Backflow Prevention Survey
The City is required by the Illinois Environmental Protection Agency (IEPA) and Illinois Plumbing Code to complete a Backflow Prevention Survey. This helps us make sure Warrenville’s drinking water stays safe and clean.
Aqua Backflow will mail a postcard survey to all City water customers in January 2026. This mailing every three years is a requirement of the IEPA.
What is backflow?
Backflow happens when water flows the wrong way—backward from a private plumbing system into the public water supply. This can allow chemicals or other contaminants to enter the drinking water. It can occur when things like irrigation systems, fire sprinklers, boilers, or other equipment are connected to the water supply without the right protections.
Why is the survey important?
The survey helps us find properties that might have a backflow risk and confirm that the correct prevention devices are in place and working properly.
Who needs to take part?
All property owners—residential, commercial, and industrial—are asked to complete the survey. The answers you provide will help us know if extra protection is needed at your property.
This survey is required by the State of Illinois to protect everyone’s drinking water from possible contamination.
Learn more on the City's website at: https://www.warrenville.il.us/869/Lawn-Irrigation-and-Cross-Connection-Con