What is an Agricultural Buffer, and How is it Flexible?
Agriculture is one of two predominant land uses in the Nanticoke Watershed, comprising 45% of total land use. Runoff from farms can contribute significant amounts of nutrients like nitrogen and phosphorus to local waterways, groundwater, and ultimately the Chesapeake Bay. With little forward movement on the Chesapeake Bay Agreement to reduce pollution and protect this ailing national treasure (2000), agriculture has been receiving a lot of attention and the Environmental Protection Agency (EPA) is seeking widespread implementation of “best management practices” (BMPs) to reduce agricultural runoff into the Chesapeake Bay watershed. The Nanticoke Watershed Alliance implemented a program to study the use of flexible buffers in 2010-2012.
Buffers are strips of vegetation along drainage ditches that help to capture nutrients before they run off into the ditches after a rainfall. Without any buffer system, agricultural ditches are capable of transporting high amounts of excess nutrients into local creeks and rivers that lead into the Chesapeake Bay. However, in our watershed, many ditches are on lands with prime agricultural soils, making planting wide buffer strips, that would consume large amounts of productive cropland and ultimately reduce the overall yield and potential income for farmers, a difficult option.
“Flexible” agricultural buffering just means that the width of the buffer strip can be adjusted but does not meet Conservation Reserve Enhancement Program (CREP) standards. Our monitoring program was to test the hypothesis that any size buffer system is better than none at all.
The Nanticoke Watershed Alliance, Dorchester Soil Conservation District, and Wicomico Soil Conservation District partnered with farmers in small watersheds of the Nanticoke River system to plant flexible-width buffer strips of native grasses along their drainage ditches. The purpose of this pilot was to gauge the feasibility of providing moderate economic incentives to farmers to plant and maintain a narrower-width buffer where current CREP provisions are difficult to implement.
Throughout the year, the Alliance also performed water quality assessment by collecting bi-weekly samples at six sites within one sub-watershed, focusing on the analysis of nitrogen and phosphorus levels that were present in the ditches and river system. This pilot project used the same data management and assessment protocol as our EPA-approved Creekwatchers Program.