Des Moines, Iowa, City Council is poised to file a federal lawsuit against several watershed councils in order that the level of nitrates be reduced in city drinking water. (Click here or above to see the news article) Even though Iowa is one of only two states in the Mississippi River Basin to have a nutrient reduction plan in effect, the effort has not diminished the nitrate levels in the Raccoon River flowing through downtown Des Moines. The river is a source of drinking water for the city.
There are a couple of ways to reduce runoff. One is mechanical, the other is vegetative. Installing monitoring stations at the edge of fields does a good job telling regulators how much nutrient is leaving. The cost to install even low-cost equipment gets expensive if you’re required to install hundreds on a farm of a couple thousand acres. And, monitoring the field, while useful, doesn’t reduce runoff.
The Environmental Protection Agency is among the regulatory agencies stepping up pressure on farmers to cut runoff of nitrates, coming from animal waste and fertilizers. The EPA says that other measures are effective of reducing or eliminating that runoff…cover crops are among the least expensive. Here are their suggestions:
- Cover crops: Planting certain grasses, grains or clovers can help keep nutrients out of the water by recycling excess nitrogen and reducing soil erosion.
- Buffers: Planting trees, shrubs and grass around fields, especially those that border water bodies, can help by absorbing or filtering out nutrients before they reach a water body.
- Conservation tillage: Reducing how often fields are tilled reduces erosion and soil compaction, builds soil organic matter, and reduces runoff.
Don Wirth, a grass seed grower from Oregon, has been working with corn and soybean farmers in the Midwest for more than a decade. He said that it’s sad that the farming industry could not accomplish the task of reducing runoff without government intervention. He is optimistic, however, that the popularity of cover crops will constitute an effective and less expensive method of reducing nutrient runoff.