By Townhall Chicago News Staff
The Metropolitan Water Reclamation District of Greater Chicago broke ground on a nearly $400 million wastewater treatment project at its Terrence J. O’Brien Water Reclamation Plant in Skokie, marking one of the largest single infrastructure investments in the agency’s 137-year history.
The project, known as Battery E, is a four-year effort that will add aeration tanks, final settling tanks, ancillary structures and supporting equipment to the facility, which first opened in 1929, according to an Oct. 20 report on the MWRD website. The MWRD broke ground Oct. 8.
The primary goal is to reduce phosphorus concentrations in treated wastewater before it is discharged into the North Shore Channel. Excessive phosphorus in waterways can contribute to algae growth, deplete oxygen levels and harm aquatic ecosystems. The North Shore Channel connects to the North Branch of the Chicago River and the wider regional waterway system.
“As the O’Brien Water Reclamation Plant approaches 100 years of service, we are making an investment that will help ensure this facility is prepared for the decades ahead of protecting public health and our waterways,” MWRD President Kari K. Steele said in a statement.
The project will use naturally occurring microorganisms to remove phosphorus during wastewater treatment through a process called enhanced biological phosphorus removal. The additional capacity will also allow the district to take existing treatment infrastructure offline for rehabilitation.
Three of the plant’s four existing treatment batteries are approaching 100 years old. The MWRD plans to upgrade Batteries A, B and C in phases beginning in 2031.
The upgrades will help the district meet new phosphorus discharge limits taking effect in 2027, with stricter requirements scheduled for 2030. The U.S. Environmental Protection Agency and a federal task force are pursuing a 45 percent cut in nitrogen and phosphorus reaching the Mississippi River basin by 2035. The MWRD estimates that nutrient removal technologies at its three largest facilities, including O’Brien, will deliver 20 percent of Illinois’s reduction goal, according to Smart Water Magazine.
The O’Brien plant serves more than 1.3 million people in Evanston and surrounding municipalities.
Commissioner Cameron Davis said the project benefits extend beyond water quality.
“It’s a big investment in the health of our waterways, jobs, and helping our downstream neighbors,” Davis said in a statement.
Battery E is expected to create work for skilled trades including electricians, ironworkers, laborers, millwrights, operating engineers, pipefitters, plumbers, steel erectors and truck drivers.
The district began related process improvements in 2023 with work on Battery D, including a sidestream fermentation zone. That work is expected to be completed in 2026. The MWRD also awarded a contract in 2025 for a chemical backup system to provide additional support in meeting discharge requirements.
State and local leaders attended the groundbreaking ceremony, including Evanston Mayor Daniel Biss and Skokie Mayor Ann Tennes, according to the Evanston RoundTable.
The MWRD also hosted Illinois lawmakers for a tour of wastewater and stormwater infrastructure the same week, giving members of the General Assembly a firsthand look at facilities that protect public health and the environment across Cook County.
Source: MWRD News
