Stormwater Utility

Since every property contributes stormwater, every property owner helps to pay for the flooding solutions. Stormwater utilities have become more common throughout the State, as they provide a predictable and sustainable funding source to maintain and improve a stormwater system. 

The Village bills property owners for stormwater utility services based on the amount of impervious surface on the property. “Impervious surface” is calculated as an Equivalent Runoff Unit (ERU). One ERU equals 3,400 square feet of impervious surface. The fee appears on each customer’s regular utility bill, along with Village fees for water, electric, sanitary sewer, etc. Winnetka’s stormwater utility is a set fee: $21.83 per ERU, per month, with most residential customers billed bimonthly.

Stormwater Utility Credits

Residents may receive credits for:

  • Detaining and cleaning no less than half the property’s stormwater runoff during a 100 year storm event
  • None of the property’s stormwater draining into the Village’s stormwater system

In order to do so, the following forms/materials should be consulted:

Stormwater Utility Appeals

Appeals can be made if:

  • Billing errors occur
  • Miscalculations occur in billing or impervious area calculation
  • Property is classified incorrectly

Utility appeals (PDF) can only be made after a homeowner has been billed. Appeals missing the required information or that do not meet the appeal criteria will be returned to the applicant without review. Completed and signed forms should be returned to the address indicated on the form. Electronic documentation will be accepted. Please allow 30 days from submittal for appeal review.


Questions about either the appeal or credit processes should be directed via email to the Village’s Stormwater Utility Customer Support team or call at 847-716-3549.