Pumping water back through the same buried pipes used to drain wet fields could increase crop yields significantly while cleaning groundwater and providing a wetland wildlife habitat.

Results from three Agricultural Research Service test sites show corn yields went up nine to 60 bushels an acre, and soybean yields went up six to 11 bushels an acre, on average. During the drier growing seasons, corn and soybean yields went up by 48 and 40 percent, respectively.

The test sites have been in operation for six to seven growing seasons in Ohio.

Preliminary results show that water exiting the wetland had, on average, 75 percent less solids — organic matter and sediment, with pesticides possibly attached; 74 percent less nitrate from fertilizer and 63 percent less organic carbon. The wetland trapped the solids and organic carbon, and used the nitrogen to fertilize wetland plants.

Vegetation is thriving in the healthy wetland, providing cover for a variety of wildlife, with up to 19 species of dragonflies — indicators of good water quality — as well as waterfowl, including herons and mallards.