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Farmers and Rural Communities Unite In Battling Nitrate Pollution

posted on May 23, 2014

Late this week, Congress passed the Water Resources and Development Act of 2014 and sent it to the president for his signature. The measure plows a little more than $12 billion into flood control projects, improvements to U.S. ports and expansion of Mississippi River locks and dams.

While the improvements to the Big Muddy’s infrastructure will help move more grain it won’t do anything to stop Midwestern nitrates from reaching the Dead Zone in the Gulf of Mexico.

Row crop farmers usually get a black eye from environmentalists for the higher nitrate levels. But in one major grain producing state, growers and environmental watchdogs find themselves working together to protect and improve water quality. In this second installment of a two part series examining the issue, Paul Yeager discovered the partnership is yielding results.


According to Iowa Department of Natural Resources, 30 percent of the 880 municipal water supplies in the state of Iowa are highly susceptible to contamination from nitrates.  While there are many contributors, agriculture is often viewed as the primary source. 

Sec. Bill Northey, Iowa Department of Agriculture:  “We’ve seen some places in the country where the federal government has stepped in and try to regulate pieces around water quality with not a lot of success and certainly not near the size of any area that we’re talking about in the Mississippi River Basin or Iowa itself.”

In October of 2013, lawmakers in Iowa allocated an additional $22.4 million, doubling support to conservation and water quality improvements.  $2.8 million was earmarked for a cost sharing program designed to help farmers implement nutrient reduction strategies that include planting cover crops. 

Sec. Bill Northey, Iowa Department of Agriculture:  “We can do better and if we focus on this, I think we’ll get more tools and will figure out better ways of doing it that holds off the federal government from addressing this.  I think this is a better more effective way to make that happen, rather than have someone thousands of miles away in an office someplace draw a circle on a map and say, “Everybody does this in a certain area.” We need that flexibility.  We need I think the ingenuity of producers.”

The Iowa Nutrient Reduction Strategy, the culmination of two years of work by the Iowa Department of Agriculture, the Iowa Department of Natural Resources and Iowa State University, found that cover crops were the best single practice farmers could implement to reduce pollution from nitrates.  In Griswold, Iowa it is hoped cover crops planted in the wells capture zone will be the solution to reducing high nitrate levels in the cities water supply.   

Brent Bierbaum, Griswold, Iowa:  “We have family and friends that live in town so we need to do what we can to protect the groundwater there also.  And our wells come out of that too so we need to protect what we drink also.”

Brent Bierbaum farms 2,500 acres of corn and soybeans near Griswold, Iowa, He planted rye grass as a cover crop after the harvest but his neighbor Kenny Cousins applied seed to standing corn. 

Kenny Cousins, Griswold, Iowa:  “We flew rye on September 3rd and we got some nice rains after that and we've got some good germination on the seed and I think it's probably four or five inches tall out there now.”

While there are risks and costs involved with aerial seeding there are benefits.  Aerial seeding makes it possible to plant large areas quickly.  It also extends the growing season because it allows the cover crop to be planted prior to harvesting the cash crop.      

Ralph Storm, Storm Flying Service:  “If we get some fall rains this stuff take right off.  The rye is an amazing little kernel that will turn itself around and put a root down so easily.  And holding those nutrients available so they don’t get away from the farmer should be a real plus for everybody involved.   

While Bierbaum and Cousins planted rye as a cover crop in Griswold, just down the road Max Potter planted a combination of oats turnips.

Max Potter, Griswold, Iowa:  “The cover crop we've got here is oats and turnips.  We put it in where we chop.  This is I guess the first year we've done that.  And with all the interest in cover crops right now we thought we would try it.”

Oats as a cover crop deters weed growth, while turnips, described by some as cow candy,  prevents soil compaction. 

Max Potter, Griswold, Iowa:  “When we get the rest of this crop out then we'll pasture the cows in here too.  So it serves as a dual purpose.  It provides us with cattle feed as well as helping with erosion and stuff.  So the better we can take care of stuff and hold it here and hopefully not get it into the soil or down into the water system the better off everybody is.  So it's not just for us but the community and the country I guess you’d say.”

Cover crops aren’t the only cost effective solution municipalities are employing to keep agricultural run-off from entering water supplies.  In Elliott, Iowa, with a population of only 350 people, a $300,000 to $1,000,000 nitrate removal facility was out of the question.  The solution decided upon did not involve planting cover crops but instead to take cropland out of production. 

Steve Howell, Mayor Elliott, Iowa:  ” And we talked, the committee, we voted on it and this is what we decided, to try to do it naturally and have a wetland and this will be more permanent on the outcome.”

The city purchased 18 acres of marginal farmland and along with 4 acres donated by the school district, was able to construct a 22 acre wetland.  While the primary goal of the wetland will be to filter nitrates out of the town’s water supply it will also be a gathering place for the community.  Walking trails have been constructed and the wetland will be used by the school it borders as an outdoor classroom for environmental education.     

Deb Karwal, Montgomery County Naturalist:  “It’s a neat project.  I can’t even tell; you how amazing it is.  With our new electronics world, children don’t go outside any more.  They don’t touch living things.  And this is an outstanding way to incorporate core standard class room curriculum and bring it out here, outside where it’s more hands on.  And you can see these kids have been working on that for probably an hour now, and they’re still quite intrigued and enthused and curious as to what little things are in their tubs of water.”  

While it is too early to assess a change in nitrate levels in Elliott, in Remsen water monitoring tests have shown great results after the town of 1,600 converted nearly 100 acres of cropland to native grasses.

Becky Ohrtman is the Source Water Protection Coordinator for Iowa’s Department of Natural Resources. 

Becky Ohrtman, Source Water Protection Coordinator - Iowa DNR:  “Right now we know that if you plant native grasses in an area that is highly susceptible to anything on the surface as far as nitrate application or manure, anything like that, we know that native grasses work.”

Prior to planting native grasses the city's water at wellhead #8 showed nitrate levels at nearly 3 times the 10 parts per million considered safe.  Three years after seeding a 100 acre prairie, test results indicate nitrate levels have been reduced by 40% at well head 8 and 30% overall. 

Becky Ohrtman, Source Water Protection Coordinator - Iowa DNR:  So for the community of Elliott, a wetland, that worked for them.  For Griswold, cover crops work for them.  For Remsen, Iowa, putting in native grasses, converting crop land to native grasses worked for them.    So what we're trying to do is gather more of a suite of practices that will be possible to work in any community.”

For Market to Market, I’m Paul Yeager


Tags: buffer strips cover crops Des Moines Water Works DNR Elliott Griswold Iowa Department of Natural Resources nitrates pollutants pollution Remsen runoff water water treatment plants wells


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