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ANNAPOLIS – Exelon Power is negotiating a new 46-year license to operate the Conowingo hydroelectric generating dam on the Susquehanna River in northern Maryland, which provides power to more than 700,000 homes. The current license expires in September 2014.
But state officials and legislators from the Eastern Shore said Friday that sediment and fish passage issues need to be worked out first in order to better protect the Chesapeake Bay.
Sediment levels are one of three major contributors to pollution in the Chesapeake Bay, along with nitrogen and phosphorus, and more and more sediment has been passing through the Conowingo Dam in recent years, particularly during storms.
Legislators are frustrated by the amount of state money spent on sediment studies at the dam, when much of the sediment is flowing in from Pennsylvania.
Sen. E. J. Pipkin, R-Queen Anne’s, asked for an action plan to take the place of studies and meetings that have been going on for too long.
“Can we ask for a summit with Pennsylvania?” he said.
The Eastern Shore Delegation will be sending a letter to Gov. Martin O’Malley to make sure Pennsylvania is appropriately involved in the discussion.
Scientists have been aware of sediment issues at the dam since the 1970s, Maryland Department of the Environment Secretary Robert Summers said Friday, and efforts to decrease its flow with erosion and land conservation strategies have been working.
“We have seen a decrease of sediment flowing into the reservoirs,” Summers said. “There is progress being made.”
The Conowingo Dam is on the Susquehanna River about five miles from the Pennsylvania border and 10 miles from the Chesapeake Bay. Sediment that passes through the dam from Pennsylvania eventually reaches the bay.
The dam has historically been a great controller of sediment, Ann Swanson, executive director of the Chesapeake Bay Commission, told legislators Wednesday. Three million pounds of sediment reach the dam every year, and the dam only lets 1 million of that through, storing the other 2 million in reservoirs.
At equilibrium, when water levels on both sides of the dam are equal, all 3 million pounds of sediment pass through, Swanson said.
Equilibrium currently occurs only during storms. But studies show that as the dam’s storage capacity is used up, permanent equilibrium could be reached in the next several decades.
“So whether you believe that equilibrium is going to be reached in the next 10 years, next 20 years, or the next 40 years, it’s going to happen during the next license cycle,” she said. “So what that means is we better get the license right now, and we better negotiate whatever we can associated with sediment, associated with fish passage, associated with flow and land conservation.”
The dam, which has been producing power since 1928, is licensed by the Federal Energy Regulatory Commission, and both Maryland and Pennsylvania are responsible for issuing water quality certifications.
Federal and state agencies are working with environmental groups to study the inflow and outflow of sediment, and fish passage. The $1.38 million study uses computer modeling to determine whether and where to dredge, and whether it would be beneficial to let sediment through at times that would be less damaging to the bay.
Exelon is also participating in the study, which will be ready by 2014. But those parts of it that will be necessary for licensing negotiation will be available this year, said Frank Dawson, assistant secretary of aquatic resources for the Maryland Department of Natural Resources.
The dam cannot be the only stopper of sediment, Summers said. Maryland and Pennsylvania need to prevent sediment from entering the dam to begin with.
“The sediment issues require participation from multiple parties,” said Mary Helen Marsh, director of environmental operations for Exelon Power.
For all of the state resources going into resolving the sediment issue at the dam, sediment only seems to be increasing, legislators said.
“It’s time for some action,” said Delegate Jay Jacobs, R-Kent. “It’s time for some resolution. You can’t keep taking and not giving.”