In the United States more than 200,000 miles of waterways have been modified to trapezoidal-shaped drainage ditches benefiting more than 110 million acres of agricultural land at an estimated cost of $56 billion dollars. Agricultural ditches are designed to remove excess water from fields and prevent flooding onto fields. Often these ditches serve as the collection systems for subsurface drains that are located 3 to 4 ft below the ground surface. This necessitates headwater ditches being much deeper and wider than natural streams. Maintaining the important drainage function of these systems can require expensive maintenance, which removes sediment and disrupts the natural formation of benches, that can have adverse ecological and water quality impacts.
Researchers at the Ohio Agricultural Research & Development Center (OARDC) have developed a new "two-stage" ditch design. The new design has a small main channel at the bottom of the ditch - stage one - and grass-covered "benches" along the sides of the channel - stage two. The main (inset) channel provides some of the service of a natural channel. The benches provide some of the services provided by the floodplains of natural rivers and have water quality benefits. This design has increased drainage capacity so there is less flooding of surrounding farmland. It is also seeing application in urban area as a stormwater management practice.
More than a 100 two-stage ditches have been constructed around the world - in China, Illinois, Indiana, Michigan, Minnesota, Mississippi, New Zealand, Ohio, and Scandinavia. Stakeholder satisfaction has been very high. Joint research involving scientists at the OARDC and the University of Notre Dame has shown that the design reduces the export of nitrate-nitrogen from fertilizers into rivers, lakes and streams -- an added benefit that can save farmers money and improve water quality. The practice is an approved USDA-NRCS Environmental Quality Incentives Program (EQIP) Agricultural BMP in Indiana and Ohio.
Join Andy Ward, The Ohio State University; and Lisa Brush, The Stewardship Network as they present on this important stewardship topic.
Andy Ward - Professor in the Department of Food, Agricultural and Biological Engineering, The Ohio State University. He has a degree in Civil Engineering from Imperial College, England and degrees in Agricultural Engineering from the University of Kentucky. Andy is a registered Professional Engineer in Kentucky and has 35 years of international experience in the areas of watershed hydrology, stream geomorphology, reservoir sedimentation, modeling hydrologic systems, drainage, soil erosion, water quality, and the development and implementation of techniques to prevent or control adverse impacts of land use changes on water resources, streams and drainage networks. He has pioneered work on two-stage agricultural ditches. He is an advocate of student-centered learning and in his courses he incorporates teamwork, solving real world problems, applying engineering and scientific judgment, and enhancing communication skills. Andy is a co-author of the textbook Environmental Hydrology.
Lisa Brush - Executive Director, The Stewardship Network. Lisa has worked in the environmental field in Michigan for the last fifteen years. She is currently the Executive Director of the Stewardship Network and has been involved with the Network since its inception more than 10 years ago. She has a wealth of experience helping non-scientific people understand scientific issues. For over nine years, as she has built and coordinated The Stewardship Network, she has emphasized effective and meaningful stakeholder involvement in developing and implementing all aspects of this program. She has a M.S. in Natural Resources from the University of Michigan and a B.A. (Science in Society) from Wesleyan University.