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Schoharie Creek Bridge
Co l l apse Inves t i gat i on
On April 5, 1987, two spans of the five-span Schoharie Creek Bridge on the New York State Thruway plunged into the flood-swollen creek; about
ninety minutes later, a third span collapsed into the water. Within hours, the New York State Thruway Authority retainedWJE to launch an exhaustive
investigation into the cause of failure of this thirty-one-year-old structure.
The investigation of the collapse of the Schoharie Creek Bridge focused attention upon the potentially catastrophic consequences of scouring
around bridge supports. It triggered an increased level of awareness and monitoring of scour by state transportation departments across the
country. The project also confirmed WJE’s reputation as a bridge expert and enhanced its reputation as a firm with the ability to respond quickly
to catastrophic failures.
Notes of Interest
• Although the Schoharie Creek Bridge had been
inspected annually or biennially since 1968, an underwate
inspection of the pier footings had never been performed.
The bridge was scheduled for an underwater inspection in
1987, but the bridge collapsed before the inspection
took place.
• TheWJE report noted that bridges must be designed for
hydraulic, geotechnical, and structural effects. Of the three,
only the geotechnical design, relying on the support
strength of the glacial till, was satisfactory.
• Due to the collapse of the Schoharie Creek Bridge and
other bridges failing in a similar manner, bridge inspectors
were further trained to recognize scour potential by
examining and comparing any changes in the conditions
from previous inspections. Scouring failures also sparked
much-needed research for detecting scour potential.
WJE 50 Years