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Government or official record

After the Devastation, a Safer Highway System

California Department of Transportation

Cross-File evidence ledger

Where this source supports the record

Each entry separates the File’s editorial relevance note from its exact, section-level claims. A bibliography link without a direct claim is labeled plainly.

  1. Engineering failures · 17 October 1989

    The Cypress Street Viaduct Collapse

    Cypress Street Viaduct collapse zone and memorial park · United States

    Open File evidence →
    Why editors use it here

    Caltrans account of the exact collapse extent, design and retrofit history, response, and later bridge-safety program.

    1. Quick read

      When the magnitude 6.9 Loma Prieta earthquake struck on 17 October 1989, a 0.7-mile section of Oakland's double-deck Cypress Street Viaduct collapsed.

      Reviewed 24 July 2026
    2. Trigger and conditions

      At 5:04 p.m., shaking from the Santa Cruz Mountains reached the Bay margins.

      Reviewed 24 July 2026
    3. Uncertainty

      Official sources sometimes report 41 rather than 42 Cypress deaths because of differences in attribution.

      Reviewed 24 July 2026
    4. Why it matters

      The failure was not produced by shaking alone.

      Reviewed 24 July 2026