Wastewater Treatment

Three divisions make up the Wastewater Utility. Utility Billing, which is operated under the Finance Division, and Wastewater Maintenance and Wastewater Treatment, which are operated under the Community Services Department.

The Wastewater Maintenance division maintains all the City's sewer lines and oversees the replacement of older or broken sewer lines. Pictured here is our 2001 Vactor, used to clean sewer lines and catch basins. Keeping the lines and basins clean helps prevent sewer backups, and helps the Treatment Plant to work more efficiently.

The City of Sterling's Wastewater Treatment Plant processes the wastewater disposal of 15,000 residents, 1,500 non-residents, more than 300 commercial establishments and approximately 50 industrial customers. Each day, the plant treats 3.6 million gallons of wastewater per day. 

Our wastewater plant is located on a 50 acre site that includes a 32 acre aerated lagoon. Five lift stations and over 80 miles of sanitary sewer lines flow up to nine million gallons per day to the plant. The treatment plant has been named the top Class III Wastewater Treatment Plant in Illinois twice, and has been nominated seven times for the honor in the past 20 years. A crew of five full-time employees works hard every day to run the best Class III Wastewater Treatment Plant in Illinois.

Call the Wastewater Treatment Plant for assistance with the following:

  • Pre-treatment permits and requirements
  • Questions regarding effluent disposal
  • Any other wastewater disposal questions

The plant is open Monday-Friday 6:00am - 2:30pm. To contact the plant, call (815) 626-8378. For after-hours emergencies, please call (815) 632-6640.

Learn how wastewater is treated by taking a descriptive photo tour