Think globally, act locally: Woodchip bioreactors help farmers reduce nutrient runoff - U of I Extension

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Think globally, act locally: Woodchip bioreactors help farmers reduce nutrient runoff

Think globally, act locally: Woodchip bioreactors help farmers reduce nutrient runoff

 

September 29, 2017

By Becky Buckrop

The excitement was palpable at Todd VerHeecke’s farm in Geneseo on Wednesday, September 27 as farmers, agriculture industry representatives, TV and radio news, and even a French media station gathered to see a woodchip bioreactor being installed.  The installation was part of a joint effort across Illinois agriculture to reduce nutrient loss in farm fields.

And for good reason.

High levels of nitrogen and phosphorous runoff from Illinois farm fields makes its way into the Mississippi River basin and has been a significant contributor to the Gulf of Mexico dead zone, an area low in dissolved oxygen.

VerHeecke is among those farmers who wants to protect our natural resources and water quality. “I wanted to leave my farm better than I found it for future generations. This bioreactor will help make sure that the water that leaves my fields has the nitrogen removed before it enters the watershed.” His fields feed into the Mississippi basin via the Green and Rock Rivers.

 
A crowd watches as the installation gets underway.

As Paige Buck with the Illinois Natural Resources Conservation Service (NRCS) explained, over 40 percent of land in the United States is farmland, making farmers more connected to our environment than any other group. “How they manage their private lands can have a big impact on our global environment.” Buck said.

Lauren Lurkins, director of natural and environmental resources for the Illinois Farm Bureau, welcomed the group and explained how the Farm Bureau has been working in collaboration with the NRCS, University of Illinois College of ACES, and the Illinois Chapter of Land Improvement Contractors of America on edge of field practices that capture and treat nutrient runoff.

 
Todd VerHeecke, left, in green, visits with contractors as they prepare to complete the bioreactor installation.

The goal is to better understand all that is being done right now and how to build on the current success to achieve the ultimate goal of a 45 percent loss reduction in both nitrate-nitrogen and total phosphorous by 2035. The focus is on reducing nutrient losses to the environment, not on reducing nutrient use for Illinois agriculture.

Ruth Book, sate conservation engineer with the NCRS, said they can work with farmers to devise a plan that is best suited for their fields. The NRCS will provide the standards, specifications, and design input for each particular farm. They can also provide incentive payments to help cover some of the costs of the bioreactor, helping farmers use best management practices to protect their natural resources and improve water quality. 

To install a woodchip bioreactor, a pit is dug where the main tile line drains from the field. The pit is lined with plastic and the existing drainage tile pipes are attached to a bypass flow to redirect the water so that it will go through the woodchips, which fill the pit. Bacteria on the woodchips convert the nitrate in drainage tile water into harmless nitrogen gas. This filtered water then flows through the diverted drainage pipes into the waterway. What makes these woodchip bioreactors so appealing is that they’re minimally invasive nature. They can fit on less than a quarter of an acre and are placed on the edge of field to minimize the loss of production acres.

 
University of Illinois College of ACES researchers Hannah Dougherty, left, and Jack Mrozek will monitor the water quality of the woodchip bioreactor under the direction of Laura Christianson, assistant professor of water quality.

The woodchip bioreactor at the VerHeecke farm will be part of a study conducted by Laura Christianson, assistant professor of water quality at the University of Illinois Deptartment of Crop Sciences. Her research assistants, Hannah Dougherty and Jack Mrozek will visit the site about once each month to conduct the tests on the water quality, monitoring the water’s flow rate and nitrate concentration. The flow rate is calculated from a pressure sensor that records the water depth every 15 minutes. These water samples will be analyzed for nitrate concentration in a laboratory on campus.


Video of the installation by Todd Gleason

Ivan Dozier, assistant state conservationist with the NCRS said, “With partnerships like these and the farmers who are willing to make the changes, we can have an impact on reducing nutrient losses, improving our environment and water quality for everyone.”