The Big Slide is today

The Big Slide is today, and instead of being in Madison, Ind., or Milton, Ky., I'm stuck here in West Virginia trying to earn enough money to make my next car payment. Here's what the folks at the Milton-Madison Bridge Project e-mailed out yesterday. Text and photos are taken directly from the e-mail. Enjoy.

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It’s the largest bridge slide of its type in North America. The new Milton-Madison Bridge, which spans nearly a half-mile and weighs some 30 million pounds, will slide 55 feet laterally from its temporary piers and onto refurbished permanent piers.  


The slide, scheduled to begin Wednesday morning, April 9, could take up to 16 hours before the bridge rests in its final location – on top of the refurbished piers that held the old Milton-Madison Bridge in place beginning in 1929. The Coast Guard will close the river during the slide.

“We’re making history in Indiana and Kentucky,” said Karl Browning, commissioner of the Indiana Department of Transportation. “Through hard work and creative engineering, we’ve been able to rebuild this bridge quickly and cost effectively.”

Pulling a half-mile structure weighing 30 million pounds a distance of 55 feet in a matter of hours is an engineering marvel, though simple in concept.

Polished steel sliding plates are secured on top of the refurbished piers. Steel cables and hydraulic jacks controlled by computers will be used to pull the bridge. A total of eight jacks are mounted on the piers. Industrial lubrication is put on the sliding plates to grease the skids. Then, through a series of grabs and pulls, the bridge is slid into place. Each grab and pull is expected to move the bridge 20–22 inches – up to 10 feet per hour.

Once the bridge is in its final position, additional work has to be completed before it can reopen, including inspections, welding and bolting it in place, reconnecting the driving surfaces, installing expansion joints, pouring concrete, configuring drainage and re-striping.

“Everyone is a winner on this project,” said Mike Hancock, secretary of the Kentucky Transportation Cabinet. “We’re showing the rest of the country how two states, by strategically working together, can deal with aging infrastructure in creative ways that improve safety and better the quality of life for their citizens.”

All schedules are tentative because weather and other factors can alter the schedule. If all goes as planned, the bridge will reopen to traffic about a week after the slide.


The new steel truss bridge is 2,428 feet long and 40 feet wide with two 12-foot lanes and 8-foot shoulders – twice as wide as the old bridge. A 5-foot-wide cantilevered sidewalk will be added to the structure in the coming months after the slide.

The Milton-Madison Bridge Project – a joint effort between the Indiana Department of Transportation and the Kentucky Transportation Cabinet – has received numerous awards. It was named one of the top 10 bridge projects in the country by Roads & Bridges magazine, received a 2012 Best of What’s New Award from Popular Science magazine and received several state and national engineering awards for innovation. For more information, visit http://www.MiltonMadisonBridge.com or follow the project on Twitter.