Comment Period Extended For Chicago Dredge Material Plan

The Chicago Engineer District has extended the comment period for the Chicago Area Waterway System (CAWS) Dredged Material Management Plan (DMMP), and integrated Environmental Impact Statement. Comments were originally due on June 17, but the new closing date is July 2.

The purpose of the study is to identify and evaluate alternatives for dredged material management for the CAWS, which is made up of six federal navigation projects: Calumet Harbor and River; the Calumet-Saganashkee (Cal-Sag) Channel; Chicago Harbor; Chicago River; the South Branch of the Chicago River; and the Chicago Sanitary and Ship Canal. The Corps analyzed alternatives that could safely confine 20 years’ worth of dredged material generated in the operation and maintenance of the federal navigation channels of the CAWS.

An annual average of 50,000 cubic yards (cy.) of sediment is dredged from the Calumet Harbor and River and placed in the Chicago Area Confined Disposal Facility (CDF). Ongoing shoaling in the Cal-Sag Channel is expected to create a minor additional dredging need within the next 10–20 years, the Corps said.

Life-extension measures are being utilized at the existing facility and a new plan for placing material is needed to allow dredging to continue beyond 2022, when the existing facility is expected to close.

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A Draft DMMP was first released for public review on June 9, 2015. However, the tentatively selected plan from the 2015 Draft DMMP is no longer feasible, so the Chicago District revisited the site-selection process to determine whether conditions had changed in the project area and whether other potential sites may have become available since 2015. In addition to the sites previously analyzed, the Chicago District sought to identify additional sites for analysis in the project area through a public involvement campaign with stakeholder organizations and local residents in 2018.

The new proposed plan includes a recommendation to build a replacement sediment facility to contain sediment dredged from the Calumet River and Cal-Sag channel on the same footprint as the existing Chicago Area CDF. Calumet Harbor sediment, which is suitable for upland use as clean fill, would be used beneficially as construction material for the new sediment facility and as cover for the existing CDF during closure. No material suitable for beneficial upland use would be placed in the new facility.

The total amount of dredging anticipated to occur over the 20-year study period is 1,030,000 cy. The total facility capacity will be about 530,000 cy. for contaminated dredged material. The capacity reserved for Cal-Sag Channel sediment, whose quality is similar to that of the Calumet River, is approximately 3 percent of the overall dredging need in the study area over 20 years. While Cal-Sag Channel dredging may not be necessary over the life of the proposed facility, space is required to ensure that the connection between the Great Lakes and the inland waterway system can be maintained.

The draft report and appendices, as well as details on how to submit comments, can be found on the study website at: https://www.lrc.usace.army.mil/Missions/Civil-Works-Projects/Calumet-Harbor-and-River/.