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

Unchecked climate change threatens the Quad Cities’ economic viability, natural assets, and public health; our assessment describes the challenges and a range of solutions.

As climate change intensifies, extreme weather – including flooding, droughts, and high temperatures – will affect the quality of life in the Quad Cities of Iowa and Illinois. This assessment from the National Wildlife Federation, Prairie Rivers Network, and the University of Illinois’ Discovery Partners Institute developed localized climate models to analyze what could happen under a variety of emissions scenarios. The goal is to provide Quad Cities residents with a better understanding of what climate change might bring and to outline some options for creating a healthier and more resilient future.

Overall, the intensity and frequency of flooding, drought, and extreme heat are projected to increase in the Quad Cities over the 21^st century. Key findings from the assessment's climate projections include:

Rock Island and other downstream areas will face the highest flood risks, as higher floods fueled by warmer temperatures could overtop existing levees already at risk of failure.
Davenport and Bettendorf are expected to experience multiple flood events under a high-emission scenario, in part due to the relatively high levels of impervious cover.
Climate-fueled flooding and extreme heat may have disproportionate impacts on the socially vulnerable populations of East Moline, Rock Island, and Davenport.
Critical infrastructure that connects the region, like the I-74 bridge, will become more prone to flooding.
Several areas including Cargill AgHorizons, Isle Casino Hotel Bettendorf, portions of Rock Island Arsenal Island, Martin Luther King Center, Vibrant Arena at the MARK, Lindsay Park Yacht Club, could become susceptible to flooding as soon as 2040.
The Quad Cities currently experience an average of three days over 95 degrees a year. That could increase to roughly 28 days by the end of the century in a lower-emission scenario and to 58 days a year in a higher-emission scenario. Extended high temperatures increase the risk of asthma, heart attacks, and heatstroke.
Trees in the Quad Cities currently absorb approximately 69 million gallons of storm runoff, 3 million pounds of air pollution, and more than 100,000 tons of carbon pollution annually. However, increased heat, flooding, and droughts all threaten the health and survival of the Quad Cities’ urban forest.
Nahant Marsh currently catches and filters up to two billion gallons of water during severe rain events. The stressors of climate change could decrease its ability to capture and filter floodwaters, which could increase flood heights in the Quad Cities.

The impacts of climate change will be felt by everyone in the Quad Cities region. Vulnerable groups, including those with lower socioeconomic status, Black, Indigenous, People of Color communities, renters, people experiencing homelessness, immigrants, and people with disabilities will be more likely to experience significant health impacts from heat or catastrophic property losses from flooding.

The assessment includes several recommendations for enhancing the region's resilience in the face of climate change:

The modeling results found that solutions such as green roofs, permeable pavement, and stormwater swales could significantly mitigate flooding caused by urban runoff.
To mitigate flooding from the Mississippi River itself, larger-scale solutions are necessary. The 382-acre Nahant Marsh is an example of how a restored wetland ecosystem can affect flood heights at a regional scale.
Increasing green spaces in vacant lots, restoring ravines, and increasing equitable river access are some ways community leaders are actively thinking about ecosystem restoration in the Quad Cities.

A number of Quad Cities stakeholders helped shape this assessment, better aligning the nature-based solutions considered with community concerns and knowledge. These findings are meant to be a starting point for resilience conversations within the Quad Cities communities. The local stakeholders who reviewed this assessment noted that more education, research, and funding will be necessary to identify and implement specific solutions, and ultimately make the region more resilient to the impacts of climate change. We plan to broadly disseminate these findings to build local support for community-selected resilience solutions, with a focus on the region’s more vulnerable communities.