Commission reviews Islais Creek Bridge alternatives, staff says replacement will cause unavoidable historic impacts

Planning staff presented preservation alternatives for the Islais Creek (Levon Hagop Nishkian) Bridge and told the Historic Preservation Commission the proposed project—demolishing the existing bascule bridge and replacing it with a higher, fixed single‑span concrete through‑girder bridge—would result in a significant and unavoidable impact to the historic resource under CEQA.

Staff outlined the bridge’s historic significance (completed 1950, Art Moderne features, previously determined individually eligible for the National Register) and noted the National Bridge Inventory structural rating of 20 out of 100 with a structural note of 0. Project objectives include raising the deck to address sea‑level rise, correcting seismic deficiencies, improving Muni serviceability, minimizing construction time, and accommodating bicycle and pedestrian facilities.

As possible mitigation, staff described a preservation alternative that would salvage or replicate above‑deck character‑defining elements (bascule girder housings, rivet‑like patterns using form liners, guardrail replication) and retain the control tower where feasible, while converting to a fixed span. Staff said maintaining drawbridge functionality would not be feasible while meeting most project objectives, and that rehabilitation options from prior projects did not meet current sea‑level or Muni operation goals.

Commissioners pressed staff on feasibility, the relationship between raising the bridge and broader regional sea‑level‑rise adaptation, and the need for interpretive elements if character features are replicated. Several commissioners emphasized equity and transportation access concerns for Bayview and Hunters Point residents. Project staff said inputs from charrettes and prior studies informed the proposal and pledged to document the commission’s recommendations for the draft EIR. The item was reviewed for comment and will return during the draft EIR process; no formal commission action was required at this hearing.