Three years of crop yield using drainage water management in Ohio

Drainage water management (NRCS-Practice Code 554) is an important agricultural water management practice for dealing with nitrate-loading to surface water across the Midwest US. There may also be a positive crop yield benefit. A three-year demonstration project was conducted in Ohio to evaluate the effects of drainage water management on crop yield. We installed water table control structures (WTCS) in fields with subsurface drainage. At each demonstration farm we had two zones; one for subsurface drainage only, and one for controlled drainage or drainage water management. Thus, a side-by-side comparison between conventional subsurface drainage and drainage water management was performed. Both zones at a farm had similar topography, cropping and nutrient management, etc. Results for corn indicated that drainage water management significantly improved crop yield by 1 to 19% in six out of nine observations at these demonstration farms over the three growing seasons. Results for soybean indicated that drainage water management significantly improved crop yield by 1 to 7% in seven out of eleven observations over three growing seasons. After three years of growing corn and soybean crops at our demonstration sites on private farms, it appears that the crop yield benefit is variable and may be related to the topography of the field, the amount and timing of precipitation as well as type of crop being grown; corn or soybean. Continued evaluation and expanded research is warranted.