Drainage water management systems allow a farmer to hold back water in the tile line after harvest and before planting, conserving water, increasing yields and retaining nitrogen.
Drainage water management (DWM) helps to control the amount and timing of water leaving agricultural fields through tile lines. DWM works by adding a water control structures to existing tile networks to raise or lower the water table to a desired elevation depending on crop needs.
DWM works best on flat land, and according to the Nutrient Reduction Strategy can reduce Nitrate-N loss through tile lines by an average of 33%.
“Properly managing my tile drainage allows my crops to take up the nutrients and water available in the soil.”
Bruce Rohwer, Farmer, O’Brien County Iowa
- Soil moisture management
- Decrease nutrient leaching
- Increase soil carbon (reduced oxidation of soil organic matter)
- Yield increase (estimated 50-70 bushels per acre of corn and 20-25 bushels per acre of soybeans)
- Estimated to cost $40 – $110 per acre (assuming land is flat enough for one structure to control 20 acres)
- Compatible with existing federal and state cost-share programs so farmers who implement them can recoup some of their costs
- Natural Resources Conservation Service (NRCS): General information from the NRCS on Drainage Water Management, including information on cost share and information videos.
- Transforming Drainage: A storing house for drainage water management research from a collaborative research group across 8 states.
- Webinar from Iowa State University Extension and Outreach: A webinar on Controlled Drainage from researchers Gary Sands, Tony Thompson and Matt Helmers.