MORROW, Ohio - It's hard to see much of the new Jeremiah Morrow bridge going over the Little Miami River on Interstate 71.
But the construction happening below the road is nothing short of amazing.
"It's a once in a career type project," said ODOT spokesperson Dan Mendel.
The Jeremiah Morrow isn't just any bridge. At 240 feet above the Little Miami River, it's the tallest bridge in the state of Ohio.
"There's a lot of what we call 'cookie cutter' bridges," said Michael Swan, Project Superintendent for Omnipro Services, which is managing the construction. "Very rarely do you get to build something as unique as this."
Because of the terrain and the need to have the new span sprout between the old north and southbound bridges, the Ohio Department of Transportation decided on a plan of action almost unheard of in the Buckeye State.
It's called a balanced cantilever bridge.
Emphasis should be given to the word 'balance.'
The workers start with a pier, or concrete support column, rising up as much as 80 yards from the canyon floor to the level of the roadway. Then they begin building out toward the next pier, foot by foot with concrete-with no external support.
"Carefully poured, each section, one side at a time, trying to keep the entire structure as close to in balance as possible," said Swan.
Like a man on a tightrope holding a balancing pole that just keeps getting longer. Machines called form travelers inch out over the abyss. They place forms for the concrete sections that will eventually join over the river.
Inside the growing span, a cavity big enough to drive a Greyhound bus. Workers move the inner frameworks ever outward, as more concrete is poured. Steel cables called tendons are threaded through the segments keeping the concrete from collapsing of its own weight.
"This is different, for sure," said journeyman carpenter Fred Newland, who hasn't seen anything like this in his career.
He tries to explain it to his friends, with little luck.
"I tell 'em about where I'm workin' at, what I'm doin,' and how cool it is," he said. "I don't think they can comprehend."
The new bridge is designed to last 100 years.
Because concrete doesn't need to be painted, builders say it will save taxpayers millions in maintenance costs.
Drivers should have a much quieter crossing than with the old bridge.
"It will definitely be a smoother ride," said Dan Schweiger with Kokosing Construction. "It won't be as bouncy."
ODOT plans to have the bridge open in summer of 2016.
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