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Chicago Area Waterway System (CAWS)

Sewer outfall into the river.

Over 100 miles of rivers and canals form the Chicago Area Waterway System (CAWS), which connects Lake Michigan with the Mississippi River via the Lower Des Plaines and Illinois rivers. The CAWS includes the Chicago River, the Chicago Sanitary and Ship Canal, the Cal-Sag Channel and the Calumet Rivers.

The CAWS once served strictly as a barge highway and open sewer to carry waste away from Lake Michigan. In the last 20 years, kayaking, canoeing, boating and jet and water skiing have become popular activities on the CAWS, while residential, retail and restaurant developments have popped up along the banks. These new uses have prompted a decade-long debate on improving water quality in the CAWS and Lower Des Plaines River.

June 2013: Motion to Enter Decree

The proposed consent decree requires the Metropolitan Water Reclamation District to complete construction of two reservoirs providing much more "gray" infrastructure storage capacity in the next 6 years than the current storage capacity provided by the tunnels alone. (Click to enlarge.)

On June 7, 2013, the U.S. Department of Justice, on behalf of EPA and the State of Illinois, filed a motion asking the federal district court in Chicago to approve a December 2011 consent decree with the Metropolitan Water Reclamation District of Greater Chicago (MWRD). The settlement will protect public health and improve water quality by capturing high flows of storm water and wastewater from the combined sewer system that serves Chicago and 51 surrounding communities.

The decree requires MWRD to meet an enforceable schedule to complete a tunnel and reservoir plan (known as the Deep Tunnel or TARP). By 2017, MWRD is required to add 8.3 billion gallons of storage capacity -- more than quadrupling its current capacity and significantly reducing combined sewer overflows. All remaining work on TARP required under the consent decree must be completed by 2029.

The decree requires MWRD to distribute rain barrels in urban neighborhoods and to install permeable pavement, green roofs, rain gardens and other green infrastructure measures throughout the MWRD service area. MWRD will prioritize projects to reduce flooding and basement backups, with the highest priority given to neighborhoods where the socio-economic need is greatest. MWRD is also required to develop a comprehensive land use policy to implement green infrastructure on MWRD-owned properties.

The consent decree also requires MWRD to pay a civil penalty of $675,000. The settlement is not final or enforceable unless and until it is approved by the Court.

Public Comments

After publishing the proposed decree in the Federal Register on Dec. 22, 2011, the government received ten sets of public comments. Some groups that provided comments sought permission to intervene in the case. The court granted groups including the Alliance for the Great Lakes, the Environmental Law and Policy Center, Natural Resources Defense Council, Inc., the Prairie Rivers Network and the Sierra Club permission to intervene.

May 2012: EPA Supports Strong Water Quality Standards to Protect Public Health

Map of Effective Water Quality Standards for Chicago Area Waterway System and Lower Des Plaines River

Map of Effective Water Quality Standards for the CAWS and Lower Des Plaines River. (click to enlarge)

EPA has completed its review of Illinois' September 2011 submission of new and revised water quality standards for the CAWS and Lower Des Plaines River. EPA's May 2012 action letter includes the approval of new recreational uses for 8 segments and the disapproval of recreational use downgrades for 4 segments. The May 2012 and November 2011 actions, together, complete EPA's review of Illinois' September 2011 submission.

December 2011: Settlement to Reduce Pollution from Sewage Overflows and Protect Public Health

Chicago's Green Alleys are examples of green infrastructure. They use "permeable pavement" to soak in rain water and reduce sewer overflows. A 1,000 square foot green alley can keep more than 10,000 gallons of water out of the sewer system during any one storm. (Click to enlarge.)

EPA, the Department of Justice, and the State of Illinois announced a Clean Water Act settlement with the Metropolitan Water Reclamation District of Greater Chicago to resolve claims that untreated sewer discharges were released into Chicago-area waterways during flood and wet weather events.

November 2011: Upgraded Water Quality Standards for Portions of the CAWS

Kayakers enjoy paddling in the Chicago River. (Photo courtesy of TheTwoBoxers)

Kayakers enjoy paddling in the Chicago River. (Photo courtesy of TheTwoBoxers)

EPA approved the State of Illinois' new and revised water quality standards for five segments of the Chicago and Calumet Rivers. As a result of EPA's action, after almost a decade of debate, Illinois adopted water quality standards to protect primary contact recreational uses of the waterway - such as kayaking, canoeing, boating and jet and water skiing.


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