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 December 2026, bringing total mitigation efforts over the past decade to $8.6 million, according to officials.

In addition to previous investments, which include commissioning scientific studies, deploying monitoring sensors, and investing in infrastructure at a cost of $3.6 million, a carbon scrubber is currently being installed on shafts near the reservoir to address occasional tunnel odors and a second project involves installing an odor mitigation system that is located along the perimeter of the reservoir to address odors, says the agency’s top administrator.

“On top of our earlier investments, the carbon scrubber and odor neutralizing system being installed at the Thornton Reservoir reflect our commitment to improving the quality of life for nearby residents,” said MWRD Executive Director John Murray. 

Following recent rainfall, the MWRD has been conducting additional odor patrols at and around the Thornton Reservoir. The MWRD’s most recent analytical sensor readings are near zero and in most areas below detection. During certain operational phases, however, odors can be present, according to Murray.

Being a Good Neighbor

“The Metropolitan Water Reclamation District is committed to being a good neighbor wherever we have operating facilities because protecting the quality of life for Cook County residents is vital,” said MWRD Board of Commissioners President Kari K. Steele.

Last week’s rainfall, among others this year, saw nearly 7.4 billion gallons of water captured by the Thornton Reservoir that may have otherwise exacerbated overbank flooding, street flooding, basement flooding and pollution of area waterways, noted Murray.

“Thornton Reservoir helps to protect the quality of life for the residents we serve,” said Murray.