The Chicago Region: Coordinating Flood Resilience in a Dense Urban Landscape

Background

Home to over 8.4 million people across seven counties and more than 284 municipalities, the Chicago region faces significant urban planning challenges, particularly related to stormwater and flood management. Due to its geography—broad floodplains and clay soils—combined with dense development and aging infrastructure, the area is increasingly prone to urban flooding. Key organizations like the Chicago Metropolitan Agency for Planning (CMAP) and the Illinois Department of Natural Resources (IDNR) have worked to implement planning policies that address flooding while improving environmental and community resilience.

The Problem

The rapid urbanization and sprawl across the Chicago metropolitan area have led to increased impervious surfaces and strain on outdated sewer systems. These conditions, worsened by climate change, have made urban flooding a frequent and costly issue, impacting both public and private property and endangering lives.

The Strategy

Efforts to mitigate flood risk began with the 1996 model floodplain ordinance, created by the Northeastern Illinois Planning Commission (NIPC), which laid the groundwork for floodplain protection and National Flood Insurance Program compliance.

This was followed in 2003 by the Conservation Design Resource Manual, which provided municipalities with tools to revise zoning and subdivision ordinances to include open space preservation, reduced impervious surfaces, and improved stormwater management.

In 2015, under the Urban Flooding Awareness Act, IDNR conducted a statewide assessment of urban flooding, identifying major sources of damage and recommending both structural and nonstructural solutions, including homeowner education, tailored community-level strategies, and integrated green-gray infrastructure planning.

Lessons Learned

The Chicago region demonstrates how large, fragmented metropolitan areas can make meaningful progress on flood resilience through coordinated planning, policy tools, and ongoing evaluation. While flooding has continued to worsen due to increasing development and climate stressors, efforts such as model ordinances, conservation design practices, and comprehensive planning have laid a strong foundation for long-term mitigation.

No single approach can solve urban flooding alone. Collaboration across jurisdictions and consistent support from regional organizations like CMAP and IDNR are vital to translating technical knowledge into effective, localized action.