Port and Army Corps unveil $13 billion draft waterfront flood study; NEPA and Section 106 comment period open through March 29

Port and Planning staff briefed the San Francisco Historic Preservation Commission on Feb. 7 about the San Francisco Coastal Waterfront Flood Study, a multi-decade feasibility analysis led by the U.S. Army Corps of Engineers in partnership with the Port of San Francisco. The informational presentation opened a 60-day NEPA public comment period that runs through March 29, 2024.

Danielle Ng Oh, senior planner in the Planning Department's citywide division, introduced the briefing and said comments submitted at today's hearing and the March 20 session will be combined into a comment letter from the commission to the Army Corps.

Adam Barrett, planning lead for the Port's waterfront resilience program and the flood study, said the draft plan assesses coastal flood risk and sea-level rise through the year 2140 and includes a preliminary, high-level cost estimate of about $13,000,000,000. Barrett said that if the recommended plan is authorized by Congress, the federal government would fund roughly 65% of the construction cost, with the remainder expected from state, local and other sources. Barrett emphasized the estimate is preliminary and subject to change.

The draft study divides the long waterfront into four reaches and proposes different approaches by reach: lighter-touch floodproofing and short flood walls in Fisherman's Wharf; higher, one-time shoreline elevations and raised wharves along portions of the Embarcadero (designed to defend against up to about 3.5 feet of sea-level rise in that reach); berms, levees and closure structures in South Beach/Mission Bay; and berms, nature-based features and short walls in the Southern Waterfront/Bayview areas. Barrett said the study also models long-term economic exposure: the draft notes up to roughly $23,000,000,000 in potential economic damages by late-century under high-rise scenarios.

Kelly Capone, flood study project manager and environmental lead, explained the NEPA public-comment process and the parallel Section 106 (National Historic Preservation Act) programmatic-agreement negotiations. Capone said a draft programmatic agreement is available for comment within the NEPA comment period and that the Section 106 process will continue in parallel, allowing consulting-party status and iterative revisions.

Commissioners pressed staff on coordination across jurisdictions (including the National Park Service and other agencies), the adequacy of a 60-day NEPA comment window for a project of this scale, phasing and when project-level design and construction might begin. Barrett said the project team will develop a phasing plan over the next year and estimated that, if authorized and funded, detailed design could take 5 10 years with construction phased across decades (implementation could begin in the 2030s for early phases). Jeremy Shaw (Planning Department staff) and Barrett described existing City guidance on sea-level-rise assumptions and said those assumptions are updated as science evolves.

A member of the public, Patricia Richardson, urged the team to consider toxic-waste risks, endangered species, insurance impacts on homeowners and potential immediate funding opportunities.

Barrett closed by noting early projects (separate from this Corps-led study) are already underway, financed in part by the 2018 Proposition A Embarcadero Seawall bond, and that the draft plan will be refined based on public and agency comment. The commission will revisit the study on March 20 for NEPA, Section 106 and programmatic-agreement discussion.

Sources: Presentation and Q&A by Adam Barrett, Kelly Capone and Port/Planning staff to Historic Preservation Commission, Feb. 7, 2024.