PennDOT cameras caught a second blast about 24 hours after crews imploded Pittsburgh's Commercial Street bridge when cleanup equipment struck an unexploded stick of dynamite. No injuries or equipment damage were reported, and crews re-swept the site and received an all-clear roughly 12 hours later. PennDOT described the event as an isolated mistake and said it will not pursue further contractor investigation.
Leftover Dynamite Detonates During Pittsburgh Bridge Cleanup — Cameras Capture Second Blast
Image Credit: CBS News Pittsburgh / YouTube.
Pennsylvania Department of Transportation (PennDOT) construction cameras recorded a surprise second explosion about 24 hours after crews imploded the old Commercial Street bridge as part of the Parkway East renovation. The footage shows a sudden plume of dust and workers scattering when an equipment operator struck an unexploded stick of dynamite while clearing debris from the demolition site.
What Happened
The implosion reopened the Parkway East a full week ahead of schedule, but cleanup continued the following morning. At roughly 7:40 a.m. on the 17th, PennDOT cameras captured a short-lived detonation as crews sifted through rubble left from the controlled collapse. District 11 Senior Assistant Construction Manager John Meyler told KDKA that an operator hit what he described as an unknown, unexploded stick of dynamite and it detonated on impact.
Response and Safety
Fortunately, no one was injured and no heavy equipment was reported damaged. Crews had already conducted an initial sweep after the implosion and cleared the site, but Friday's blast prompted an immediate, more thorough recheck of the area. About 12 hours after the secondary detonation, crews received another all-clear and resumed work.
PennDOT indicated it does not plan to pursue further investigation of the demolition contractor, describing the incident as an errant mistake in the process, according to Meyler. Local reporting from CBS News Pittsburgh confirmed that the item involved was a single stick of dynamite that had not detonated with the rest of the charges.
Why This Can Happen
Controlled implosions use multiple charges fired in sequence; a faulty connection, a slightly damp charge, or an isolated misfire can leave ordnance intact. While uncommon, unexploded charges are a known risk in the demolition industry, which is why protocols require multiple sweeps and careful post-collapse inspections before crews and equipment fully re-enter a site.
Bottom line: This was a rare but contained incident in which safety procedures and a rapid response prevented injuries or equipment damage, underscoring the careful follow-up work required after large-scale demolitions.
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