Tumwater updates Barnes Lake management plan; steering committee additions and targeted vegetation treatments planned

City staff gave the Tumwater Public Works Committee an informational update on Barnes Lake Management District activities on May 8, 2025, covering monitoring upgrades, vegetation-control plans and near-term maintenance and outreach events.

The report described routine and special treatments to control invasive aquatic plants, upgrades to monitoring equipment and community outreach plans, including a Sept. 10 lake walkabout for steering-committee members and residents.

David (first name only in the transcript), a staff member reporting for the Barnes Lake Management District, told the committee the district is beginning its 2025 work plan. He said two new steering committee applications are in process: Sherry McCafferty from the Northeast neighborhood (Daisy Lane) and Matt Brownell from the West neighborhood (Lake Park Drive). A newsletter went out by mail and Constant Contact, he said.

Staff described monitoring upgrades for the season, including a YSI multiparameter meter to measure dissolved oxygen and temperature and a HOBO data logger that remains in the water to record continuous lake levels and temperature. David said a recent data gap in the logger record was caused by depleted batteries that have since been replaced.

On vegetation management, staff said the district conducts routine treatments of diquat and imazomox targeting invasive bladderwort and fragrant water lily. Every three to five years the district applies fluridone, a more expensive targeted treatment; staff said the district plans to use fluridone this year but that the fluridone application is going through management approval. Staff provided a rough budget comparison: routine chemical treatments were quoted at roughly $14,000 (vendor estimate), while the fluridone treatment would increase costs materially (no single figure for fluridone was provided in the presentation).

David said staff is pursuing permitting to improve the boat launch to accommodate the wider boat used for treatments. He also said the district will update its integrated aquatic vegetation management plan, which was prepared about 10 years ago, to guide future plant management decisions.

The committee discussed a Sept. 10 lake walkabout for the steering committee and interested members to view the lake from multiple vantage points. David encouraged participation; he also offered a light-hearted, on-the-record description of cattail foragers: “It's like celery. Honestly, it's really it's really crisp and light, and, it's you can only eat the white part down there at the at the very bottom,” he said.

Staff noted the district is in its second year of contracting with Aquatechnics for treatments; staff contrasted Aquatechnics’ regional experience with the previous local contractor, Northwest Aquatic Ecosystems. Patrick Soderbergh, speaking from his county experience, said Thurston County oversees other lake management districts including Long Lake and Lake Lawrence and that Black Lake uses a special district structure to self-manage.

The presentation was informational only; no committee action was requested or taken. Committee members discussed scheduling a field visit to Barnes Lake for a future Public Works Committee meeting and confirmed interest in attending the Sept. 10 walkabout.