Collection System RegulationsBeginner 10 min read

Illinois Collection Systems: A Voluntary Credential in a Combined-Sewer State

Illinois collection system certification is voluntary, not mandatory — but Chicago-area operators still need to understand how their work interacts with MWRD's combined sewer and Deep Tunnel system, and downstate operators face their own I&I challenges.

Illinois Collection System Operations

A Voluntary Certification

Unlike Illinois's mandatory drinking water and wastewater treatment operator certifications, the Collection System Operator credential is voluntary. Illinois EPA strongly recommends certification, but a system is not legally required to employ a certified operator to run its sewer collection network. The Collection Systems exam covers 100 questions and, unlike treatment certifications, carries no continuing education (CEU) requirement.

Two Different Operating Environments

Chicago metro (combined sewers): Much of the Chicago area runs a combined sewer system, carrying both sanitary sewage and stormwater in the same pipes. This system is managed alongside the Metropolitan Water Reclamation District's Tunnel and Reservoir Plan (TARP) — the Deep Tunnel — which is specifically engineered to captu

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