As climate change intensifies, extreme weather – including flooding, droughts, and high temperatures – will affect the quality of life in the Quad Cities, according to a new report. It also identifies options that could ease these impacts for residents.

“We found that the Quad Cities will begin to experience more frequent and more destructive floods shortly,” said Arsum Pathak, senior adaptation specialist for the National Wildlife Federation. “Our research also shows that solutions such as permeable pavement, green roofs, and stormwater gardens can significantly reduce flooding. It encourages the value of these local cost-effective measures while emphasizing the need for conserving and restoring natural features at a scale large enough to make a real difference.”

Download the report: Navigating Climate Challenges in the Quad Cities: A Comprehensive Assessment and Paths to Resilience

The assessment by the National Wildlife Federation, Prairie Rivers Network, and the Discovery Partners Institute at the University of Illinois System analyzed precipitation and flooding in the Quad Cities due to climate change at local scales through the end of the 21st century, considering additional elements such as rainfall intensity and frequency, existing drainage infrastructure, and the level of urbanization in each city. 

“Our analysis suggests the Mississippi region will experience warmer and wetter conditions in the future, along with an increase in extreme precipitation events,” said Ashish Sharma, the climate and urban sustainability lead at the Discovery Partners Institute. “The findings from the report will empower Quad Cities communities with scientific knowledge for accelerated investments and actions for municipal and regional planning as they deliberate flood mitigation options for creating a more sustainable and resilient future for the region.” 

Key findings from the report:

• Rock Island and other downstream areas are at particular risk, as higher floods could breach the existing levees. 
• Davenport and Bettendorf will likely experience repeated flooding in the coming decades, exacerbated by runoff from the densely developed landscape.
• Critical infrastructure such as the I-74 bridge, will be at an increased risk of flooding, threatening connectivity across the region.
• Places including Cargill AgHorizons, Isle Casino Hotel Bettendorf, the Martin Luther King Center, Vibrant Arena at the MARK, and Lindsay Park Yacht Club could become susceptible to flooding as early as 2040. 

Under a high-emission scenario, the Quad Cities could experience nearly two months of temperatures soaring above 95 degrees. The Quad Cities currently experience an average of three days over 95 degrees a year. 

“Extended summer heat waves could become the new normal in the Quad Cities,” said Nina Struss, river health and resiliency organizer for Prairie Rivers Network. “This kind of heat poses risks to vulnerable groups, including those with pre-existing health conditions and people working outdoors. The types of flooding solutions we modeled leverage the protective value of nature and can help reduce temperatures. Right now, we have a historic opportunity to secure funding for these initiatives through the Bipartisan Infrastructure Law and the Inflation Reduction Act.”
 
The assessment includes several recommendations for enhancing the region's resilience in the face of climate change: 

• The assessment demonstrated how solutions incorporating natural features – such as green roofs, permeable pavement, and stormwater gardens known as bioswales – could reduce flooding caused by runoff.
• Trees in the Quad Cities currently absorb approximately 69 million gallons of storm runoff, three million pounds of air pollution, and more than 100,000 tons of carbon pollution annually. Protecting the Quad Cities’ existing urban forest will reduce heat and flooding. 
• Community leaders are considering restoration projects such as converting vacant lots to green spaces, restoring ravines, and increasing equitable river access.
• To mitigate flooding from the Mississippi River itself, larger-scale solutions are necessary. For example, the 382-acre Nahant Marsh catches and filters up to two billion gallons of water during severe rain events. Ensuring that upstream wetlands like Nahant Marsh remain healthy in the future is one way to reduce climate-fueled flooding. A comprehensive solution for Mississippi River flooding will require coordinated action from stakeholders upstream.

The National Wildlife Federation and Prairie Rivers Network are committed to working with Quad Cities communities as they work to adapt to the challenges brought by a changing climate. 

“Our assessment doesn't have all the answers. The hope is that it will be a starting point for conversations about the options for creating a stronger and safer Quad Cities for all,” Struss said.