Riparian forest buffers of the Susquehanna-Chesapeake Watershed: observations, assessments, and recommendations

USDA’s Conservation Reserve Program (CRP) is the nation’s flagship private-land conservation program and has played a critical role in state and federal efforts to improve the health of the Chesapeake Bay. In the six states contributing to the Chesapeake Bay watershed, CRP has funded over 20,000 riparian (stream area) buffer contracts. To evaluate the performance of riparian buffers in the Chesapeake Bay watershed, a “One-USDA” project was implemented (USDA’s ARS, FSA, NRCS, FS) with support from a broader consortium of researchers that included scientists from US Geological Survey and Penn State. Led by LTAR’s Upper and Lower Chesapeake Bay sites, this study found that riparian forested buffers reduce nitrogen pollution by 17 to 56%, and phosphorus pollution by 4 to 20%, while riparian grass buffers were roughly equally effective. However, filtration of runoff by riparian buffers is regularly undermined by gullies and ditches that route runoff water around buffers, reducing the potential for buffers to treat runoff from adjacent lands by an average of 37% across the study area. Findings point to the need to bundle conservation practices, and programs, to optimize the performance of riparian buffers.