Public Works: Stormwater Management & Erosion Control


The City of Onalaska completed a Stormwater Management plan and associated Ordinance in 2008.  This plan lays out future stormwater projects and policies. 

In October of 2009 the City of Onalaska passed a Stormwater Utility Ordinance that became effective January 1, 2010.  At the December 2009 Common Council meeting the ERU (Equivalent Runoff Unit) was approved for 2010 at $50.95 per year.  All single-family and duplex properties are charged one ERU per year.  Remaining properties are charged based upon the amount of impervious area (roof, paved parking, sidewalks, etc.) divided by the average impervious area of a typical residential property (3,888 square feet).   


Below are links to the City of Onalaska's Erosion Control & Stormwater Management requirements and documentation. Submittal requirements for all developments are contained in the links below. Please refer to these documents when submitting designs to the Engineering Department for review.

For copies of the complete Stormwater Quality Management Plan (104 MB), Appendix J - Documentation of Detention Basin Field Review (227 MB), or both, email your request, with your mailing address to: Kevin Schubert, City Engineer at e-mail.  Your materials, including an invoice for $25 to cover the data/mailing cost, will be sent you.


City of Onalaska Stormwater Utility Frequently Asked Questions

1. What is stormwater management?

Stormwater management is effectively managing the quantity and quality of stormwater runoff within and leaving the City. Stormwater is surface flow (runoff) that occurs from rain or snow melt events. Runoff within the City flows over land or streets to a municipal collection system consisting of pipes, ditches, culverts, swales, and detention facilities, ultimately discharging to the La Crosse River, Lower Black River, Mississippi River, or Lake Onalaska. The City performs a wide variety of services to carry out stormwater management activities as follows:

a. Maintenance

• Cleaning, repairing, and replacing storm sewer manholes, inlets, and pipes.

• Constructing new storm sewer projects.

• Mowing ditches.

• Cleaning brush or debris from drainage ways where allowed.

b. Water Quality Practices

• Street sweeping.

• Leaf collection.

• Inspecting and enforcing construction site erosion control standards.

• Maintaining stormwater detention basins.

c. Planning and Engineering

• Engineering studies to determine the size and type of structures that must be used to improve the drainage system and reduce risk of flooding.

• Reviewing and approving land development stormwater management practices.

• Water quality studies to determine the areas where pollution reduction practices must be utilized along with other state requirements to meet Wisconsin Department of Natural Resources (WDNR) permit goals.

2. Why have a Stormwater Utility?

A Stormwater Utility provides a fair and equitable way of collecting revenue for stormwater management system improvements under which property owners are charged a user fee based on the amount of stormwater “produced” on their property. All property owners pay their fair share of stormwater management costs, similar to a water or electric utility. Previously, stormwater costs were paid for through the property tax roll, placing a majority of the burden of paying for stormwater management on the residential sector. The Stormwater Utility reallocates the cost of stormwater management to the properties that drive the service costs, such as commercial, industrial, and other properties with large impervious surfaces. The Utility also charges tax exempt properties, which currently do not contribute to stormwater management but are typically associated with generating significant runoff such as government property, schools, and churches. Cont.

3. Why not continue to include stormwater management costs as part of the General Tax Fund?

Until 2010, the costs of expansion, operation, and maintenance of the City’s stormwater management system were paid for by property taxes through the General Fund. Increasing pressures on the general fund caused by rising municipal costs and reduced revenues from the State of Wisconsin may make the General Fund a less reliable source for stormwater management funding. In 2006, the City of Onalaska was issued a Wisconsin Pollution Discharge Elimination Permit (WPDES) for stormwater discharges to the water of the State of Wisconsin that requires the City to implement stormwater regulations as administered by the WDNR. To meet the requirements of the WPDES permit, the City Council formed the Stormwater Utility. The Stormwater Utility charges a fee as a means of addressing stormwater management funding needs without placing an additional burden on property taxes. Unlike property tax funding, user charges under a Stormwater Utility are established in proportion to the relative amount of stormwater runoff “generated” by an individual property. Without the Utility, other City services funded by property taxes would have needed to be reduced.

4. When was the Stormwater Utility created?

The utility was created by ordinance in October of 2009 and became effective January 2010.

5. Who has the authority to approve the Stormwater Utility budget?

The Common Council will serve as the Stormwater Utility board. All policy and budget decisions must be reviewed and approved by the elected officials of the Common Council.

6. Have other cities created stormwater user fees?

As of 2010, more than 71 utilities have been established in Wisconsin communities to fund their stormwater management programs. User fees for stormwater services range from $15.00 to over $100.00 annually for the base equivalent runoff unit (ERU) charge.

7. How is my Stormwater Utility charge determined?  How often will I be billed?

Stormwater fees are based on the amount of impervious surface on each property. Therefore, properties with a greater amount of impervious area generate a greater amount of stormwater runoff resulting in a higher impact on the stormwater drainage system. Impervious surfaces include roofs, private sidewalks, private streets, driveways, patios, and parking lots. The impervious area for all nonresidential parcels (commercial, institutional, etc.) and multifamily parcels was measured and a sample of the single-family residential parcels was measured from an aerial photo and supplemented using site plans.

The Stormwater Utility charge is based on an ERU. An ERU is defined as the average impervious area of a single-family home. A sample of the single-family residential parcels was measured from an aerial photo and the average impervious area of a single-family home in Onalaska was determined to be 3,888 square feet. Thus, 1 ERU = 3,888 square feet for the City’s Stormwater Utility rate structure. The charge per ERU is $4.25 per month, or $50.95 annually, and will be billed on a quarterly basis.

8. What are the components of the Stormwater Utility fee?

The stormwater user fee includes three distinct components:

a. Base Component The base component includes the Stormwater Utility’s estimated annual administrative and management costs, water quality costs, and other miscellaneous costs. Costs associated with the new WDNR requirements are included in the base component.

b. Operation and Maintenance Component The Operation and Maintenance (O&M) component includes the utility’s estimated annual operation and maintenance costs for the City’s stormwater management system, including storm sewer and detention basin maintenance, street sweeping, and so on.

c. Capital and Debt Service Component This includes capital costs and debt service payments for the City’s stormwater management system.

9. What is the stormwater fee for an average single-family homeowner?

Under the current ordinance and resolution, single-family residential homeowners will pay $50.95 annually. This includes duplexes that under the Stormwater Utility ordinance would receive 0.5 ERUs per unit or 1 ERU per lot. The rate will increase in subsequent years, with approval from the City Council as additional services are included in the Utility and to fund planned capital improvement projects to comply with current WPDES permit requirements.

10. How is a nonresidential property charged for stormwater?

The nonresidential classification includes properties such as commercial, intuitional, and manufacturing. Nonresidential also includes tax-exempt properties, mobile home parks, and multifamily dwellings with three or more units. An ERU is considered to be the average impervious area present on a single-family residential parcel based on measurement of a random sampling of residential parcels within the service area. ERUs are assigned to nonresidential parcels based on dividing the actual measured impervious area by the average impervious area for a typical single-family residential parcel. For example, in the City of Onalaska one ERU is based on an average residential impervious area of 3,888 square feet, therefore a nonresidential parcel with 38,880 square feet of measured impervious area would be assigned 10 ERUs (38,880 square feet divided by 3,888 square feet = 10 ERUs). In this way, a nonresidential parcel having ten times the amount of impervious area of a typical single-family residential parcel will pay ten times the average residential charge for stormwater management.

11. Can I reduce my fee by controlling runoff from my property?

Single-family homes and duplexes are not eligible for a fee reduction. This is because there are benefits to all property owners that are paid for by the utility, such as street sweeping, leaf collection, and general system maintenance. A system of credits was established when the Stormwater Utility was created to reduce the fee in certain circumstances, such as properties with detention basins. To be eligible for a credit, a property must meet the criteria set in the City of Onalaska Stormwater Utility Credit Policy.

12. Does the credit policy reduce the fee of all the fee components?

No. Credits shall be applied only to the capital and debt service (8c above) and operation and maintenance (8b above) components of the Stormwater Utility fee. Properties qualifying for a credit are still responsible for the base component (8a above) unless the applicant can demonstrate the property is regulated by a separate municipal Stormwater Discharge Permit (WPDES). See the City of Onalaska Stormwater Utility Credit Policy for additional information.

13. What if my property never floods, will I still have to pay a stormwater fee?

All developed property in Onalaska pays a Stormwater Utility fee regardless if a drainage concern exists on that specific property or not. Even if your property has never flooded, the stormwater that flows off your property must be managed so that it does not contribute to flooding in areas downstream.

14. Who can I contact for additional information?

Contact City Engineer, Kevin Schubert, for more information. He can be reached at (608) 781- 9537, or by e-mail: