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Sammamish Town Center (not licensed)

Storm and Surface Water Projects

Sr. Stormwater Program Manager

Stephanie Sullivan
(425) 295 0560
recently installed stream restoration project with culvert under trail, stakes planted on the streambank, and rocks and a log in the creek
New box culvert for Ebright Creek crossing underneath East Lake Sammamish Parkway

Stormwater capital projects are developed through a strategic planning process. Each project begins as a maintenance issue or identified need through basin planning, drainage complaints, or other studies.

To become a project, a planning-level assessment is completed to prioritize the project for implementation. We estimate the amount of time and cost needed to realistically finish the project. The project can then be added to the 6-year Stormwater Capital Improvement Plan. Using this plan, the projects are programmed into the Stormwater Division's 2-year budget and work plan.

6-Year Stormwater Capital Improvement Plan

The DRAFT 2025 - 2030 6-year Stormwater Improvement Plan is available for public review below.

City Council will open the public hearing on June 4, 2024 during their regular Council Meeting.  It is expected that the public hearing will be continued to June 18, 2024 at which time Council will make a decision.  The public is invited to provide written comment until 5:00 pm, June 18, 2024 (the last day of the continued public hearing).  Submit your written comments by email to the City Clerk at and

Capital projects address site-specific issues, such as flooding or necessary repairs. These projects are included in the City’s six-year Stormwater Capital Improvement Plan (CIP).

Maintenance Projects

The Operation and Maintenance Manager and the Senior Stormwater Program Manager jointly oversee operations and maintenance of City-owned stormwater facilities. Work is accomplished by City inspectors, maintenance crews, and contractors.

Maintenance activities are required at several hundred facilities. Activities include managing vegetation, removing sediment and debris, and repairing erosion with grading and stabilization. Additionally, materials and infrastructure sometimes need to be replaced. Cartridges and filtration material (sand filters, bioswales) must be replaced periodically. Likewise, infrastructure such as catch basins, manholes, inlets, and outlets require maintenance and replacement.

Planning Projects

The City of Sammamish is working on several planning projects related to stormwater. Project pages will be developed as more information is available.

Basin Plans

Basin plans provide comprehensive analysis of surface water characteristics, issues and solutions to identified problems. The framework for the plans are the area where water naturally drains (i.e. the drainage basin).

The East Lake Sammamish Basin Plan was completed by King County in the early 1990s. The City updated several sub-basins included in that plan (including Inglewood and Thompson) in 2009.

Additional plans are prioritized and continue to be added to update conditions that have changed since the 1990s. Updates provide new analysis and recommendations to protect natural resources and improve water quality and drainage concerns.

In the 2023-2024 biennial budget, the Stormwater program plans to complete one basin plan every two years.

King County Plans and Reports

The City of Sammamish was incorporated in 1999. For several years, the City contracted with King County through an interlocal agreement for stormwater services. The City still contracts with King County for stormwater billing and other support.

List of Storm and Surface Water Projects