Chicago’s relationship with pollution control is shaped by its size, its history as an industrial powerhouse, and its position along Lake Michigan. As the third-largest city in the United States, Chicago has built a layered system of agencies, ordinances, and community-driven initiatives aimed at reducing pollution in the air, water, and land. The work is ongoing, and the methods continue to evolve as the city faces new challenges from climate change, e-commerce growth, and emerging industries such as data centers.
A Multi-Agency Framework
Pollution control in Chicago is not handled by a single agency. Instead, responsibility is distributed across city, county, state, and federal bodies that each play distinct roles.
At the city level, the Chicago Department of Environment (DOE) leads climate and environmental policy. The department was originally dissolved in the early 2010s, with its responsibilities absorbed by other city agencies. It was officially reestablished in 2023, and Mayor Brandon Johnson’s proposed 2026 city budget includes returning enforcement powers to the department, a move long sought by environmental advocates.
The Chicago Department of Public Health (CDPH) currently oversees environmental permitting and inspections. According to the department, its Environmental Permitting and Inspections team issues roughly 8,000 permits each year for activities that affect the environment, including the installation and operation of equipment with the potential to create or control air pollution, recycling facilities, waste handling sites, construction-related rock crushers, sandblasting, and chemical washing operations.
Cook County’s Department of Environment and Sustainability (DES) handles pollution control in suburban areas outside city limits, working in cooperation with the Illinois Environmental Protection Agency and the U.S. Environmental Protection Agency. The Metropolitan Water Reclamation District of Greater Chicago (MWRD) manages wastewater treatment and stormwater for much of the region.
Air Quality Efforts
Air pollution control is one of the most visible areas of regulation in Chicago. The city’s air quality is affected by traffic emissions, industrial activity, freight movement, and seasonal factors such as ozone formation during hot weather.
Chicago requires air pollution control permits for a wide range of regulated equipment, including combustion equipment, process equipment, and pollution control devices that have the potential to emit air contaminants. Inspectors visit permitted facilities to monitor compliance with conditions tied to those permits.
In recent years, Chicago has also expanded its focus on cumulative air pollution impacts. The Cumulative Impact Assessment, a citywide project, provides an inventory of pollution sources and identifies neighborhoods, primarily on the South and West Sides, that face the greatest combined environmental burdens. The Hazel M. Johnson Cumulative Impacts Ordinance, named after a pioneering Chicago environmental justice advocate, was passed in part to address these disparities.
Water Pollution and Lake Michigan
Lake Michigan supplies drinking water to most Chicago residents and serves as one of the city’s defining natural features. Protecting it from contamination is a central pillar of pollution control.
The Metropolitan Water Reclamation District operates a network of treatment plants that process wastewater before it is released into local waterways. The agency’s Tunnel and Reservoir Plan, commonly known as the Deep Tunnel, was built to reduce combined sewer overflows that historically allowed untreated sewage to reach the Chicago River and Lake Michigan during heavy storms.
The Chicago River itself has been the subject of decades-long cleanup efforts. Once heavily polluted by industrial discharge, the river is now home to a wider variety of fish species and supports recreational uses such as kayaking and boating. Disinfection of treated wastewater, which began in the mid-2010s, marked a major milestone in improving river water quality.
Waste Management and Recycling
Solid waste handling is another key piece of Chicago’s pollution control system. The city operates a Household Hazardous Waste Facility and hosts neighborhood collection events for items such as paints, batteries, electronics, and pesticides that should not be placed in regular trash.
In 2024, the city implemented a new ordinance requiring all recycling and waste-handling facilities to submit annual reports to CDPH documenting how waste and recyclables are handled, treated, and disposed of throughout the year. The requirement is intended to give regulators a clearer picture of how materials move through the city’s waste stream.
Chicago has also faced challenges with its blue cart recycling program, which has historically underperformed compared to other major U.S. cities. The Department of Streets and Sanitation has worked to expand outreach and improve education on what materials are accepted.
Environmental Justice
Pollution control in Chicago cannot be separated from environmental justice. South and West Side neighborhoods, which are predominantly Black and Latino, have historically borne the heaviest pollution burdens from heavy industry, freight corridors, and waste handling facilities.
The Chicago Environmental Justice Action Plan, developed by the Department of Environment in collaboration with eight other city departments, is the city’s first comprehensive roadmap for addressing cumulative environmental burdens. It outlines how city agencies will apply an environmental justice framework across policies, programs, and operations.
Chicago’s pollution control efforts continue to adapt. The growth of warehousing, data centers, and freight rail in recent years has raised new concerns about diesel emissions and energy consumption. Climate change is intensifying heat waves, storms, and flooding, all of which place added pressure on the city’s environmental infrastructure.
For Chicago, pollution control is not a single program but a sustained effort, shaped by regulation, community advocacy, and the daily work of inspectors, scientists, and city departments across the region.
