3 takeaways from the Conservation Drainage Network’s annual meeting

A bioreactor at the Southwest Research and Outreach Center (SWROC) in Lamberton, Minnesota.

By: Lindsay Pease, Extension drainage specialist

Once a year, university researchers from around the country get together with state and federal agency staff and industry partners to discuss all things related to conservation drainage. This year’s meeting took place in early April at the University of Illinois. The goal of the Conservation Drainage Network’s annual meeting is to come together to discuss the latest research findings and different strategies to increase implementation of conservation drainage on the landscape. Here are three of my key takeaways from the meeting.

What is conservation drainage?

First, if you’re new to the term “conservation drainage,” here is a quick summary. Conservation drainage refers to a suite of practices that can be used in tandem with subsurface drainage systems to minimize environmental impacts while maintaining their capacity to remove excess water from the root zone. Some examples of conservation drainage practices include controlled drainage, denitrifying bioreactors, saturated buffers, two-stage ditches, and phosphorus removal structures. Many conservation drainage practices are incredibly effective at reducing nitrate losses from subsurface drainage systems, and can be cost-shared through the NRCS. For more detailed information on these practices, I highly recommend “Ten Ways to Reduce Nitrogen Loads from Drained Cropland in the Midwest” from the University of Illinois as a place to start.

#1 Implementation succeeds through partnership

Although conservation drainage has been around for many years, installation of new practices remains limited. We heard from several programs that are working to increase implementation in their local watersheds.

One notable example is Iowa’s “Batch and Build” Program. This groundbreaking program removes barriers to installation by coordinating across sites and landowners, and has led to more than 130 new conservation drainage practices installed in one county alone. This model is being replicated across Iowa and may soon be expanding to other states.

In Minnesota, the Board of Soil and Water Resources is prioritizing conservation drainage implementation through initiatives like its Water Quality and Storage Program. This program recently expanded to include funding to install conservation drainage practices that will help reduce nitrogen and phosphorus loss to Minnesota waterways.

#2 Water quality benefits without sacrificing agricultural production

Many conservation drainage practices originated from the need to reduce nitrate loads from subsurface tile drainage. When we install a practice at the end of a subsurface drainage system, a major concern is that it will negatively affect yield. We heard an update from a multistate team of researchers (Jane Frankenberger, Purdue University; Laura Christianson, University of Illinois; Tyler Groh, Penn State University; Morgan Davis, University of Missouri; Steven Hall, University of Wisconsin) who summarized the potential impacts of conservation drainage on air quality, water quality, and crop yield. The preliminary findings of this group show that conservation drainage delivers water quality benefits without any detrimental effects on crop yield or air quality. This team is expecting to publish the findings of their work later this year, and you can access a recording of the presentation here: ABCD: Accruing Benefits of Conservation Drainage.

#3 The future of conservation drainage is its ability to increase water storage on the landscape

In the past year alone, Minnesota has faced both catastrophic rain events and extreme drought. The time-sensitive nature of agricultural operations makes subsurface drainage necessary when we experience heavy rains. However, conservation drainage is based on the philosophy of draining every drop of water you need to produce a healthy crop – but not a drop more. We can use practices like controlled drainage to reduce drainage discharge when fields are fallow or once crop roots are established. We can also pair drainage and irrigation together to design a drainage water recycling system.

During the meeting, we heard a preview of a forthcoming report on the economic benefits of drainage water recycling systems from Chris Hay (Hay Water Solutions) and Chuck Brandel (ISG). Benefits of these systems go beyond increases in crop yield to provide benefits to water quality, wildlife habitat, and flood mitigation. You can access a recording here (skip to 29:23 for this presentation): Research and Discoveries Session Recording.

Learn more about conservation drainage

Learn more and join the Conservation Drainage Network: conservationdrainage.net. You can also access video recordings of presentations from the 2025 annual meeting (and past meetings) on the website.

Subscribe to the Agricultural Drainage Management Coalition’s weekly email newsletter to stay up to date on the latest in conservation drainage.

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