URBANDALE, Iowa - The Iowa River has received a lot of attention in the last couple months, being recently named by American Rivers as one of “America’s ten most endangered rivers,” and appearing on the State of Iowa’s 303d list for bacteria and pathogens.

American Rivers is a national organization of more than 65,000 members and supporters who protect and promote rivers as assets that are vital to national health, safety and quality of life. Under Section 303(d) of the Federal Clean Water Act, states are required to submit a list of waters where water quality is not sufficient to meet all state water quality standards.

The primary impairment cited by both American Rivers and the State of Iowa is the presence of E. coli and other indicator bacteria in the river. Nutrient issues are also cited as a concern because of the intensive crop and livestock farming throughout most of the watershed.

E. coli is a bacteria found in the digestive systems of animals. Generally, they aren’t thought to survive for long outside the gut. Many are killed in a dry soil environment. However, survival studies show that they have a half-life of a week to ten days. Some scientists suspect that E. coli can settle in stream sediments and survive — even reproduce or become reactivated under the right conditions. Genetic studies are needed to confirm the theory.

A random thimble of Iowa soil would contain literally billions of bacteria, with E. coli being just a tiny, tiny fraction of that. When E. coli moves, it has to run along the surface of the ground in water; it generally doesn’t work its way through soils, unless it’s very sandy or cracked soil.

National Soil Tilth Laboratory (NSTL) Scientist Tom Moorman has been actively researching issues surrounding the impact of agriculture on the environment in the Iowa River basin, with several ongoing projects underway in South Fork, a tributary of the Iowa River that runs through southern Hardin County.

Moorman says that the presence of E. coli in the river is a concern, but that it is also a very complex issue. “We find some E. coli everywhere. For example, in one research project we monitored two fields — one with a history of manure application and one with no known history of manure application. When we monitored and analyzed the runoff, we saw significant amounts of E. coli coming from both fields. More came from the manured field, but the amount of E. coli that came from the non-manured field was substantial. That research indicates clearly that livestock manure coming off farm fields is not the only source of E. coli.”

“We also know that, at the watershed level, other sources exist, including wildlife and inadequate septic and municipal sewage systems. When you combine the knowns and unknowns, it becomes very difficult to assign sources of E. coli contaminants in stream waters.”

Moorman and other scientists know that livestock can play a significant role in contributing E. coli to the Iowa River. He says that the management of livestock and their manure is critical. “Obviously, giving cattle free access to streams contributes to fecal contamination. In fact, we think that a small number of animals in close contact with a stream could have a larger impact than greater numbers that are kept away from streams and have their manure managed properly.”

At the end of the day, there are many unknowns surrounding the issues of pathogens and bacteria in the Iowa River. Moorman says that although data collection methods improve all the time, very little historical data exists. “It doesn’t mean E. coli wasn’t there in the past, it’s just that we can detect it and measure it now. And the known impacts of E. coli are limited to human impacts — they make people sick.”

“When it comes to pathogens like E. coli in the Iowa River, we’re mostly trying to just understand the dynamics of the problem and apply research to it. Once we’ve done that, then we can come up with some workable recommendations. But eliminating manure isn’t probably going to be an option — we know definitively that manure is good for soil, and that E. coli don’t harm soil.”

Many farmers are recognizing that they need more information and alternatives to minimize effects of farming on water quality. In 1999, farmers in the South Fork watershed became concerned enough about water quality issues that they created the Southfork Watershed Alliance (www.southforkwatershed.org)

Since then, South Fork area farmers have been working on techniques to address water quality by building partnerships between the Southfork Watershed Alliance, Iowa Soybean Association, National Soil Tilth Laboratory, Validus, USGS, Hardin County Conservation Board, Farm Service Agency, ISU Extension and others.

Hubbard-area farmer Allen Kadolph says he has been involved in the Southfork Watershed Alliance since he heard there was an effort underway to get it started. “After attending the first informational meeting, I decided to get involved. We started from scratch, because there isn't as much information out there as we thought there should be.”

“What we've learned is that each watershed is a unique, complex system. You can't assume anything — everything has to be proven with on-the-ground research. We assumed we could just look up which farming practices would do the most good here and apply them, but there isn't much information to go on, and what we found says to go work on the ground and develop your own data. So we found ways to work with a number of partners to do our own research.”

One of the principal activities is guided stalk sampling. Samples of corn stalks are evaluated for nitrogen levels, which can reveal how much nitrogen the corn crop had available to it at critical, crop-producing times.

Too little nitrogen indicates that the farmer is losing yield and suffering economically. Too much nitrogen, and the farmer is overspending on crop nutrients. The economic “sweet spot” is the “optimal” category. And when the crop is at “optimal,” it means that it's using nutrients at the most efficient levels possible, where it is assumed there are environmental benefits as well.

The goal is to gather data on the use of nitrogen in corn production, so that farmers can improve economic and environmental performance by applying as close to the right amount of fertilizer as possible. The process is called “management evaluation.” Along with dozens of other area farmers, Kadolph is realizing the benefits of the process across the entire farmstead, as they apply the techniques to other management questions.

“We've studied several issues,” says Kadolph. “Now, we plant no-till soybeans into cornstalks, we've changed our crop rotation, and I definitely watch residue management more closely. We can see some impact from the management of micro-areas on our farm.”

National Soil Tilth Laboratory (NSTL) Soil Scientist / Hydrologist Mark Tomer has been working with farmers on issues of nutrient management. “On-farm evaluation of nutrient management is exactly what growers need to make their farming operations as efficient as they can be,” says Tomer. “A review of nutrient management in context with a group of neighboring farming operations allows us to understand how a group of farmers is doing with nutrient management. But every farm operation is different, and every grower approaches the idea of making changes in farm operations from a unique and individual perspective. Most of all, farmers need the opportunity to evaluate the efficiency of nutrient use for their own operation. When it comes to agriculture, improvements in environmental and economic outcomes go hand in hand. That's the best step we can take toward addressing environmental concerns. ”

Leah Maas is a fifth-generation farmer in the area who is President of the Southfork Watershed Alliance. “We have seen so much publicity about agriculture and how crop nutrients and manure are flowing down our streams and rivers. That's simply not the case. But over the last three years, the Iowa Soybean Association has sponsored fall nitrate corn stalk sampling, giving us a snapshot of how well the nutrients served the crop that particular year.”

“The work takes into account variables like soil type, tillage practices, form of nutrient, and timing of application. At the end of the season, these variables are all analyzed and charted anonymously so farmers can compare not only their own field, but also others in the area. Having the data to look at is going to help farmers document what they're doing and improve their environmental management.”

Dave Sweeney of Sweeney Farms near Buckeye is former President of the Southfork Watershed Alliance. He says that the South Fork watershed has many specific challenges. “Our watershed is unique compared to many others across the country in that it is home to a large number of confinement feeding operations (primarily swine and poultry) providing abundant, soil applied, animal waste. Additionally, members of the Southfork Watershed Alliance realize that the abundant rainfall and water holding capacity of our area is a great natural resource. We have a responsibility to insure that the overall environmental quality of the watershed is intact for generations to come.”

“So we've assembled a balanced group of farmers, agribusiness, concerned citizens; and NRCS, NSTL and Extension staff. For several years now, we've been bringing in programming that has been helpful for producers in evaluating their operations for environmental performance. It's our hope that we'll be able to document our progress in time. It's the goal of the Southfork Watershed Alliance to show by example that viable, economically and environmentally stable operations can exist here and to mentor the rest of the watershed.”

Efforts like these may seem small in the beginning, but they demonstrate momentum toward larger efforts and true impact on the watershed. But over three years, the Iowa Soybean Association, the Southfork Watershed Alliance, and local farmers have collected over 1,200 guided fall corn stalk samples to help them fine tune their nitrogen management. In addition, 30 South Fork farmers have participated in nutrient, soil, and pest management planning on 100 fields through a program called CEMSA (Certified Environmental Management Systems for Agriculture).

And the South Fork of the Iowa River is just one place that farmers are fine-tuning farming practices using Iowa Soybean Association programs like the On-Farm Network, CEMSA and Watershed Programming to evaluate and improve environmental performance. To learn more, go to www.isafarmnet.com/ep/