The Grayson  PrestonIowa Department of Transportation used controlled explosives Sunday to remove the remaining parts of the old I-74 bridge, which connects Iowa and Illinois over the Mississippi River.

Certain areas were temporarily closed, including the new bridge, during the removal of suspension cables and towers on the old bridge, the Iowa DOT said on its website. 

“The main navigation channel in the river will be closed to all river traffic for up to 24 hours,” the Iowa DOT said.

In June, the Iowa DOT removed parts of the old I-74 bridge in the first phase of the demolition. The new bridge was built because of “increased traffic volume” the Iowa DOT said.

I-74 bridge demolition, explosion video

How old is the bridge?

The westbound bridge, Illinois to Iowa, opened in 1935. The eastbound bridge, Iowa to Illinois, opened in 1960.

How much did the new I-74 bridge cost?

The new bridge was built in July 2017 and was fully opened in December 2021.

The project cost about $1 billion in total, including engineering, design and construction costs.