USGS Identifies 42 Iowa watersheds on short list of 'Dead Zone' Polluting Watersheds
Iowa Legislature Must Stop Ignoring Impacts of Poor Manure Management
IOWA, April 2, 2009-For the first time, the U.S. Geological Survey has identified the top 150 polluting watersheds in the Mississippi River Basin that cause the annual 8,000 square-mile "Dead Zone" in the Gulf of Mexico. Many of these top polluting watersheds are in Iowa.
Marine dead zones can be caused by too many nutrients (nitrogen and phosphorus) in the water. Excess nutrients cause excess algae growth which, in turn, causes oxygen levels to drop too low to support marine life.
The USGS announcement on Wednesday identified 42 Iowa watersheds to be among the top 150 watersheds contributing too much nitrogen and/or phosphorus to the Gulf of Mexico and the resulting Dead Zone.
This is not the first time that Iowa nutrient problems in Iowa waters have been linked to problems downstream. In January of 2008, USGS identified 9* states, including Iowa, as the source of over 70 percent of the Gulf Dead Zone pollution. Nitrogen and phosphorus pollution from commercial fertilizers and animal manure from farmland were the biggest contributing sources in these states.
"It is ironic that our legislature is currently considering a bill that would weaken new rules proposed by the Iowa DNR to reduce runoff of manure applied to frozen or snow covered cropland during the winter," said Marian Riggs Gelb, executive director for the Iowa Environmental Council.
Riggs Gelb is asking legislators to vote no on House File 790 (Manure on Frozen Ground bill) and to let the Iowa Department of Natural Resources do their job to establish strong rules to protect water quality in our rivers and streams by limiting winter applications of both liquid and solid manure.
The Iowa Environmental Council is urging state policy makers to use the USGS list to prioritize and better direct watershed improvement programs.
Susan Heathcote, water program director for the Iowa Environmental Council also wants legislators to continue to support funding of state programs, such as the Watershed Improvement Review Board grants program, and to do so in a way that targets funding to high priority watersheds.
Targeting of federal funding to high priority watersheds is important, too, says Heathcote.
"While state funds are a part of the solution, the Environmental Protection Agency and the USDA need to take the lead to target additional federal watershed grants and farm conservation programs to help reduce the Dead Zone, which is a major national priority," said Heathcote.
Heathcote emphasized that conservation work done in the top 42 polluting Iowa watersheds contributing to the Gulf Dead Zone, is also work that benefits Iowa.
"The Cedar, Iowa and Des Moines Rivers are just a few of our important waters on this USGS list and all are very important water resources for our state. For example, sections of the Des Moines River are listed as impaired by the state because of high nitrogen loading affecting the drinking water for the City of Des Moines," said Heathcote.
*The 9 states contributing over 70 percent of the dead zone-causing nitrogen and phosphorus pollutants are: Illinois, Iowa, Indiana, Missouri, Arkansas, Kentucky, Tennessee, Ohio, and Mississippi.