A $5 million federally funded project is reviewing potential costs and benefits of on-farm water storage to irrigate crops when necessary and keep excess nutrients from draining into waterways.
Jane Frankenberger, a Purdue professor of agricultural and biological engineering, is directing the five-year research program.
She said both the need for irrigation in late summer and issue of nutrients running off farm fields will be exacerbated by climate change. "This research will collect data now that will help farmers make better decisions in the future," she said.
Three practices have been proposed to address problems of crop loss from drought and degradation of water quality from drained farmland, which comprises about 25% of U.S. cropland:
Drainage water management: Unlike conventional drainage systems, this practice conserves water by increasing its retention time in the soil profile, thereby delaying or reducing the draining of soil water.
Saturated buffers: These store water within the soil of field buffers by diverting tile water into structures that raise the water table and slow outflow. Early results of a study indicate they can be effective in removing nitrate from tile drain water before it is discharged into surface waters such as streams.
Reservoirs: With this "capture and use" system, subsurface drainage water is diverted into on-farm reservoirs, or ponds, where it is stored until it is needed to irrigate crops.
The researchers say each of the practices has been evaluated in some areas, but findings have not yet been brought together and made into tools to improve decision-making.
The project will integrate research, Extension and education to bring new understanding, tools and strategies to increase resiliency of drained agricultural land.
Extension and education programs will extend the strategies and tools to agricultural producers, the drainage industry, watershed managers, agencies and policymakers. They also will help to educate the next generation of engineers and scientists designing drainage systems that include storage in the landscape.
The research is funded by the U.S. Department of Agriculture's National Institute of Food and Agriculture.
Other universities involved are Iowa State University, North Dakota State University, Ohio State University, University of Missouri, North Carolina State University, South Dakota State University and the University of Minnesota, as well as the USDA's Agricultural Research Service.
Other Purdue researchers working on the project are Laura Bowling, associate professor of agronomy; Bernard Engel, professor and head of the agricultural and biological engineering department; Eileen Kladivko, professor of agronomy; and Linda Prokopy, associate professor natural resource social science.
A video discussing the project is below.