Tiburon-funded living-shoreline project for Greenwood Beach moves toward construction after multi-source grants

Consultants and town staff told the Tiburon Parks, Open Space and Trails Commission on Dec. 16 that a living‑shoreline restoration project for Greenwood Beach and adjacent Blackie’s Pasture has advanced to final design, has secured construction funding and is on a path to go out to bid in spring 2025.

The project team has prepared plans and specifications for construction, completed environmental review in September 2024, and is responding to permit comments from regulatory agencies, consultant Roger Leventhal told the commission. Leventhal said the grant award covers completing 100% plans and specs, bidding and construction and that the team expects to finish plans and go to bid in May–June 2025 with construction starting, if permits and schedules hold, in September 2025.

Commissioners said the update matters because the shoreline at Greenwood Beach has been heavily eroded in recent years, exposing asphalt and concrete fragments and reducing usable sand. Leventhal said the design uses a combination of sand and gravel placement, replanting of native sueda (sea blite) and small drift‑sill features to retain sand and restore beach habitat rather than riprap. “We went with a much more design‑with‑nature approach,” Leventhal said.

Permitting, archaeology testing and contractor bidding are on the project’s critical path, the consultant said. He told the commission the team completed environmental review in September 2024 and has submitted permit applications; Bay Conservation and Development Commission (BCDC) comments have been the most extensive to date. The team plans to respond to BCDC this week and finish final plans in April 2025. Leventhal said a short, targeted archaeological survey (hand‑auger testing) along the slope is time‑critical for Army Corps and State Historic Preservation Office (SHPO) reviews and estimated that scope at about $25,000. “If for some reason significant resources are discovered, then we would have to modify the design,” he said.

Leventhal and staff described the work scope and schedule in greater detail: finish plans and specs in April 2025, go to bid in May–June, start construction in September 2025 and complete construction by fall 2025 or, in a slower scenario, during 2026. He said the grants are flexible through 2028 if construction slips. The team has applied for all permits and expects few deal‑breaking comments, but cautioned that permitting and archaeological findings remain schedule risks.

Commissioners asked practical questions about materials and staging. Commissioner Byrd asked what happens to eroding concrete and asphalt on the shore; Leventhal said the team will break up and reuse what they can and haul off material not suitable for reuse, with unusable pavement destined for landfill disposal. The team also described temporary construction closures and staging: beach areas where heavy equipment works will be fenced and closed during construction; parking and the main trail are expected to remain open.

Leventhal credited earlier grants and research for enabling the construction award: an initial grant and later San Francisco Estuary research work helped produce the living‑shoreline design. He said the project team secured a construction grant after persistence and outreach to conservancy staff and that the grant award was finalized at a November conservancy meeting. He identified funders and partners in general terms and thanked town staff for assistance in preparing the application and in negotiating the grant.

The commission requested the project team and staff continue to brief the commission as permit responses and the archaeology scope are completed, and to provide more detailed staging and neighbor‑notification plans before construction.

Provenance: first presentation remarks by Roger Leventhal begin at transcript block starting 477.535; last substantive design/schedule remarks end in the block at 1103.155.