Guest Column

Water Quality Study Looks at Drainage Management as a Conservation Practice

By Meredith Smith, Communications Representative, Michigan Agriculture Environmental Assurance Program (MAEAP)

Every year, Western Lake Erie experiences algal blooms, some of which can be harmful to aquatic life and affect local drinking water. There are many factors causing harmful algal blooms, including nutrient-rich water from wastewater treatment plants, farm fields, the effects of invasive species, and the warm, shallow waters of the lake.

The Michigan Departments of Agriculture and Rural Development (MDARD) and Environment, Great Lakes, and Energy (EGLE) are working on one potential solution to reduce the amount of nutrients entering Lake Erie from farm fields. In partnership with Michigan State University (MSU), the two departments are conducting a five-year, edge-of-field water quality research project to investigate the benefits of water management as a conservation practice in reducing phosphorus loss from farm fields into the Western Lake Erie Basin watershed.

“This is the most comprehensive study of drainage management structures,” said Robert Day, Environmental Manager for EGLE. “We think the drainage structures have a lot of potential because they are reducing flows and holding water back on the landscape, which in turn reduces nutrient loading into the lake.” “The causes of algal blooms in Lake Erie are numerous and complex,” said MDARD Director Gary McDowell. “We know fertilizer from farm fields is one of the causes, and we are working to reduce the amount of phosphorus and other nutrients from entering the lake. This project will hopefully give farmers another tool to help take care of the environment, protect our waterways, and increase their crop yields by keeping much needed nutrients on their fields.”

For this project, three on-farm sites were selected in Lenawee County. Each site received two different conservation practices: one was a saturated buffer and the other controlled drainage. Since the project finished construction in 2018, baseline data has been collected on water quantity and quality at the drainage system outlets of each sites.

Controlled drainage is the practice of managing water in the field by changing the outlet level of the drainage system. This practice is used to reduce drainage water volume and nutrient load transport to surface water.

Saturated buffers store water within the soil of the field by diverting drainage water from the control structure (that raises the water table) into shallow perforated drains that run parallel to the ditch. This practice forces water to flow through the natural filter of the soil, so that contaminants can be removed.

“We are approximately halfway through the project,” said Dr. Ehsan Ghane, lead researcher on the project and Assistant Professor and Extension Specialist in the Department of Biosystems and Agricultural Engineering at Michigan State University. “We have implemented the controlled drainage system at two of the three sites. On October 1, we will be implementing the saturated buffer system on the third research site.”

Dr. Ghane and his team are collecting flow measurements and water samples at each site. It will take the rest of the project timeline to determine the effectiveness of the conservation practices in preventing nutrient loss and potentially improving crop yields. MDARD, EGLE, and MSU believe producer involvement in implementing conservation practices— specifically drainage management—in the Western Lake Erie Basin watershed is crucial to helping prevent harmful algal blooms. By reducing the amount of nutrients from farm fields into the lake, it will help reduce the production of potential harmful algal blooms. “We are encouraging farmer involvement because it is a win-win,” said Day. “We can reduce nutrient loads to the lake and they [farmers] can improve productivity, which is good for their bottom-line.” “This research is important for many reasons, including the well-being of the public, economy, recreation, tourism, and safe drinking water,” said Dr. Ghane. “It is important for agriculture because farmers care about the environment. They are motivated to help protect the environment as well as growing crops that feed us all.” The edge-of-field project will continue until 2022. For more information about the project, contact Dr. Ehsan Ghane at ghane@msu.edu. ■