MOLINE, Ill. — The moment blowing up the eastbound tower of the old I-74 bridge took months of planning and expert engineering. Keeping the public and wildlife safe was one priority, and getting the controlled explosives to detonate on-time, was no easy task.
"It went perfectly," said Iowa DOT Senior Project Manager Ahmad Abu Afifeh. "It was the best outcome we could have hoped for."
Each step was meticulously prepared.
"There was blast charges for critical locations and timed within microseconds of each other," Abu Afifeh said. "This way they would rupture at critical sections that we hoped for and at the critical time that we want. This way it could guide the bridge toward the direction that it fell."
The two towers fell towards the outside of the river channel to minimize disruption of the side channels.
Diving crews and contractors removed the debris from the river with cranes. Once the large pieces of the bridge are taken out, a final LIDAR scanning will be conducted to ensure all debris is collected. That debris will then be taken to a demolishing yard.
"Very few times you see a bridge being demolished through blasting," Abu Afifeh explained. "But typically those longer bridges with suspension cables, that is this is the safest way to blast it."
Iowa DOT says it can only blow up one part of the bridge at a time for safety reasons. The organization plans to remove the other half of the bridge in the coming months.
"We're hoping the second blast goes as well as this one," Abu Afifeh proclaimed.