"Pits use wood chips to remove nutrients from ag runoff before it reaches streams".
"Drew Koslow spent nearly two decades working with federal and state governments, as well as nonprofit agencies, to improve water quality in the Chesapeake Bay. He patrolled rivers, filed lawsuits against polluters, worked with landowners to put in practices that would treat stormwater and helped farmers control their runoff.
But in recent years, Koslow began to notice that while a lot of agencies talked about cleaning up the watershed, not a lot of people were helping to install the practices that would actually do the job. So he began doing that himself, securing state and federal funds to put in structures on farms that would reduce nitrogen and phosphorus flowing into waterways.
Over the last two years, Koslow installed six bioreactors on farms in the Choptank River watershed, where he served as riverkeeper. Bioreactors are a relatively new technology. Researchers at the Iowa State University lab in Ames, IA, began developing them just six years ago, though they were in New Zealand and Canada in the 1990s."