Press Release

New Report Analyzes Expansion of CAFOs in Iowa’s Floodplains

Geospatial analysis confirms illegal expansion in locations across the state

DES MOINES — This week the Iowa Environmental Council (IEC) and Environmental Law & Policy Center (ELPC) published “Animal Feeding Operations in Iowa’s Floodplain: A Risk to Iowa’s Waters,” a report that details animal feeding operation (AFO) construction and expansion in Iowa’s 100-year floodplain. The Environmental Working Group performed geospatial analysis on AFOs in Iowa’s floodplains.


Since 2002, Iowa law has prohibited new and expanded confined AFOs on the 100-year floodplain. The legislature charged the Department of Natural Resources (DNR) with developing a floodplain map to identify the areas to apply the construction restrictions. However, since that directive, DNR has not developed or adopted the floodplain map more than 20 years later.

“Iowa law recognizes that animal feeding operations are unsafe in a floodplain where floodwaters can carry pollutants into rivers that provide Iowans with drinking water and recreational opportunities,” said Josh Mandelbaum, Senior Attorney at ELPC. “We have been waiting for decades for DNR to adopt a floodplain map to implement the law. This report illustrates the consequences of failing to comply with the law. We cannot afford for the state to wait any longer.”

Iowa has seen both extreme and long-term flooding throughout the state since 2002. When a manure storage structure floods, it can pollute waterways with pathogens, nitrogen, and phosphorus. In the twenty years since the floodplain exclusion law passed, the DNR has been operating under a case-by-case approach to site review. The analysis found that DNR’s interim process has not done an adequate job of preventing AFO construction and expansion in the 100-year floodplain.

“EWG found 117 animal feeding operations in and near Iowa’s floodplains – close to half of which have expanded in recent years,” said Al Rabine, geographic information systems analyst with EWG. “These facilities are at a higher risk of flooding, especially given the intensifying climate crisis, and they pose a clear and present danger to the environment and public health.”

In the report, IEC and ELPC call on DNR to follow state law and adopt an official 100-year floodplain map as part of the the department’s current rulemaking process, while also urging state leaders to consider whether the current law is protective enough. The groups have previously petitioned the DNR on the issue, and the petition remains under DNR review.

“Open feedlots are exempt from the 100-year floodplain exclusion rule, and in proposed rule changes, DNR removes the provision that says small AFOs are prohibited,” explained Michael Schmidt, Staff Attorney for IEC. “Small AFOs and open feedlots generate the same risks to clean water in our floodplains and should also be explicitly prevented from siting in the 100-year floodplain.”

The outcome of climate change increasing precipitation and flooding in Iowa also plays a major factor in considering the efficacy of the two-decade old flaw.

“As our state faces new environmental challenges due to climate change, it is time to reevaluate whether old regulations are protective enough,” said Alicia Vasto, Water Program Director for IEC. “As 100-year and 500-year flood events become more frequent, state leadership must ensure clean water protections are keeping pace.”

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