Examining local bridges after Florida tragedy

Another lawsuit was filed this week in the wake of a pedestrian bridge collapse in Florida that killed six people. Similar bridges have been built in Iowa in recent years, but experts say they are perfectly safe.

The bridge collapse in Florida put a spotlight on the technique used to build bridges faster called ABC, which stands for Accelerated Bridge Construction.

It's a way to minimize traffic disruptions and maximize safety. A bridge that was replaced using the ABC technique, and there are hundreds of them, doesn't mean it was built the same as the one in Florida.

ABC actually refers to dozens of different accelerated construction methods.

For example, in 2011 the Iowa DOT hailed the bridge replacement just outside of Council Bluffs on Highway 6 over Keg Creek as a first in the state.

The bridge deck was built out of the way and off to the side and the parts put in place like a jigsaw puzzle. The highway was closed for just 9 days.

Another bridge in Massena, Iowa became a good candidate for innovative bridge construction because every the bridge would have been closed, the detour would go for 13 miles. 7 miles of it was out of the way.

Chase Wheatley is from Massena and knows what that's worth.

"The whole thing went a lot smoother than shutting down the bridge for long periods of time."

This ABC technique is called the lateral slide-in method. Iowa DOT crews built the bridge deck off to the side while Highway 92 remained open.

Once everything was ready, crews destroyed the old bridge and using a jacking system the new bridge was slid into place. Instead of Highway 92 being closed near Massena for the summer of 2013, it was closed for just 14 days.

Wheatley feels secure that the bridge is safe.

"There's been a lot of big equipment going across it. It's been pretty well tested."

An engineer with the Iowa DOT says the public doesn't have anything to worry about with its ABC bridges since they're so different from the Florida one.

The Nebraska DOT says that there are no bridges in Nebraska built using the slide-in method or the self propelled modular transport method used in Florida. Investigators are still working to determine exactly what caused that bridge to collapse.