Central Iowa Water Report yields public outcry - and EPA answers by delisting polluted rivers

On July 1, 2025, the Harkin Institute and Polk County released the findings from the Central Iowa Source Water Resource Assessment (CISWRA) report titled Currents of Change. A month later, more than 1000 people gathered in Des Moines to hear the first presentation on the report.  The experts agree: Iowa’s waterways are impacted by agricultural pollution. You can read the entire report or view the executive summary to learn more. For additional highlights and takeaways, watch the full presentation and listen to episodes 3 and 4 of the Canary in a Cornfield podcast.

Story and video from Iowa Environmental Council   

LWV UMRR Chair, Mary Ellen Miller: IS THIS THE TIPPING POINT?
Water is almost always the environmental news story in Iowa.  Today, the topic of Iowa's water quality is frequently combined with concerns about the impact on our public health.  In addition to the erosion of our precious top soils and the flow of the excess nitrogen and phosphorus down the Mississippi River that creates the Gulf of Mexico "dead zone," Iowa now needs to also deal with having the second highest and the fastest growing cancer rate in the nation.  A simple graphic noting the location of every CAFO in Iowa so closely resembles the graphic that notes the areas with the highest cancer incidences that one cannot help but ask the question: might there just be a correlation between the two?  

And it is not just cancer; scientists are also concerned about the increasing incidence of Parkinson's, birth defects, and fertility issues.  This summer, the Iowa DNR weekly lists the state park beaches that are closed to all recreational uses due to high rates of e coli and microcystins in the waters; it is usually between 12 and 18 beaches that are closed. Entering these contaminated waters is dangerously toxic to children and small animals; yet many never hear of these notices.  Why is that? 

We cannot escape the reality that change needs to happen to clean up Iowa's polluted waters.  Will the CISWRA report be the "tipping point" that wakes up our state leaders to acknowledge we cannot continue on this path of destruction of our natural environment?  Or will it be the public that wakes up and demands that funding for monitors in our rivers and streams continue and that Iowa ignores the delisting of our rivers as impaired and ramps up efforts to stop the pollution.  Is Iowa's water "crisis" at a point that we can agree that our "voluntary" nutrient reduction program is not working and regulation can finally be considered as part of the solution?  I certainly hope so. ​

---

And then, EPA removed Iowa rivers from impaired waters list* despite high nitrate levels.  The EPA is removing seven Iowa river segments, including water in the Des Moines and Raccoon rivers, from the impaired waters list.   Story coverage from WeAreIowa news (channel 5, Des Moines) is to the right.  

On July 11, 2025, EPA issued a letter to the Iowa Department of Natural Resources (DNR), rescinding its disapproval of the state's 2024 impaired waters list.  This unprecedented action means that major rivers in Iowa are not treated as exceeding the nitrate standard for purposes of the Clean Water Act despite having nitrate levels in the water greatly exceeding standards.

*What is the Impaired Waters List? 
Under the Clean Water Act, every state must adopt water quality standards that define how it would like to use its waters and the pollution levels that would prevent those uses. When a water does not meet the standards and is too dirty for one of its intended uses, it is “impaired.” Section 303(d) of the Clean Water Act requires states to submit a list to EPA once every two years identifying impaired waters that need a plan to reduce pollution. EPA must approve or disapprove the list. Iowa DNR submitted its list in 2024 with 705 impairments. 

States must develop a water improvement plan for each waterbody on the impaired waters list and submit them for EPA approval. The plans must identify sources of pollution and the amount of pollution reduction needed to meet the water quality standard and protect the designated uses. The reductions are incorporated into permits for point sources, such as wastewater treatment facilities, but are not required for nonpoint sources, such as agriculture.