Agricultural drainage is an important management tool for crop production in many areas of Iowa. The design, installation and maintenance of drainage systems is the focus of the Iowa Drainage School on Aug. 20-22 at the Borlaug Learning Center on Iowa State University’s Northeast Research and Demonstration Farm, near Nashua.
“The Iowa Drainage School provides educational opportunities for all who are interested in drainage, whether they are contractors, farmers, consulting engineers, county officials or others,” says Matt Helmers, professor and ag engineering specialist with ISU Extension. “The school focuses on the fundamentals of drainage design, including getting an accurate survey, drainage pipe size and spacing, controlled drainage and water table management, legal considerations, and different installation techniques and equipment.”
Design, installation and maintenance
The three-day school features classroom lectures and discussions combined with team problem-solving and field exercises. Student teams will survey and design a drainage system for a sample area of the host farm, using concepts learned during classroom discussions. By attending this school, participants will be able to plan and lay out subsurface drainage systems and work out project costs. In-field equipment and drainage tile installation demonstrations will also take place.
Registration is $350 per person if registered by midnight Aug. 9. Late registration is $400 and must be received by midnight Aug. 16. Class size is limited to 40 participants, and preregistration is required. Registration includes meals indicated on the agenda, refreshments, course notebook and drainage reference materials.
Planning subsurface drainage
A successful tillage drainage system takes time to plan and install, and a number of factors need to be considered. “Key things needing attention when planning a subsurface drainage system include laws, soils and topography, capacity and intensity, installation quality, and environmental considerations,” says Kapil Arora, ag engineering field specialist with ISU Extension.
“Drainage contractors, engineers and consultants, landowners, farmers, agency staff, and others interested in subsurface drainage should not only pay attention to these key features, but also develop an understanding of how subsurface drainage systems function,” he adds. “When developing a plan, it’s helpful to consult a number of sources, beginning with a visit to your local soil and water conservation district office.”
Why install drainage? Planned installation of a tile drainage system can help protect crops from excess rain events, improve crop productivity, reduce yield variation in a field, and provide for more timely field operations.
When addressing water quality improvements for subsurface drainage water, no one practice may be able to achieve the desired reductions. A combination of both in-field and edge-of-field practices will be needed at field-scale, sub-watershed scale and watershed scale, Arora says. A comprehensive approach for reducing nutrients, as outlined in the Iowa Nutrient Reduction Strategy, can deliver a better impact in reducing nitrate-N concentrations and loads in subsurface drainage water.
Additional information on planning and designing a drainage system can be obtained from the Iowa Drainage Guide, available from ISU’s Extension Distribution Store. ISU conducts farmland drainage workshops and the annual Iowa Drainage School for stakeholders interested in farmland drainage. For more information on farmland drainage, visit agwatermgmt.ae.iastate.edu and extension.umn.edu.