementing the state’s TMDL would cost at least $14 billion.

“We don’t know if [sediment dredging] is a cost-effective strategy since nutrients appear to be more significant. It might be more cost-effective to reduce nutrients upstream,” says Michael, who is not alone in pondering the best use of funding.

Then, there is the question of who pays? “That is a separate issue,” Currey says of a cost that is likely to be split, in still to-be-determined amounts, among Exelon and state and federal governments.


Advocate for Dredging

Ron Fithian has a 30-year career as a waterman, from the Delaware to the Virginia lines. “I watched my livelihood go downhill year after year,” says Fithian, now a Kent County Commissioner.

The county was once the heart of the oyster industry, he contends. “But no one is oystering in Kent County and part of Queen Anne’s County, too. The oyster industry is the canary in the coal mine. Clams and aquatic grasses will follow.”

In 2012, Fithian founded and chairs the Clean Chesapeake Coalition, an association of seven Maryland counties–Allegany, Caroline, Carroll, Cecil, Dorchester, Frederick, and Kent.

The timing was not accidental. The coalition was formed after Maryland let the counties and Baltimore City devise their own Watershed Implementation Plans (WIPs), part of the state’s TMDL.

“There was sticker shock among local officials,” says Fithian, not least in Kent County whose WIP was estimated to cost $60 million, or almost 11 percent of its annual budget through 2025.

With the Conowingo Dam at sediment storage capacity and upstream states, Pennsylvania in particular, far behind on pollution goals, he says, the coalition advocates dredging as the most immediate and beneficial action.

“The dam needs to be dredged and [dredging] maintained on an annual basis to remove the sediment’s nitrogen and phosphorous before they come into the Bay,” says Fithian, arguing that environmentalists’ focus on chicken plants, agricultural practices, and waste water treatment is an unproductive approach.

The coalition has asked to participate in the state’s water quality certification hearings, says Charles “Chip” MacLeod, of the Chestertown law firm Funk & Bolton and coalition counsel.

“Maryland has to put conditions on Exelon to address the dam’s sediment. That doesn’t mean Exelon has to pay for it all,” says MacLeod. “We are at a pivotal point in the history of the Bay. If no conditions are put on the dam to clean up the sediment, we are doomed.”

Then Again…

Robert Judge, Sr., is mid-Atlantic regional manager, Power Communications, for Exelon. In an email answer to questions, Judge criticized the call for dredging the dam and cited the LSRWA report.

“Some are trying to inaccurately portray the dam as a source of pollution and are calling for dredging behind the dam to occur. The LSRWA…makes clear that not only is dredging prohibitively expensive (as much as $270 million per year), but that it will do little to actually help the health of the Bay,” he states.

As for the LSRWA report, Judge reiterated its findings about dam sediment versus upstream pollution. The report’s conclusion, he reminds, was that the Susquehanna River and the Bay watershed had “primary impact” on aquatic life and Bay health.

Calling Upstream

Emmett Duke, a former waterman, is the Sassafras Riverkeeper. The river runs along the dividing line between Cecil and Kent counties, only 10 miles from the Susquehanna and one of the first rivers to get water from it.

Once or twice every summer, Duke sees debris floating in the Sassafras—trees limbs, pieces of docks and 2 x 4s, not to mention Styrofoam cups and plastic bottles. “People are so used to it, they don’t even complain,” he says of the 500-member Sassafras River Association.

Duke said the debris come from the dam, thanks to rainstorms and spring thaws that cause seasonal flooding. The effect on Bay habitat is minimal. “It keeps washing down the Bay. It’s usually gone after the first tide or two,” he says.

Sediment is a different story. Duke points to 2011’s Tropical Storm Lee, where sediment scouring from the dam extended from the Sassafras to the Choptank River, 60 miles south.

“In a couple of hours, it went from nice clean water and a lot of fish to muddy water and a few fish,” he says.

But Duke doesn’t believe that dredging alone is the answer. “There’s nowhere to put the sediment plus it’s full of all sorts of stuff—nitrogen, phosphorous, pesticides, insecticides,” he says. “It’s a massive problem.”

Like Duke, Michael Helfrich sees a massive problem and no easy fix.

Helfrich has been the Lower Susquehanna Riverkeeper since 2005. His territory extends from central Pennsylvania to the Chesapeake Bay, and includes Harford and Cecil counties and pieces of Baltimore and Carroll counties.

“The beneficial part of the dam is over. It’s not trapping sediment, which is going into rivers and the Bay,” says Helfrich, a long-time activist for Bay clean-up who, echoing Duke, attributed debris in the rivers to flooding.

“The only thing I hold the dam responsible for is sediment scouring,” he says.

But that is an expensive proposition and Helfrich is worried, as are other activists. “The fear is that the State of Maryland comes to terms with Exelon through the water quality certification. Exelon pays an annual or lump sum to mitigate the situation,” he says.

“The money is used for environmental purposes but not necessarily to help the Susquehanna River. No dredging occurs. Nothing is done in Pennsylvania. In the long term, if Pennsylvania doesn’t get fixed, the Bay doesn’t get fixed,” Helfrich says.

Science to Answer

At UMCES Horn Point Laboratory, in Cambridge, Jeff Cornwell is on high alert. “My laboratory is a beehive of activity. We’re stepping over each other,” says Cornwell, a research professor.

And no wonder. Cornwell is conducting the State-required, Exelon-funded $1.2 million study that will be part of the water quality certification decision and, ultimately, Exelon’s relicensing. He plans to have the results available in 2016, in time for the State’s 2017 TMDL assessment.

The relicensing process has dragged on longer than usual because of questions about the Bay’s health, he says. There is a realization “that failure to take into account changes in Conowingo when it is full could endanger the whole Bay restoration program.”

Not everyone agrees with that, he adds, but enough do to spur his study. It will examine how much sediment comes into the Bay from the dam, where it is deposited and how much nitrogen and phosphorous are associated with the sediment.

In scientific terms, he will determine the bioavailability of the nitrogen and phosphorous to be transformed into algae. “No one has looked at the nature of the particles before,” Cornwell says.

Mike Roman is director of UMCES Horn Point Laboratory, under whom Cornwell works. A resident of the Eastern Shore, Roman is familiar with the dam’s fallout, including possibly sediment-filled “brown” water after 2003’s Hurricane Isabel and 2011’s Hurricane Irene, a rarity south of the Bay Bridge.

When it comes to Bay habitats, the State is primarily concerned about nitrogen and phosphorous from sediment becoming algae bloom, which reduces oxygen in the water.

Many State regulations are geared to increasing oxygen because, as Roman put it, “no oxygen, no fish, and no insects for them to eat.”

Roman said Cornwell’s research will answer key questions in the dam debate. “There have been complaints about the dam for decades. But it is only when relicensing came up that there was an opportunity to do something about it,” he states with some hope for clear resolution.