Response below submitted by Warren Formo, Executive Director Minnesota Agricultural Water
Resource Center (MAWRC). Minnesota Farm Bureau Federation is a member of MAWRC.
The recent article proclaiming that “unregulated farm tiling puts state’s waters at risk” provides helpful insights into the ongoing debates about agricultural drainage and water quality. The article contains a few nuggets of truth, along with some very inaccurate, incomplete and sometimes conflicting information.
We are one of only a handful of states that have wetland regulations at the state level. The author states that pattern tiling is largely unregulated but fails to tell readers how wetland regulations work. In Minnesota, drainage projects are reviewed by a drainage authority as outlined by our Wetland Conservation Act. Only after it is determined that there are no wetland impacts, or that any unavoidable wetland impacts are being mitigated through the creation of replacement wetlands, is the project allowed to proceed. As many as seven different federal and state agencies are involved in this process.
The author also opines that the purpose of pattern tiling is to move water as quickly as possible from farmland to the nearest ditch, stream or lake; and reinforces his notion with a diagram showing a tile system design. I see such diagrams as examples of better technology allowing drainage to be accomplished with less environmental impact when compared to drainage systems of the early 1900s. Those lines are not randomly placed. They are laid out to follow field contours, and when properly arranged and installed they contribute to one of the qualities referenced by the author, soil health.
Healthy soils contain both water and oxygen. Many of the most productive soils in the Midwest do not have the ability to drain naturally, starving the microorganisms in the soil of oxygen. This in turn affects nutrient cycling in the soil and can reduce crop productivity, which is important in returning organic matter to the soil to continue the cycle. Yields in Minnesota continue to set records due to many factors including better genetics, improved nutrient application practices, and improved drainage design that contributes to improved soil health.
The author describes water-level jumps of “five feet or more”, without noting that these jumps are largely driven by surface runoff, which is conveyed in the same channels as tile drainage but flow virtually without limits. I would gladly show the author some examples where more tiling coupled with changes in ditch and storage basins actually reduces peak flows.
Strategies to manage water is an important consideration of farmers. I would invite the author to join me on a few tours to see firsthand how innovations in tile installation and management are being employed on Minnesota farms. Perhaps this could lead to a more productive discussion about good drainage practices and promoting their application across more of the landscape, rather than broadly condemning a practice that in my experience is one of the biggest environmental success stories of the past quarter-century.