Stormwater Utility Fee Information

The City of Wheaton is proposing to change how it charges stormwater utility fees starting in 2024. Instead of charging based on water consumption, stormwater utility fees would be charged based on the amount of impervious area on each property within the City. Below you will find additional information on the proposed changes and what residents and other property owners can expect. For more information on different fee structures the City considered, as well as their projected effects, please visit the Stormwater Fee Structure Analysis Webpage.

Fee Lookup Tool

The City has created an online interactive map that allows you to search for your property to review the impervious area calculation and estimated fee: 

Stormwater Utility Fee Lookup Map

Stormwater Utility Fee Background

Why does the City charge a stormwater utility fee?
The City charges a stormwater utility fee to support the maintenance and operation of the City’s storm sewer system. The City’s storm sewer system consists of curbs and gutters, inlets, pipes, catch basins, trunk lines, junction chambers, manholes, detention/retention basins, and lift stations. The system is designed to convey stormwater runoff within the City limits and discharge it into one of our four watersheds. The maintenance of this system is necessary to reduce the discharge of pollutants into waterways and mitigate flooding within the City.

How is the current stormwater utility fee charged?
The City’s current stormwater utility fee is based on a property’s water consumption ($0.75 for every 100 cubic feet of water) plus a flat fee of $1.50. For example, if a resident consumed 1,000 cubic feet of water, their stormwater utility fee for that month would be $7.50 + $1.50 = $9.00. Stormwater utility fees appear on the water utility bill as a separate line item.

Proposed Change to Stormwater Utility Fee

How would the stormwater fee be charged in the future?
The City is proposing that the fee be restructured so that it is based on the amount of impervious surface area on each property within the City. This would replace the current water consumption fee and flat fee for stormwater.

What is an impervious area?
An impervious area is any area within a property that prevents stormwater from draining into soil. Examples of impervious area include:

  • Parking lots
  • Buildings
  • Houses
  • Driveways
  • Walkways
  • Patios
  • Decks
  • Swimming pools
  • Gravel, brick, and stone areas

How is impervious area calculated for each property?
DuPage County provided the City with aerial photography that shows every property in the city limits. Using computerized mapping imagery, the City can determine how much impervious area a property contains and calculate that property’s fee.

Why is this new fee structure being considered?
There are three main reasons the City is proposing this change:

  1. Relationship to Service Demands: Impervious area reflects the demand that a property places on the stormwater system better than the amount of water a property consumes. This is because impervious area directly relates to the amount of stormwater runoff a property will generate, and stormwater that cannot be absorbed into the ground must be conveyed through the City’s stormwater system. The more impervious area a property contains, the more runoff it will produce during rainfall, and the more water must be handled by the City’s infrastructure.
  2. Fee Proportionality: This change would create a fee structure that better reflects each property’s impact on the City’s stormwater infrastructure. Under the current fee structure, properties with large amounts of impervious area may pay little to no stormwater fees despite placing a relatively higher demand on the City’s stormwater system. Adopting a fee based on impervious area results in a more even distribution of fees across all property types (i.e., residential, commercial, institutional, industrial).
  3. Revenue Stability: Using water consumption as the basis for a fee means that the funding coming into the City can change, since water usage can vary from year to year. A property’s impervious area is much less likely to change compared to water usage, which allows the City to charge fees consistently for each property and generate a consistent amount of revenue year to year to fund stormwater activities. Furthermore, adopting an impervious area fee would result in a broader fee base (more properties in total paying fees) which will be more stable and dependable over time.

Are there other municipalities that have similar stormwater utility fees?
Yes. Downers Grove, Highland Park, Libertyville, Western Springs, Wilmette, and Winnetka are some examples of other Illinois municipalities that base their stormwater fee on impervious area. According to a 2022 survey from Western Kentucky University, there are approximately 2,050 stormwater utilities in the United States; the majority of these base their fees on impervious area. Adopting a fee based on impervious area would bring the City into alignment with how most other stormwater utilities across the United States operate.

How would fees be calculated for each property?
The billing rate for the fee would be called an Equivalent Runoff Unit (ERU). The ERU reflects the average amount of impervious area on single-family residential properties in the City, which is 3,300 square feet. Each property is then assigned an ERU based on two components:

  1. The amount of impervious area on the property.
  2. The proportion of impervious area on the property.

Fee Component 1: The amount of impervious area on the property, in square feet, is divided by the ERU of 3,300 sq ft. The more impervious area a property has on it, the more stormwater runoff it generates and the more ERUs it will be assigned. For example, if a property has 4,950 sq ft of impervious area, this component of the fee would be calculated like so:

4,950 sq ft / 3,300 sq ft = 1.5 ERU

Fee Component 2: The ratio, or proportion of impervious area on a property compared to the total area of the property. The percentage of impervious area reflects the Intensity of Development on a property. This ratio is assigned an ERU based on the Tiers below.

Intensity of Development Impervious Area % ERU
Tier 0 <1% 0.1
Tier 1 1% - 20% 0.2
Tier 2 21% - 40% 0.4
Tier 3 41% - 60% 0.6
Tier 4 61% - 80% 0.8
Tier 5 81% - 100% 1.0

A property with a higher percentage of impervious area will contribute more runoff to the stormwater system than one with more pervious area and will be assigned more ERUs. If a property has 4,950 sq ft of impervious area and 10,000 sq ft of total area, this component of the fee would be calculated like so:

4,950 sq ft/ 10,000 sq ft = 49.5% = Tier 3 = 0.6 ERU

Each year the City Council would set the fee amount for 1 ERU and each month the property will be billed the fee amount multiplied by the total ERU. Combining Fee Component 1 and Fee Component 2 for each property determines how much it is billed each month. Currently, the City anticipates setting this fee at $4.24 per ERU for 2024 (please note - this amount is an estimate and may change). Using the example property we discussed - that property would pay the following each month:

1.5 ERU + 0.6 ERU = 2.1 ERU x $4.24 = $8.90 per month

Example Fees: Below are several other examples of different properties with different amounts of impervious area to show how much the City expects they would be charged under the new fee in 2024.

Example 1: Residential

Example 1: Residential Impervious Area Diagram

Fee Component 1: 3,200 sq ft / 3,300 sq ft = 1 ERU

Fee Component 2: 3,200 sq ft / 10,049 sq ft = 0.4 ERU

1 ERU + 0.4 ERU = 1.4 ERU

Monthly Fee = 1.4 ERU X $4.24 = $5.94

Example 2: Grocery Store

Example 2: Grocery Store Impervious Area Diagram

Fee Component 1: 74,029 sq ft / 3,300 sq ft = 22.4 ERU

Fee Component 2: 74,029 sq ft / 93,834 sq ft = 0.8 ERU

22.4 ERU + 0.8 ERU = 23.2 ERU

Monthly Fee: 23.2 ERU X $4.24 = $98.37

Example 3: Office Building

Example 3: Office Building Impervious Area Diagram

Fee Component 1: 104,804 sq ft / 3,300 sq ft = 31.8 ERU

Fee Component 2: 104,804 sq ft / 147,799 sq ft = 0.8 ERU

31.8 ERU + 0.8 ERU = 32.6 ERU

Monthly Fee: 32.6 ERU X $4.24 = $138.22

How would monthly fees change under the new fee structure?
The effects of the fee change would be different for each utility customer and property owner.

  • Residential Properties: For residential properties, it would depend on how much water they consumed. Residential properties that typically use small amounts of water each month may see a higher stormwater utility fee under the new structure. Conversely, properties that typically use large amounts of water each month may see a decrease in the utility fee. Overall, monthly fees would be expected to remain roughly the same for most residential property owners.
  • Commercial/Industrial/Institutional Properties: These types of properties typically have large amounts of impervious area with low amounts of water usage. Under the new fee structure, the City expects that the majority of these properties would see an increase to their stormwater utility fee.

How can someone find out how much they would pay under the new fee structure?
The City created an interactive map that is now available where property owners can search their address to find out their estimated stormwater utility fee under the new fee structure.

Would there be any way for property owners to reduce their stormwater utility fee?
The City of Wheaton would offer a “discharge credit” for up to a 50% reduction in fees for a property if the owner can show that none of the property’s runoff discharges to the City’s stormwater system during a 100-year storm event. The City will establish an application form and process for this credit before adopting the new fee. The City will not begin processing requests for a credit until after the restructured stormwater utility fee is adopted. Applications will be reviewed in the order in which they are submitted.

What can someone do if they believe there is an issue with their impervious area calculation or stormwater bill?
The City of Wheaton would establish an appeals process for property owners to:

  1. Contest the amount on their bill
  2. Contest or change the recipient of their bill
  3. Contest the City’s calculation of impervious area for their property

The City would begin processing appeal requests after the stormwater utility fee is established.

Which properties would be required to pay the stormwater utility fee?
All properties that have 250 square feet or more of impervious surface area and are not owned by the City of Wheaton would be required to pay the stormwater utility fee. Either the tenant responsible for the water utility bill would pay the fee or, in instances where there is no existing utility account for the property, the property owner would be required to pay the fee.

Would any properties be considered exempt?
Properties with less than 250 square feet of impervious area, public rights-of-way (e.g., roads, sidewalks, utilities), and City-owned properties would be exempt from the fee.

What is the timeline for implementing the new fee structure?
Below is the City’s current timeline for reviewing and implementing the new stormwater utility fee structure. This timeline is an estimate and may be subject to change:

  • August - September 2023: The City will host public information sessions to discuss the proposed changes to the stormwater utility fee and post disseminate information via its website and utility bills.
  • October 2023: City staff will finalize fee policies and legislation to implement the new fee structure. An interactive map for property owners to look up their estimated fees for 2024 will be made public.
  • November-December 2023: The City will present the fee policies and ordinance to the City Council for adoption.
  • February 2024: The fee change will take effect and begin to appear on utility bills.

Public Meetings, Presentations, and Information

If you would like additional information on the City’s analysis and proposed fee structure you can review several of the previous city council planning sessions that covered this topic:

If you have questions, comments, or concerns about the proposed Stormwater Utility Fee please email