Did you know that Des Moines Water Works has owned about 100 acres of farm land at Maffitt Reservoir Park since 1942? In keeping with DMWW’s mission, and knowing that what we do on the land impacts the quality of our source water, we seek to adopt agricultural practices that provide protection to the water and soil resources under our ownership.
This fall, a cover crop was planted on DMWW’s Maffitt farm land. The cover crop was applied using a helicopter that planted seed in a standing soybean field. A mixture of rye (cool season grass/grain non-legumes) and hairy vetch (cool season annual legume) were planted.
Cover crops have been around for centuries, but are gaining in popularity because of their ability to control erosion, improve soil water moisture content, and the natural filtration of water through the soil profile. When the cover crop decays, it provides organic matter to produce beneficial soil organisms for soil fertility and soil health. Healthy soils improve the infiltration of water, leading to less flooding as well as reduced soil erosion and nutrient (nitrogen and phosphorus) leaching. According to an Ohio State University Extension report, Using Cover Crops to Improve Soil and Water Quality (2009), a pound of soil organic matter has the ability to absorb 18–20 pounds of water, reduces nutrient and pesticide runoff by 50% or more, decreases soil erosion by 90%, reduces sediment loading by 75%, and reduces pathogen loading by 60%.
By using cover crops and reducing reliance on agrichemicals for crop production, we help protect the health of family and friends and reduce water quality concerns arising from non-point pollution attributed to farming practices. At a time when the Raccoon and Des Moines River watersheds suffer from serious degradation due to nutrient contamination, this shift in agricultural systems can play a significant and positive role in revitalizing Iowa’s river systems. For more information about cover crops, visit Practical Farmers of Iowa at http://www.practicalfarmers.org/programs/Field-Crops_cover.php or Midwest Cover Crops Council at http://www.mccc.msu.edu/.