Updated: 10/30/2025

Overview

The multi-phase Locust/Colton CSO project involves construction of new sanitary sewers, conversion of the existing combined sewer into a storm sewer, and laying new water main. The sewer portion of the project, with nine phases, is projected to cost nearly $22 million and last through most of the decade. Click here to view a map.

 
A combined sewer overflow (CSO) can occur when storm water run-off combines with the sanitary flow, usually during a heavy rain event, and discharges to an open body of water such as a creek or stream (left image above). This project continues the work of installing new sewer lines to separate the sanitary flow from the storm flow so that all sanitary flow is treated at the Bloomington Normal Water Reclamation District (BNWRD) Waste Water Treatment Plant (WWTP) prior to being discharged to Sugar Creek (right image above). In addition, older water main will be replaced within the project limits while the area is under construction. Click here to view the Sanitary Sewer page to learn more about Combined Sewers and Combined Sewer Overflow.

Phases 1-7

Phases 1, 6, and 7 were completed in 2013. Click here to view the location map.

Phase 2 was completed in 2022. Click here to view the location map.

Phase 3 was completed in 2023. Click here to view the location map.

Phases 4-5 were completed in 2025. Click here to view the location map for Phases.

Phase 8

Design for Phase 8 began in July 2023. Additional information will be added as the phases progress.

Phase 9

Design for Phase 9 has not begun at this time. Additional information will be added as the phases progress.