Experts: Meadowview plan likely to reduce aquifer recharge and harm Barker Creek and Island Lake

KITSAP COUNTY, Wash. Jan. 10, 2025 — Hydrology experts and county staff told the Kitsap County Hearing Examiner on Friday that the Meadowview residential proposal would likely reduce groundwater recharge in the Island Lake aquifer and increase runoff to Barker Creek unless the project redesigns its stormwater approach to favor infiltration.

The Meadowview project proposes residential development on parcels that experts said serve as headwaters for Barker Creek and contribute recharge to Island Lake. Dr. Robert Rosin, a water-resources engineer appearing for the appellants, testified there is "a near certainty that with what's proposed here ... there will be a substantial declining health in Barker Creek," citing the site's size, geology and long-term regional development.

Rosin said the area already shows multi-decade impacts. He described a 30-year decline in lake levels and agency data showing the Silverdale Water District has supplemented Island Lake with millions of gallons of water annually to maintain lake levels. Rosin also pointed to state water-quality listings showing many nearby streams are already impaired and said Barker Creek's upper reach is a remaining relatively healthy stretch supported primarily by groundwater base flow.

County planner Michael Gurney testified that the county did not require a hydrogeological study under current code for this residential development and that the county's stormwater and critical-area rules are the principal tools the county uses to address water impacts. "Code doesn't require hydrogeological study," Gurney said, while acknowledging staff had requested additional information early in the review and had recorded on the permit record that "a hydrogeological study must analyze alternatives to the impacts to Island Lake."

Appellants argued the record lacks a comprehensive, independent hydrogeologic analysis of groundwater recharge impacts to Island Lake and Barker Creek. The transcript includes a public-comment letter that warned "when fifty-five acres of aquifer-recharging forest are stripped and subsequently paved ... aquifer recharge to Island Lake and Barker Creek is significantly adversely affected." Dr. Rosin and counsel said the Meadowview drainage plan relies largely on retention ponds and underdrained bioretention rather than on infiltration practices that restore recharge.

Rosin described the technical basis: empirical studies link watershed impervious cover to stream condition, and infiltration-based best-management practices are the most effective method to maintain groundwater recharge and base flow. He told the examiner that the project's current design pools, pipes and underdrained facilities will capture runoff and export it rather than returning it to the shallow aquifer that sustains Barker Creek's base flow.

County witnesses and applicants have said buffers, stream daylighting and other mitigation measures are part of the mitigation package. Gurney confirmed the Planning Department had imposed a vegetated stream-buffer condition tied to daylighting Barker Creek in its Mitigated Determination of Non-Significance (MDNS). Gurney also said a subsequent hydrogeological study submitted in December 2024 provided additional support for that mitigation but was not available when the MDNS was issued in September 2024.

Why this matters: Barker Creek's upper reach and Island Lake are important local resources for aquatic life and recreation. Experts at the hearing said the Meadowview site comprises a proportionally large recharge area relative to the lake and that increased runoff without infiltration is likely to reduce base flow, degrade stream health and further stress the lake's water budget unless redesigned to prioritize recharge.

The hearing record shows disagreement over whether the county could or should have required a hydrogeologic study earlier in the process. Appellants pressed staff that public SEPA comments flagged the issue and that the permit-review notes initially recorded a requirement for a hydrogeologic analysis; county staff said code and stormwater rules framed what is required for this residential proposal. The Examiner did not issue a ruling at the hearing; additional testimony and filings were scheduled.

The Meadowview matter remains under administrative appeal. The hearing record contains technical exhibits and public comments cited by both sides; the county, the applicant and appellants will have additional opportunities in the proceedings to submit or rebut expert analysis, and the Examiner signaled scheduling to receive follow-up testimony in subsequent sessions.