Conowingo Cleanup Costs Estimated at $53 Million

Is that all? Bay Journal, Added cleanup for pollution behind Conowingo Dam will cost $53 million a year. Who will pay for it

The cost to reduce the added nutrient pollution spilling over the Conowingo Dam now has a price tag: at least $53 million a year.

That’s the rough estimate contained in a draft strategy aimed at finding ways to offset the additional nutrients passing though the dam to the Chesapeake Bay, now that the dam’s 14-mile long reservoir is filled with sediment.

The dam is located on the Susquehanna River in Maryland 10 miles upstream of the Bay. Most of the cleanup work proposed in the draft plan, released for comment Oct. 14, would take place upstream in Pennsylvania, primarily on farms.

The plan envisions attracting private investors to front the money needed to jump-start the work but said that will only happen if the states and U.S. Environmental Protection Agency commit to paying them back — something that has not happened so far.

Beth McGee, director of science and agricultural policy at the Chesapeake Bay Foundation, said she liked much of the proposed strategy, but said its success depends on whether the state-federal Bay Program comes up with a way to pay for it. “It’s only a plan,” she said. “If it doesn’t get implemented, we’re no better off.”

For reference, the cost of a single F35 Joint Strike Fighter is about 80 million. One flew over today at low altitude. 

The dam, completed in 1929, actually helped to reduce Bay pollution for decades by trapping sediments and associated nutrients. It’s long been known that the reservoir would eventually fill, allowing sediment and nutrients to flow more freely into the Chesapeake. When the latest Bay cleanup plan was drafted in 2010, though, that wasn’t expected to occur until after the 2025 deadline that states are striving to meet.

But that has already happened, and computer models estimate an additional 6 million pounds of nitrogen and 260,000 pounds of phosphorus now reach the Bay in a typical year.

That’s enough to keep the Chesapeake’s 2025 clean water goals out of reach.

With states already struggling to meet their individual pollution reduction goals, the Bay Program in 2018 decided to have an outside group develop a separate plan to offset nutrient increases from the dam and come up with a way to finance it.

Last year, the EPA awarded nearly $600,000 to the Center for Watershed Protection, Chesapeake Conservancy and Chesapeake Bay Trust to tackle the job.

“It’s a massive lift,” said Bryan Seipp, a watershed planner with the Center for Watershed Protection, who led the team. “It took decades and decades for this material to build up behind the dam. Trying to solve a problem that took decades to create in a fraction of that time is a challenge.”

The team examined nearly a dozen options, some of which included actions outside the Susquehanna watershed that would achieve the same benefits to the Bay, before settling on the recommended strategy. Most of the other options cost more — one came in at $368 million a year.

The lowest cost strategy came in at $49.5 million dollars annually but relied solely on reductions from agricultural lands in the Susquehanna basin. Seipp said that raised concerns that an overreliance on agriculture would result in taking too much farmland out of production.

Hey, we don't need to eat or anything. 

The selected plan focuses entirely on the Susquehanna watershed — primarily in Pennsylvania. It also identifies places where nutrient control actions would be most effective and suggests more than a dozen on-the-ground pollution control practices that would be the most cost-effective to implement.

The plan still relies mostly on agriculture, but also seeks a sliver of nutrient reductions from developed lands.

The strategy cautioned, though, that its estimated costs are “likely low.” They do not include, for example, the cost of providing technical support staff to work with landowners on runoff control practices.

The draft also opened the door to other alternatives, such as dredging built-up sediment from behind the dam. Maryland is planning a pilot study to determine whether that is feasible.

I would try to find a way to use the dredge spoils to rebuild Bay Island that are eroding, like Baltimore Harbor dredge spoils are used to recreate Hart-Miller Island and Poplar Island. We have plenty of islands that could use the help. They could even stop whining about Smith and Tangier Islands disappearing, and actually do something about it.