ARS | Publication request: TREND DETECTION IN LAND USE AND WATER QUALITY DATA FOR THE HERRINGS MARSH RUN WATERSHED

Submitted to: Water Quality Symposium Proceedings
Publication Type: Proceedings
Publication Acceptance Date: September 28, 1998
Publication Date: N/A

Technical Abstract: Agricultural non-point source pollution has been of concern, particularly where intensive operations exist near environmentally sensitive waters. In 1989 the United States Department of Agriculture (USDA) addressed these concerns by funding eight Water Quality Demonstration Projects with the goal of increased voluntary adoption of agricultural best management practices (BMPs). The Herrings Marsh Run Demonstration Project in Duplin County, North Carolina has been able to document water quality improvements as a result of widespread BMP implementation. By combining the resources and expertise of various federal, state and local agencies and a receptive agricultural community, BMPs have been installed throughout the watershed to address several aspects of farm management and rural land use. Accurate land use data, that could be linked to the subwatershed water quality monitoring stations, proved to be the most difficult information to collect. Current government databases typically do not contain detailed records. Farmers, and in some cases contract growers, consider some information to be proprietary. Standard government records were supplemented with farm surveys and drive-by field observations to document land use changes. Water quality monitoring and USGS gaging stations were installed on streams in subbasins within the watershed to help characterize the overall water quality of the drainage area. In addition, by utilizing subbasins it was possible to compare and contrast changing land use patterns on the watershed. Water monitoring data from the watershed outlet have confirmed an improvement in water quality as evidenced by a 50% decrease in the nitrate-nitrogen (NO**3-N) concentration.