City staff outline multi‑strategy waterfront adaptation plan to address erosion and sea‑level rise

Timmy Bolton, senior climate adaptation analyst and project manager for the Waterfront Adaptation Plan, told the Historic Landmarks Commission that the three‑mile project area from Ledbetter Beach to the Clark Estate is one of the city's most valued public assets and increasingly vulnerable to waves, erosion and inland flooding.

"It's to develop practical solutions to address coastal flooding and coastal erosion for at least the next 30 years while enhancing beach access, recreation, boating, and habitat," Bolton said, summarizing the project vision and the balance the team is trying to strike between hazard protection and public access.

Bolton said the project uses new, higher‑resolution technical modeling developed for the city and that results show historic erosion on East Beach in some stretches of roughly five feet of beach width lost per year relative to 2000. He described a set of sea‑level rise scenarios used in planning — roughly 0.8 feet by about 2050, 1.6 feet by about 2065 and 2.5 feet by about 2075 — and said the plan focuses on a 30‑year planning horizon where the most urgent interventions are expected to be required.

The presentation divided options into "quick wins," core measures and future options. Quick wins include restriping parking to create separated walking and biking facilities, temporary deployable flood protections and minor drainage work. Core measures under study include elevated walking and biking paths that would double as a vertical flood defense, beach nourishment and, in constrained areas such as the harbor commercial zone, a rock revetment that could be topped with a pedestrian promenade.

Bolton outlined trade‑offs: engineered structures such as seawalls or revetments can protect assets immediately behind them but tend to narrow beaches and create down‑coast sediment impacts; sand nourishment can restore beach width but is vulnerable to major storms; and relocation of assets is sometimes the only sustainable long‑term option for particularly exposed infrastructure.

Commissioners asked technical and policy questions. One commissioner asked whether the maps in the report were new; Bolton confirmed the team used higher‑resolution local modeling rather than statewide products previously relied on. When asked whether the city has a legal obligation to "keep" particular beaches, staff said there is no blanket legal duty to maintain any beach but legal duties arise when public services, health and safety or access to private property are implicated.

Bolton cited the cost of storm recovery as a driving factor for planning: "It's truly not sustainable for us as a city to spend $3,000,000 in cleanup and repair costs from a single large coastal storm like we did in 2023," he said, arguing that proactive planning provides a playbook for response and can improve permitting outcomes for future projects.

Funding and schedule: Bolton said the planning effort is funded in part by grants from the California Coastal Commission and the California Coastal Conservancy plus city funds. Staff said portions of the "quick wins" could be paid from existing waterfront budgets and that the consultant contract includes preliminary construction drawings for targeted core measures to accelerate permitting and funding steps. Outreach includes 12 boards and commissions, three open houses and targeted Spanish‑language engagement; the outreach phase closes June 4 at the Council Sustainability Committee. Staff anticipates a draft plan and implementation pathway in roughly one year and potential City Council consideration in late 2027.

The commission offered directional comments — including urging public education, attention to parking and commercial impacts, a plan for updating environmental data, and protections for significant historic resources along the corridor. Bolton said the plan will include an implementation pathway, funding strategy and recommended approach when the draft is released.

The commission took no action on the item; the presentation was for discussion and input.