Tumwater committee backs placing Well 15 aeration design agreement on council consent calendar

Carrie Gillum, the city’s senior water resources specialist, told the Tumwater Public Works Committee on Feb. 19 that the city is seeking a service-provider agreement with Gray & Osborne for design work to add aeration treatment at Well 15 and to rebuild the wellhouse.

The design, Gillum said, would include aeration treatment to address pH-related corrosion concerns identified in an HDR optimization study, a replacement of the existing wooden wellhouse to improve earthquake resilience and security, SCADA and cybersecurity upgrades, and auxiliary power for emergency operation. Well 15 is one of the system’s largest producers and is located northeast of Tumwater Boulevard on property owned by the Port of Olympia under a perpetual easement, Gillum said.

The work responds to the federal Lead and Copper Rule framework and state implementation: Gillum said HDR’s study — completed in 2024 — found that three wells in the Port well field require corrosion-control treatment primarily because of pH conditions. The Washington State Department of Health accepted HDR’s recommendations and set a design-and-construction timeline that requires work to be in place by July 29, 2026.

Gillum recommended placing the Gray & Osborne service-provider agreement on the March 3, 2026 city council consent calendar with authorization for the mayor to sign. She said design funding would come from the city’s Drinking Water Fund and is “not to exceed $368,000.” Committee members asked about sampling volunteers and whether other wells would require treatment; Gillum said the next round of volunteer sampling is scheduled for 2028 and that other Port wells (9 and 10) will be evaluated after Well 15 is addressed.

"This is for the Well 15 improvement project, which is going to include a few different pieces to it," Gillum said during her presentation, adding that Well 15 "is our second largest single producing well in the water system."

The committee voted to place the agreement on the March 3 consent calendar; the motion passed with ayes recorded and the item will be considered by the full council on March 3.