This is the time of the year when decisions can be made on adding new subsurface drainage, or replacing older systems. When considering a new system, you might want to think about an alternative system design, a Drainage Water Management System. All of the benefits that come with a traditional subsurface drainage system can be achieved with a drainage water management system, plus at least one important extra.
Drainage Water Management (commonly called controlled drainage) provides improved water quality benefits. Recent research from across the Midwest United States shows that with drainage water management, annual nitrate-nitrogen loads can be reduced by as much as 50%. In addition, Ohio research suggests crop yield increases of 3% to 4% are possible on average, and maybe more in some cases and in some years.
Drainage water management systems may differ from traditional subsurface drainage systems as follows: 1) drainage laterals are installed on or near contour; 2) a water control structure is installed at the drainage outlet; and the outlet elevation can be raised to retain some of the drainage waters, and lowered to allow excess drainage water to be released; and 3) system layout may be designed to optimize drainage water retention by constructing water management zones, each with a separate water control structure. Of course, there may be other differences, along with pros and cons to each system. Want to know more?
Consider attending the 2015 Overholt Drainage School to be held March 16-20 in Defiance County. Several sessions are being planned: 1) Subsurface drainage: design, layout and installation; benefits and impacts; 2) Drainage water management (controlled drainage), design, layout and installation, management, benefits; 3) Water table management w/subirrigation: design concepts, operation and management, benefits; and new this year is 4) Drainage water harvesting, water for agriculture.
The Overholt Drainage School is a five-day, intensive course and is open to anyone interested in advancing their knowledge of basic concepts, principles, and skills related to the purpose, design, layout, construction, and management of soil and water conservation systems, with emphasis on agricultural water management and water quality. For more information, please contact Larry C. Brown at 614-292-3826 or firstname.lastname@example.org.
The Overholt Drainage School is sponsored by the Overholt Drainage Education and Research Program, Food, Agricultural and Biological Engineering, OSU Extension, OARDC, The Ohio State University in cooperation with the USDA-NRCS, USDA-ARS, Soil and Water Conservation Districts, Ohio Land Improvement Contractors and Associates, and others. Excellent drainage workshops are also conducted in Illinois, Iowa, Missouri, Minnesota, South and North Dakota.