May 6, 2013
Link to Southeast Farm Press Article
There's a new, better way to dig a ditch — one that's good for both farming and the environment — and it sprang from the mind of an Ohio State University scientist.
Andy Ward, an agricultural engineer in Ohio State's College of Food, Agricultural, and Environmental Sciences (CFAES), knows the benefits of conventional ditches, which are trapezoidal — or roughly V-shaped with a narrow, flat bottom — in cross-section.
They carry excess water from farm fields and in doing so benefit food production.
But he's also seen their drawbacks. Often, they're too big for small stormwater flows and too small for big ones.
They require expensive upkeep by landowners — mowing and plant removal that in Ohio costs about $450 per mile per year. And their upkeep exposes the ditch bank to erosion and destroys the plants and animals that live there.
Enter Ward's "two-stage" ditch design, which earned him the Ohio Agricultural Research and Development Center's (OARDC) 2013 Innovator of the Year Award. The award honors innovation and entrepreneurship by OARDC scientists. The center is CFAES's research arm.
The new design has a small main channel at the bottom of the ditch (stage one) and raised, grass-covered "benches" along both sides of the channel (stage two).
The benches catch any overflow from the channel, are high and wide enough to keep heavy rain runoff from topping the banks and flooding surrounding farmland, and serve in the same way as a natural river's floodplain.
Changing concept of good ditch
"The concept is changing long-held perceptions of what constitutes a 'good' drainage ditch," one of Ward's nominators wrote.
The idea "was developed by observing the natural processes of stable streams and rivers that could relieve erosion, scouring and flooding," OARDC said in a statement.
Since Ward and his team created the new design — he notes the contributions of colleagues Dan Mecklenburg, Jon Witter, Jessica D'Ambrosio and others — it's been used to build 20 drainage ditches around the Midwest. Thirty more have been built by Ward's former students and graduates of his design workshops. So far, none of the 50 has needed any maintenance.
The National Engineering Handbook of the U.S. Department of Agriculture's Natural Resources Conservation Service recognizes the design as an agricultural best management practice.
The design is currently eligible for federal cost-share through USDA's Environmental Quality Incentives Program.
Joint research involving Ward and scientists at 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 Army Corps of Engineers also has proposed building several miles of two-stage ditching to try to stop recurring flooding problems in Findlay in northwest Ohio.
The new design, the same nominator wrote, is "an alternative solution that provides substantial benefits to individuals and society."
Ward is a professor in CFAES's Department of Food, Agricultural and Biological Engineering, where he holds appointments with both OARDC and Ohio State University Extension. OSU Extension is the college's statewide outreach arm.
To view a video of the innovative ditch, see https://ag.purdue.edu/aganswers/Pages/archive.aspx?story=183 - .UYeg3mDBDBQ