Metropolitan Water Reclamation District of Greater Chicago

Recovering Resources, Transforming Water

Strategic Plan

Protecting Our Water Environment

Established in 1889, the MWRD is an award-winning, special purpose government agency responsible for treating wastewater and managing stormwater in Cook County, Illinois. We strive to be a responsive neighbor that engages with the public on several critical water-related issues that improve the quality of life for all.

Stormwater Partnerships

Local governments and public agencies can apply for funding to build or design stormwater projects.

Strategic Plan

See our NEW 2026-20230 Strategic Plan Overview draft!

A crane lifting a large chemical storage tank into position at a water treatment facility with the Chicago skyline visible in the distant background

Procurement and Materials Management

The Procurement and Materials Management Department issues many contracts during the year to purchase a wide range of materials, services and equipment for the MWRD.

Overflow Action

You can help reduce basement backups and flooding by conserving water before, during and after rainstorms.

Tunnel and Reservoir Plan (TARP) Reservoir Levels

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The Metropolitan Water Reclamation District of Greater Chicago's Tunnel and Reservoir Plan (TARP) is designed to reduce flooding, improve water quality in Chicago area waterways and protect Lake Michigan from pollution caused by sewer overflows.

Street flooding and basement backups can still occur even when there is plenty of room in TARP. If small neighborhood sewers don’t have the capacity to carry water to the MWRD’s intercepting sewers or TARP tunnels, they may back up.

If TARP is full, neighborhood sewers are designed to overflow to waterways.

Learn more about the Tunnel and Reservoir Plan

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Join our team!

We are accepting applications now for a wide range of job categories.

Find out more

You can help prevent flooding and protect water quality!

Native Landscaping

Native landscaping can help reduce flooding, protect water quality and provide habitat for wildlife.

Rain Barrels

We have rain barrels for sale for a low price, delivery included. Rain barrels capture rainwater from your roof and save it for later use.

Green Infrastructure

Capturing stormwater where it falls through natural systems and permeable surfaces.

Medication Disposal

When not disposed of properly, pharmaceuticals can end up in waterways. You can help keep pharmaceuticals from entering our waterways by disposing of unwanted medicine properly at the locations listed on this page.

Videos

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Join Our Team

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Where Does IT Go?

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Virtual Tour

Recent News Releases

"MWRD targets odor concerns," Homewood-Flossmoor Chronicle

July 13, 2026

The Metropolitan Water Reclamation District of Greater Chicago (MWRD) expects to have two projects totaling $5 million to address odor mitigation near its Thornton Reservoir completed by the end of 2026, bringing total mitigation efforts over the past decade to $8.6 million, according to officials.

“Smelly south suburban reservoir will take at least a month to drain,” NBC 5 Chicago

July 11, 2026

The massive Thornton reservoir, a south suburban quarry holding billions of gallons of stormwater and sewage that nearly filled up this past week, will take at least a month before it drains. Thornton is part of the Deep Tunnel flood-control system and resembles a canyon in South Holland. It takes in sewer wastewater during heavy storms that is later pumped out to the Calumet treatment plant at East 130th Street in the Far Southeast Side Riverdale neighborhood. For the first time since opening in 2015, the quarry filled to near capacity along with another flood-control reservoir known as McCook in Bedford Park.

"Deep Tunnel reservoir will take at least a month to drain," Chicago Sun-Times

July 11, 2026

The nearly 8 billion-gallon Thornton reservoir, which helps prevent flooding, was nearly full this week. The sewer water is slowly being pumped out but it will be weeks before the south suburban quarry is dry again.

“MWRD Announces Projects to Remedy Stench of Thornton Reservoir,” WTTW

July 10, 2026

The Deep Tunnel system did its job this week, keeping billions of gallons of storm and wastewater from flooding people’s homes following a deluge of rain over the 4th of July holiday weekend. But a whole lot of that water continues to stew in the massive Thornton reservoir, which serves the South Side of Chicago and 13 south suburban municipalities.

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Projects

LeMoyne Street and Maypole Avenue Underground Storage Projects | MWRD

The MWRD and Chicago Department of Water Management are partnering on two projects on the West Side of Chicago to build underground storage tanks that can contain a combined 1.7 million gallons of stormwater to mitigate local flooding.

Harvey Central Park Stormwater Detention Basin | MWRD

The MWRD's Harvey Central Park Stormwater Detention Basin project will provide flood relief for the city of Harvey. This project will reduce flooding to approximately 209 homes during a 100-year storm event.

Addison Creek Reservoir and Channel Improvements | MWRD

The 600-acre-foot Addison Creek Reservoir will hold 195 million gallons of storage capacity and connect with the Addison Creek Channel to protect the communities from overbank flooding.

Robbins Heritage Park and Midlothian Creek Restoration Project | MWRD

The MWRD’s Robbins Heritage Park and Midlothian Creek Restoration Project will help address overbank flooding through a new stormwater park and pond, along with improvements to Midlothian Creek and an overflow channel that connects to the Cal-Sag Channel.

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