Mercer Island city staff presented a joint infrastructure plan for Clark Beach Park and Groveland Beach Park at the Parks and Recreation Commission meeting on May 1, outlining a near-term program of repairs, permitting coordination and community engagement focused on aging overwater structures, shoreline erosion and accessibility improvements.

The infrastructure plan replaces a previously envisioned master plan and targets improvements the city expects to implement over the next 10 to 12 years, allowing early permit coordination and grant applications, project manager Sarah Blubas said. "A park master plan is really that big long‑term vision ... whereas an infrastructure plan is really meant to be near term. So we'll be looking at improvements and enhancements that need to be implemented over the next 10 to 12 years," Blubas said.

Why it matters: both parks have shoreline features built in the 1960s–1970s that city consultants judged to be deteriorated. Staff said the enclosed swim area, pier and sheet‑pile wall at Clark Beach have reached the end of their useful life and are causing shoreline erosion and localized sinkholes under pier surfaces. Groveland's in‑water structures are in generally fair condition after repairs completed in 2018–2019, but show cracking, spalling and local timber and pile deterioration.

Assessments and findings: staff and consultants completed topographic and bathymetric surveys, condition assessments of in‑water structures, geotechnical and critical‑areas reconnaissance, and accessibility audits. Key findings included corroding sheet‑pile wall and asphalt depressions at Clark, localized pile and decking decay at Groveland, and ADA noncompliance at both parks' restrooms (insufficient maneuvering space, inaccessible fixtures, tactile signage issues). Blubas said both sites are mapped as hazardous areas that will require additional geotechnical study before final design.

Community input and schedule: staff reported 229 responses to a fall 2024 online survey that identified beach access, steep access trails, park sanitation and restroom maintenance as leading community concerns. The public engagement plan includes up to two additional online surveys, an open house (in‑person or virtual), postcard mailings to nearby households and targeted outreach; staff said they mailed about 400 postcards to neighbors last fall. Berger Partnership is under contract to develop schematic designs and cost estimates; staff said contracting is wrapping up and work will proceed through summer and fall with a target for plan review and adoption by the second quarter of 2026. Project information and surveys are posted at www.mercerisland.gov/cgip (Let's Talk).

Permitting and funding: staff emphasized that waterfront projects face lengthy permitting with multiple state and federal agencies and tribal consultation; the plan is intended to enable early agency coordination and competitive grant applications. City council previously approved the scope to develop a joint infrastructure plan on March 18, 2025, staff said.

Next steps and tradeoffs: the infrastructure plan will prioritize near‑term capital repairs — particularly in‑water structures — and consider other amenities (restrooms, signage, picnic areas, parking) as resources allow. Blubas noted that if an in‑water structure fails and is removed, replacing it later will be very difficult because of permitting and environmental constraints. Commissioners asked staff to consider whether different waterfronts should emphasize differing uses (for example, fishing or natural shoreline restoration) so the island's three public waterfronts provide complementary experiences rather than duplicating amenities.

The commission will review design alternatives during two future check‑ins and receive a final staff recommendation on a preferred infrastructure plan following public engagement.