Proposition W, the Water Line Insurance Program, passed in the April 6, 2021, Municipal Election. The fee related to this program will not be collected until December, while the new program does not take effect until January 2022. Learn more about the program.

The City of O'Fallon Water and Sewer Department provides water and sewer service to parts of O'Fallon City limits. Use our Address Look-Up to determine services for a selected address.

Water and Sewer emergency, main break or sewer backup?

Please call 636-379-5488.



Frequently Asked Questions

Can I flush disposable wipes down the commode?

Can I tour the Water or Wastewater Plant?

Does the City water system add fluoride to the water?

How is my water metered?

How is sewage usage determined?

How often do the bills go out?

We are moving. How do we disconnect our services?

What is the difference between a boil advisory and a boil order?

What is the hardness of the water in O’Fallon’s water system?

Where are my water and sewer lines?

Why am I losing water pressure in my home?

Why has my water bill gone up?

Why is my sewer charge higher than my water?

Why is my water discolored today?

Why is there a security deposit on my first bill?