Monday, October 19, 2020

Put In Your Two Cents on Conowingo Dam

 Chesapeake Bay Magazine, Feedback Wanted on Conowingo Dam Action Plan

For the first time, a coalition of environmental groups have drafted a plan to clean up pollution from the Conowingo Dam that flows into the Chesapeake Bay. And they’re opening it up for public input.

The Conowingo Watershed Implementation Plan is meant to be a road map toward achieving a “pollution diet” similar to the one in place for the entire Chesapeake watershed. The goal is to reduce the nitrogen, phosphorous and sediment loads that wash downstream and harm marine life.

For decades, the Conowingo Dam functioned to trap nutrients, sediment, and pollution so that less of it traveled from the Susquehanna River and reached the Bay. But over time, sediment built up behind the dam, rendering it unable to trap any more pollutants. While the watershed states struggle to meet their cleanup goals for the Bay, it’s even more important to address the pollution at Conowingo Dam. This dam-specific Watershed Implementation Plan (WIP) zeros in on the specific problems it presents.
Conowingo Dam
“It has one focus: nitrogen,” explains The Center for Watershed Protection’s Bryan Seipp. The goal of the plan is to find the lowest cost solutions to eliminate six million pounds of nitrogen pollution entering waterways. The Conowingo WIP is a much-needed solution to a challenging problem that will build on, but not duplicate, the WIPs that states are already using to meet their existing goals.”

The WIP is a partnership between the Chesapeake Bay Program, Chesapeake Bay Trust, the Center for Watershed Protection, Chesapeake Conservancy, and a steering committee that includes all of the Bay states. Joel Dunn, President and CEO of Chesapeake Conservancy, promises the coalition will “track implementation and reward performance” to advance conservation and restoration goals. “We can do hard things,” he puts it simply.

The plan, more than a year in the making and funded by a $600,000 EPA grant, is open for public comment from individual residents, businesses, watershed groups and local governments, from now until December 21, 2020. You can submit comments and questions related to the draft WIP to To read more on the plan, visit the Chesapeake Bay Program website.
My view is that the sediments behind the dam should be used to rebuild Chesapeake Bay islands lost to erosion in part due to the lack of sediment coming down the Susquehanna as a result of the dam (admittedly, only a small part). I don't worry too much about the nutrients and toxics in the sediments. In properly reconstructed islands, only a small amount of the sediment will interact with the water, and a rational plan would use clean sediments for that portion.

The other problem would be the technical one, the problem of moving the dredge spoils over (or around) the dam.  I'm sure it can be done, but it might be expensive. How about a slurry pipeline to carry the sediments to the needed areas. Slurry pipelines work for coal.

1 comment:

  1. If this is anything like the issue of the Hudson River sediments of a decade or so ago, any attempt to dredge or disturb these sediments will turn loose a plethora of toxic pollutants that are currently effectively trapped and encapsulated (kind of like what is recommended for lead-based paints). Sometimes it is best to just leave sleeping dogs lay, until a good way to handle it can be proposed.