The Mississippi River flows through Illinois, Iowa, and Wisconsin, carrying vast quantities of nutrient-rich freshwater and sediment to the Gulf of Mexico. Agricultural and urban runoff, primarily from fertilizers, animal manure and wastewater discharges, increase nitrogen and phosphorus in the river, resulting in hypoxia zones. These so-called dead zones possess dangerously low oxygen levels, which deplete valuable fisheries and harm the marine ecosystem.

To address this, the U.S. Environmental Protection Agency (EPA) established the Mississippi River/Gulf of Mexico Hypoxia Task Force in 1997 to develop a national strategy to reduce, limit and control hypoxia in the Gulf of Mexico. Over the years, the task force has updated its strategies, including the 2008 Gulf Hypoxia Action Plan and subsequent progress reports, to refine approaches for reducing nutrient pollution and improving water quality outcomes. Iowa, Wisconsin and several other states have been part of this task force, working to implement region-specific solutions 

How Iowa and Wisconsin Nutrient Reduction Strategy improves water quality

 Let's look at how implementing Iowa and Wisconsin's Nutrient Reduction Strategy helps improve water quality.

 Iowa Nutrient Reduction Strategy​

The Iowa Nutrient Reduction Strategy was developed by the Iowa Department of Agriculture and Land Stewardship, the Iowa Department of Natural Resources and Iowa State University to address nutrient loss in surface water. Here are some of the strategy's key points:

• Outlining voluntary efforts to reduce nutrients from point and nonpoint sources in a scientific and cost-effective manner.

Setting a goal to reduce annual nitrogen and phosphorus loss by 45%.

• Minimizing nutrient loss from nonpoint sources by encouraging voluntary adoption of agricultural conservation practices that prevent nutrients from leaving farm fields and entering nearby water bodies.

• Recommending point-source reductions by having selected municipalities and industrial facilities evaluate their nutrient control measures and assess the feasibility of upgrading nutrient treatment capacity. 

How Iowa Nutrient Reduction Strategy helps improve water quality

In May 2023, the updated Iowa Nutrient Reduction Strategy dashboards indicated measurable water quality progress. Some highlights from the updated reports include: An increase in covered crops planted in the state (from 10,000 acres in 2011 to more than 2.8 million acres in 2021). Cover crops are critical in reducing nitrate leaching and phosphate runoff. A rise in the number of farmlands protected by edge-of-field practices. Edge-of-field practices are agricultural techniques implemented at the edge of farmlands to slow, filter and process surface and subsurface runoffs. The cumulative number of acres protected by these practices, including saturated buffers and bioreactors, is 194 times higher in 2021 than in 2011. A rise in the number of point-source facilities meeting nitrogen and phosphorus load reduction targets. The number of point-source facilities meeting nitrogen load reduction targets increased from 10 facilities in 2015 to 47 facilities in 2021. The number of point-source facilities meeting their phosphorus load reduction targets increased from three facilities in 2015 to 23 facilities in 2021.

Source: Iowa Department of Agriculture & Land Stewardship

 Wisconsin Nutrient Reduction Strategy

The strategy was finalized in 2013 through Department of Natural Resources (DNR) leadership in partnership with the University of Wisconsin, federal, state and local conservation agencies, and others. Since its inception, the strategy has undergone periodic updates, including from 2015 to 2016 and during the 2017-2019 progress report, which highlighted phosphorus reduction successes and ongoing challenges in addressing nonpoint source pollution. The strategy's key points include:

• Setting a national goal to reduce nitrogen and phosphorus loading to the Mississippi River by 45%, helping shrink the hypoxic zone in the Gulf of Mexico.

• Addressing intrastate water quality needs for Wisconsin's lakes, streams and groundwater.

• Recognizing variations in nutrient contributions vary by river basin. In the Mississippi River basin, 80% of nonpoint phosphorous pollution comes from 20 of the 30 major river basins. In the Lake Michigan Basin, 80% of nonpoint phosphorous pollution comes from nine of the 13 major river basins.

• Maintaining regulatory framework by building on programs and requirements rather than introducing regulations for point or nonpoint sources.

How the Wisconsin Nutrient Reduction Strategy helps improve water quality

In April 2020, the implementation progress report of Wisconsin’s Nutrient Reduction Strategy for 2017-2019 was released. Some of the highlights of the report include: Reducing the amount of phosphorus in waterways. Past implementation efforts have reduced phosphorus from Wisconsin watersheds to the Mississippi River by 23% and to Lake Michigan by 27%. Reducing phosphorus loads from point sources. Point source phosphorus discharges are limited under the Wisconsin Pollutant Discharge Elimination System (WPDES) permit issued to municipal and industrial facilities. As a result, a 70% phosphorus load reduction has been realized between 1995 and 2018. Though the permit does not include a water quality criterion for nitrogen, it contains a requirement for quarterly effluent monitoring for total nitrogen. Nutrient reduction through agricultural nonpoint source programs. A Nutrient Management Plan (NMP) matches nutrient inputs (organic manures and fertilizers) to crop demand and is a holistic approach to nutrient flows and losses. In 2018, 8,220 NMPs were developed on 3.3 million acres, covering 36.6% of the state’s 9 million cropland acres.

Source: Wisconsin’s Nutrient Reduction Strategy Progress Report 2017 - 2019

Implementing these strategies requires partnering with an expert who can help optimize nutrient reduction measures.

How Fehr Graham can help communities in Iowa and Wisconsin develop Nutrient Reduction Strategies​

At Fehr Graham, we help communities across the Midwest develop cost-effective solutions for nutrient reduction and implement Nutrient Assessment Reduction Plans (NARPs). We also help secure funding for strategy implementation and stakeholder engagement. Our expertise in nutrient management and water quality solutions has helped improve water quality across several neighborhoods in Iowa and Wisconsin.

Karoline Qasem, PhD, PE, PMP, is a powerhouse in water resources engineering. She specializes in watershed, water quality, hydrodynamic modeling, regulatory permits, nutrient criteria development, watershed planning and stormwater management. Her groundbreaking research, particularly at the interface of environmental engineering and ecology, has revolutionized our understanding of urban streams. Reach her at This email address is being protected from spambots. You need JavaScript enabled to view it..