Private Stormwater System Maintenance

Neighborhood Stormwater Pond

What is required?

Property owners are responsible for cleaning and maintaining their private stormwater system and must submit a Stormwater Facility Maintenance Summary Form and required documentation by July 31 of each year.

Stormwater systems are the infrastructure that capture and transport 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 sometimes filters.

What are the benefits of maintaining your Stormwater system?

  • Prevent damage to the stormwater system and costly repairs.
  • Prevent flooding on the property.
  • Reduce liability by preventing water-related damage to downstream properties.
  • Reduce pollution in local aquifers, streams, lakes, wetlands and Puget Sound.
  • Reduce erosion of stream banks and channels, which harm aquatic life and property.

To keep your stormwater system functioning properly and stay in good standing with your City agreement, follow these steps:

1. Inspect your stormwater system
Select the appropriate sections from the Stormwater Facility Checklist that apply to your system.

2. Perform maintenance and fix problems
Some maintenance requires a qualified or certified service professional, such as treatment vaults and filters (view inspection and maintenance specs). You may need to contact different contractors for different types of services.

This list of vendors is maintained by Thurston County and does not imply endorsement by the City. Please do your own reference checks and verification when selecting a contractor.

3. Submit required documentation
Complete the Summary Form and return it with checklists, invoices and photos to:

  • Email:
  • Mail: Olympia Public Works, Stormwater Management
            P.O. Box 1967, Olympia, WA 98507

Note: You are required to provide proof/invoices for all media filter and treatment cartridge replacements.

Screenshot of stormwater system map

Stormwater system map

This online stormwater system map allows you to see what assets make up your private stormwater system facility. It can be used to help you resolve issues and maintain you stormwater system.


Contact Kane Osstifin at 360.753.8579 or

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