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Stormwater Utility and Inspection

Questions on Stormwater maintenance requirement or potential enforcement actions? Please see the City's Stormwater Policies and Regulations page.

NOTICE! Registration is required for businesses to be eligible for the stormwater rate credit of up to 35% (refer to SMC 21.03.050.E.5-6)

Non-single family residential parcels are not eligible for the rate credit.

Stormwater Utility Rate Fee

The goal of the City’s Surface and Stormwater Program is to protect and restore our local water resources by ensuring a high-performance level from current and future stormwater systems. This can reduce flooding and prevent polluted runoff from reaching our streams, rivers, wetlands, and Puget Sound.

Without regular maintenance and inspection, your system can become compromised. This can allow water to directly discharge into local streams without sediment and pollution control. An unmaintained system could cause flooding on your property and those around you, resulting in costly damage or loss.

Do you manage a privately-owned stormwater system? Please register your contact information here!

Stormwater Utility Rate Study

A new utility fee was adopted with the annual Fee Schedule in November. Please refer to the fee schedule for current rates. An enhanced level of service was adopted by City Council on October 18, 2022.  Please check the City Council calendar for more details.

Stormwater Utility Rates And System Development Charges

Surface water fees are authorized per SMC 21.03.050. The information listed below is provided as a courtesy. Please refer to the City's fee schedule for the adopted rates.

2024 Stormwater Rates
  Rate Unit
Residential $447.05  
Non-Residential $447.05 Per equivalent service unit (ESU)*

*One equivalent service unit (ESU) is equal to 3,500 square feet of impervious surface. Properties measured to have less than 1 ESU of impervious will be charged a minimum fee equal to the unit rate.


Surface Water Development Charge 
New residential dwelling unit or commercial building with up to 2,500 square feet of impervious coverage $3,654.00
Each additional 250 square feet of impervious coverage over 2,500 square feet $365.40
Other structures or additions of up to 250 square feet of impervious coverage requiring a building permit $365.40 plus $365.40 for each additional 250 square feet
Surface Water Retention Locks $36.00 plus tax

Private Stormwater System Maintenance

Private Stormwater System Inspection

Stormwater systems collect stormwater runoff before it flows into our streams, lakes, and Puget Sound. Private stormwater systems often include features such as stormwater ponds, swales, ditches, pipes, catch basins and other waterways, including groundwaters that flow beneath our feet.

Stormwater systems protect property and buildings from flooding. Rainfall accumulates on hard surfaces like roofs, streets, and parking lots. If there were no drains, these buildings and properties would flood when it rains.

What is required?

Owners must clean and maintain their stormwater system.

How to Meet the Requirements


  1. City Inspection.
    • Each year, the City performs an inspection to identify maintenance needs.
    • A Maintenance Correction Letter (MCL) is sent to owners for facilities needing maintenance. To keep your stormwater system functioning properly, you must perform these maintenance activities.
    • If you have not registered contact information, are a new facility owner, or would like to change or verify your contact information please visit: stormwater-registration.
    • To receive a maintenance credit on your stormwater bill, you must complete maintenance by October 31st and register your contact information with the city.


  1. Perform the maintenance.
    • Some maintenance requires a qualified or certified service professional, such as treatment vaults and filters. You may need to contact different contractors for different types of services.
    • Note: You are required to provide proof/invoices for all maintenance completed including but not limited to media filter and treatment cartridge replacements.


  1. Submit required documentation.

Coming soon: Frequently Asked Questions