OREGONIA, Ohio -- An hours-long closure of Interstate 71 dragged on longer than expected, as crews worked to demolish the last of the old Jeremiah Morrow Bridge.
The span, which stood since 1964, wasn't going quietly.
Technicians blasted the southbound span's remaining steel trusses shortly after 7 a.m. However, one section remained standing, and another section only partially collapsed.
Watch the blast up close (video courtesy Ohio Department of Transportation):
An aerial view from Chopper 9 gives some perspective on what happened:
A second attempt, at about 11:45 a.m., appeared to be a success.
I-71, closed through the demolition site, reopened just after 1 p.m. -- two hours later than planned. Traffic was detoured through Warren County for eight hours, along state routes and a U.S. highway.
What went wrong?
A connection to one of the blast charges came loose during the initial implosion, Ohio Department of Transportation spokesman Matt Bruning said. They're wired similar to Christmas lights, so one faulty connection stops the entire sequence.
"You have to expect the unexpected, you know?" Bruning said. "Certainly anything can go any way."
Crews had to check the connections to find which was loose. Two workers dangling from a crane did at least some of that checking.
To save time, two detonations went off together -- to bring down the still-standing section and to completely collapse the partially standing section. But, that partially standing section remained upright even after a second blast. Bruning said ODOT would use other methods to bring it down.
What about I-71?
A detour was in place between state Route 73 and state Route 48 throughout the morning. On I-71, the traffic backup was miles long.
Before the freeway could reopen, inspectors needed time to check the adjacent, new span to be sure it didn't sustain any damage, Bruning said.
The old bridge's pilings will be taken down manually during the summer.
The new bridge opened last November. Construction of the $88.1 million bridge took six years. It is the tallest bridge in Ohio and designed to last 100 years, officials previously said.