April 6, 2011

Speaking of dams

Conowingo Dam on the Susquehanna River
The recent "Damned If You Do; Damned If You Don't" article by Jody Argo Schroath in Chesapeake Bay Magazine opened my eyes WIDE. This is one of my favorite publications by the way.

I first saw the humongous Conowingo Dam on the Susquehanna River years ago and followed its damage in 1972 by Hurricane Agnes when I lived in Baltimore. But I never realized that it's only one of three hydroelectric dams on the lower part of that mighty river, the longest along the East Coast by the way. As a sailor, I don't get to explore some rivers thanks to dams. You can't portage a 36 foot sailboat. Damn! The dam used to be a problem to shad swimming upriver as well. But a $12 million fish lift was completed in the early 1990s and has restored more than 1 million shad to the upper Susquehanna.

The Conowingo Dam, which began generating power in 1928, is a big player in "nonpoint source pollution" prevention. It has trapped a bunch of nasty stuff behind its thick walls and flood gates that doesn't need to flow into the Chesapeake Bay. Schroath says, "an average of 3.5 million pounds of phosphorus and 2 million tons of dirt every year." Yes, every YEAR! So one third of the phosphorus coming from farms, lawns and other sources of "nonpoint source pollution" and half the sediment washed off farmed and developed tree-less terrain end up in Conowingo Pond. You might think that that's a good thing, but this pond does not have infinite capacity. Just how long before it's full? I hope Schroath can answer that in next month's issue.