A Plan for Investigating the Effects of
Stream Restoration on Nitrogen Processing in
a Piedmont Valley in Baltimore County,
Paul Mayer, USEPA
The U.S. Environmental Protection Agency, the U.S. Geological Survey, and the Institute for Ecosystem Studies are collaborating on a multi-year investigation of the impacts of stream restoration on the processing of nitrogen in Minebank Run, a 3-square-mile watershed in the Towson area of Baltimore County, Maryland. The upper reaches of the watershed have been urbanized since the 1940ís, and the stream channel has undergone significant downcutting and widening. The channel network was restored in the upper third of the basin in 1998, and restoration is scheduled for the lower two-thirds in the summer of 2003. The restoration includes filling of reaches that have incised channels and installation of rock and wood structures that mitigate the impacts of increased velocities during high-flow conditions. The goal of this investigation is to determine the impacts of stream restoration on the physical and chemical processes affecting nutrient fate and transport in the stream channel and its underlying and adjacent sediments. The study is designed to investigate the hydrodynamics and hydrochemistry of this reach before and after the restoration.
During the study, both the stream water and near-stream ground water will be sampled and analyzed for nutrients and major ions. Wells will be installed along transects perpendicular to the channel. The transects will have wells in the stream channel and in the adjacent valley. The investigation will include research on supply and retention of carbon for denitrifiers and injection/recovery tests to determine the denitrification potential of the sediments near and under the stream channel.