Addressing Urban Flooding

The need to address urban flooding in Chicago cannot be overstated. Flooding disrupts lives, damages property, creates favorable environments for mold growth, and exposes residents to floodwaters mixed with sewage and industrial contaminants.

As global temperatures continue to rise, Chicago (like other cities) is experiencing changes in weather patterns like increased frequency and intensity of rainfall events. The city’s bedrock layer restricts the absorption of rainwater into the ground, and concrete and asphalt that cover large areas of the city create vast impermeable surfaces. When rainwater falls, it runs off the surface and either collects in low-lying areas or quickly drains into the combined systems. The rate at which rain falls can overwhelm certain areas of Chicago. Specifically, South and West Side neighborhoods and near west suburbs of Chicago are hit the hardest.

WHAT SHOULD POLICYMAKERS DO?

We can take short and long term steps to lessen the negative impacts of flooding and reduce the scale of combined sewer overflow.

Alert System For Household Water Use

The most urgent solution is to implement an alert system for mobile phones. When excessive rainfall becomes apparent, the alert system would disseminate a message to everyone in the impacted area, instructing them to reduce water usage at home. This city alert system could draw
inspiration from the Metropolitan Water Reclamation District (MWRD) and Friends of the Chicago River Overflow Action Days program, which is designed to let residents know when to halt water usage. Unlike Overflow Action Days, where individuals are required to sign up to receive emails, the city alert would flash notifications on phones in an impacted area similar to the Emergency Alerts system.

Due to the combined sewer system, when high volumes of rain enter the storm drains, households must hold their water. Too few people are aware that they should refrain from running dishwashers, doing laundry, or taking showers during rainy periods. An alert system, complemented by billboards and public service announcements, could guide people to reduce water consumption and possibly encourage them to participate in storm drain cleaning efforts.

Green Infrastructure

Flooding caused by saturation and impermeable surfaces can be addressed through implementation of green infrastructure. In September 2023, the Biden Administration announced $1 billion in funding for tree planting in areas most impacted by climate change. Chicago’s most flooded neighborhoods should be positioned to receive this money.

Green infrastructure encompasses various forms: trees and deep rooted plants, bioswales, rain gardens, design of structures that retain and support the flow of water, and permeable pavement and lots. In Chicago, it is crucial to create curbside wetlands in areas where water tends to accumulate during rain events. These wetlands would feature water-absorbing, filtering plants that are installed on parkways and curbs.

The development and implementation of green infrastructure can be tied to a green economy, educational initiatives, and community outreach programs in areas most affected by flooding. Young people still in school can participate in summer programs, while year-round programs can support employment and business development available to people of all ages. This approach allows for the local management of green infrastructure design, communication, and maintenance. Building local knowledge reduces the need for outsourcing services while simultaneously enhancing community resilience and climate adaptation.

Bolster Infrastructure In Vulnerable Areas

Prioritize infrastructure improvements in flood-vulnerable areas, with a particular focus on the South and West Sides. As MWRD works to increase the capacity of the Deep Tunnel storage system, smaller green and gray infrastructure systems can mitigate the impacts of rain events.

When planning such infrastructure, flood-vulnerable communities should be at the forefront. To achieve this, it is essential to actively engage residents in decision-making processes. This is necessary to ensure the unique needs and concerns of each community are considered.

Portable Water Recycling Units

In addition to green infrastructure measures, the City of Chicago should consider portable water recycling units that can be installed during rain events to filter and store rainwater. This initiative can eliminate hazardous contaminants and serve as irrigation water during periods of drought. It
is likewise urgent to install local reservoirs beneath parks and parking lots in neighborhoods that experience recurrent flooding. These reservoirs can capture and hold a significant volume of water, preventing the stormwater drainage system from becoming overwhelmed.

Transform Lakefront Into Reconstructed Wetlands

Flooding due to high lake levels can be mitigated by transforming the hard edges of the lakefront into reconstructed wetlands. Federal funding, such as from the Great Lakes Restoration Initiative, can support this. In tandem, it is vital to cap the lakefront Chicago Area Confined Disposal Facility and implement onsite state-of-the-art green remediation.