Arboretum Creek Project Receives $1.1 Million in County and State Funding

Last month, the King County Flood Control District approved a grant of $889,000 to Seattle Parks and Recreation for the construction phase of the Arboretum Creek Headwaters Project. While earlier this year, the Washington State Department of Ecology approved a $220,000 Water Quality Grant to complete project design details.

King County has already provided substantial grants for the Headwaters Project, as we reported a year ago. Total funding raised for the project so far is now approaching $3 million.

The project goal is to restore the natural hydrology of Arboretum Creek by reconnecting it to two neighborhood springs—Alley and Alder Springs—that were originally part of the creek’s historic watershed. With the help of new piping and an innovative subsurface gravel wetland, the project will also capture and treat stormwater runoff that currently causes localized flooding—including in the Japanese Garden—and redirect it into the creek. Clean water flowing year-round will help bring a diversity of lifeforms back to the stream and revitalize its ecology.

Because of generous funding from both public and private sources (see below), Headwaters is proceeding apace. According to Seattle Parks and Recreation project page, the consultant engineering and design team, Jacobs Engineering, has finalized the 60-percent construction drawings and is working toward 90-percent documentation and permitting approval. Geotechnical investigations, arborist tree assessments, wetlands reconnaissance, and existing drainage structure video inspections have been completed to help inform the design.

Construction is scheduled to begin in 2027, contingent on permitting and additional construction funding.

Volunteers from the Friends of Arboretum Creek during their October monthly work party. (Photo courtesy FOAC)

“We still have to raise about $2.9 million to completely fund the construction,” says Larry Hubbell, the co-founder of the non-profit Friends of Arboretum Creek, which is the brainchild behind the project. “But we are very hopeful. Seattle Parks and Recreation, with continued support from the Friends of Arboretum Creek, has applied for additional Water Quality funds from the Washington State Department of Ecology. We will learn more in mid-2026.”

Part of that price tag, explains Larry, is the effort required to test, validate, and then seek Department of Ecology (ECY) approval of the project’s innovative sustainable water treatment process as a new ECY Best Management Practice. “If our gravel wetland gets approved, the technology could be used on other water quality projects around the state, which is very exciting.”

“A huge thank you to the King County Council, especially D2 Council Member Girmay Zahilay, for approving the recent Flood Control Grant, and to Washington State for its Water Quality Grant,” says Larry. “Additional thanks to the Arboretum Foundation, the Aldarra Foundation, the Chabot Family Fund, Dick Eitel, the Japanese Garden Society, Rick and Anne Matsen, the Seattle Parks Foundation, and the Peach Foundation, as well as to the many dozens of individuals who have donated time, money, and hard work to this creek restoration effort.”

Niall Dunne is the communications manager and Bulletin editor at the Arboretum Foundation.