ARS | Publication request: Assimilation of agrichemicals and sediments in runoff within drainage ditches and constructed wetlands

Submitted to: Proceedings of the American Society of Agricultural and Biological Engineers International (ASABE)
Publication Type: Proceedings
Publication Acceptance Date: July 10, 2006
Publication Date: July 10, 2006
Citation: Cullum, R.F., Moore, M.T., Cooper, C.M. 2006. Assimilation of agrichemicals and sediments in runoff within drainage ditches and constructed wetlands. Proceedings of the American Society of Agricultural and Biological Engineers International (ASABE). Presented paper #062004 at 2006 Annual Meeting.

Interpretive Summary: Herbicides like atrazine are found in runoff from agricultural fields. Before this atrazine enters into lakes and streams, it can be processed in ditches and wetlands. A study on how long of time the herbicide atrazine would need to be in the ditches or in the wetland before it was reduced to levels unharmful to the environment was conducted. Results showed from 6 to 48 days would be required dependent on both length of the flow path and initial concentration of atrazine. These results will be useful to extension personnel, action agencies involved in water quality planning, and to farmers who plan to manage ditches to reduce atrazine that leave the farm fields before entering streams and lakes.

Technical Abstract: Atrazine was amended into an agricultural drainage ditch and constructed wetlands for the purpose of monitoring transport and fate of the pesticide. Aqueous half lives of 6 and 16 to 48 days in drainage ditch and constructed wetlands, respectively, were found. Flow paths of 50 m and 103 to 281 m were required to mitigate atrazine in the drainage ditch and constructed wetlands, repectively. This information provided design parameters for ditches and constructed wetlands to mitigate the herbicide in agricultural runoff.