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Member Research & Reports

Member Research & Reports

Iowa Researchers Fault State’s Water Pollution Strategies

Iowa’s growing problem of nutrient pollution in waterways is not being adequately addressed by current state policies which rely heavily on voluntary conservation practices, according to newly published research.


[Photo: Dr.  David Osterberg]

An Iowa Policy Project (IPP) report co-authored by University of Iowa professor of occupational and environmental health Mr. David Osterberg and UI graduate student Mr. Aaron Kline finds that shortcomings in Iowa’s Nutrient Reduction Strategy (NRS) result in impaired rivers and lakes throughout the state and contribute to other downstream environmental problems, including a large ‘dead zone’ in the Gulf of Mexico.

Iowa’s NRS, which sets a goal of 45 percent reduction in nitrogen and phosphorus pollution, employs different strategies for so-called ‘point’ (e.g., cities’ waste treatment and industry) and ‘non-point’ (mainly farms) pollution sources. There are mandated nutrient reductions for some municipal waste treatment plants and industries, however, only voluntary measures are required for agriculture, which produces a majority of nutrient pollution, according to IPP. There is no target date to achieve the reduced pollution goals.

“The Nutrient Reduction Strategy is a blunt tool that takes different approaches to urban and rural runoff, and is especially weak on the larger, rural source of pollution from applied nutrients,” said Dr. Osterberg. “Given recent trends and documented attitudes, it is clear we need a stronger approach if Iowa is to seriously counter nitrogen and phosphorus pollution in our streams and lakes.”

The IPP report, available at, cites ongoing threats to Iowa water quality, including impaired or potentially impaired ratings in 2012 for over three-fourths of Iowa streams and rivers and about two-thirds of lakes and reservoirs.

The report recommends several policy changes for Iowa to reach its water quality goals:

• Giving focused attention to the problem, especially important to a voluntary-oriented approach.

• Assuring sufficient funding from the state for water quality.

• Adopting nutrient criteria standards for all Iowa waters, following federal Environmental Protection Agency guidelines.

• Initiating water-quality monitoring to determine whether the 45 percent goal is being met.

• Requiring all farms statewide to implement at least two conservation practices.

• Stipulating that additional regulation will follow if a voluntary strategy does not work.

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