By Jack Dura, AP

A nearly 100-year-old bridge over the Mississippi River between Iowa and Wisconsin was imploded on Dec. 19, an unusual spectacle that clears the way for a modern replacement.

The Mississippi River Bridge, also known as the Black Hawk Bridge, was completed in 1931. It connects Lansing, Iowa, to Wisconsin. The landmark stood out for its unique cantilever design — a center arch and two towerlike trusses.

People gathered near the snow-covered riverbank under a sunny sky and cheered when explosives fired off. Black smoke and white spray flew up as the center span and a truss dropped into the water below. The spans rested half-submerged in the river.

Lansing Mayor Michael Verdon, who watched the demolition from a houseboat dock, called it “pretty bittersweet, actually.”

“Every time I looked at the river, I saw that bridge profile in the horizon,” the Lansing native said. “On a personal level, it’s sad to see that it’s gone.”

The bridge, which closed in October, was the only one for about 30 miles in each direction and carried about 2,100 vehicles per day, according to the Iowa transportation department. Drivers can use a ferry service while a new crossing is under construction. The planned $140 million replacement is expected to be in service in 2027.

Though it was beloved, the narrow bridge made for a harrowing experience when two large trucks met, Verdon said. Barges sometimes struck the bridge because of the river geography and configuration of the bridge piers.

Another implosion, for the bridge’s eastern ramp, was set to follow the main event later on Dec. 19, the mayor said. Officials plan to disassemble the bridge’s western section in the future because parts of it extend over homes and the railroad.

Some parts of the bridge had already been removed, but an implosion was the most efficient way to remove the largest portions of the superstructure, Iowa Department of Transportation spokesperson Daniel Yeh said.

Residents plan to salvage material for keepsakes and to construct a tribute to the bridge in the city, Verdon said.

Lansing, population 968, has deep roots as a river town with a history of steamboats, fur trading and commercial fishing, the mayor said.

Dura reported from Bismarck, North Dakota.