Man: Five, four, three, two, one.

Fire in the hole.

Fire in the hole.

Nebbe: That was Lansing's Black Hawk Bridge, and if you're only interested in explosions, you could stop here, but to do Lansing and the bridge justice, this story needs to start decades earlier.

♪♪ Long before its implosion, amidst the idyllic expanse of Northeast Iowa's Driftless Region, one long-standing staple was Lansing's Black Hawk Bridge.

Surrounded by beautiful mounds of earth, the sharp lines and geometric shapes of the bridge mark an abrupt shift in the region's topography.

While it has served travelers for decades, this type of bridge is actually quite antiquated, and specifically for the Black Hawk, its days are numbered.

Burke: It's incredibly rare in modern days to build another truss bridge like this.

The railroads do truss bridges still quite often, but we don't do these on the highway system anymore.

Nebbe: Originally opened in 1931 as a privately owned toll bridge, in 1957, the state took over the Black Hawk Bridge and rehabilitated it to comply with federal safety standards.

In its nearly 100-year lifespan, Black Hawk has become the icon of Lansing, with its likeness replicated all over town.

Burke: So I grew up right here in Northeast Iowa.

I have a lot of memories of the bridge here.

It's really an identity for the local community.

It's a core piece of infrastructure.

It gets people across the river to their jobs, their livelihoods, family, loved ones, so it's really a very important core piece of the local communities here.

Nebbe: But now, after 90 years, Lansing will have to identify with a new bridge, as the Black Hawk's time in service is coming to a close.

Burke: Unfortunately, all bridges have a lifespan.

That lifespan is typically around 100 years for modern bridges, and it's pretty impressive that this bridge, built in 1931, has lasted to this point.

After they're built, they immediately start to decay.

They rust.

The concrete starts to develop cracks.

And a bridge just gets more expensive to repair and to upkeep.

And in this case, we are looking to replace it with a bridge that doesn't have the same maintenance costs and a bridge that has modern safety features.

Nebbe: As the original Black Hawk is being dismantled and prepared for removal, simultaneously, the new bridge is being constructed.

While the project first had the community up in arms, it is now being watched closely, with its 2027 completion eagerly anticipated.

Burke: The first thing we proposed was an arch bridge.

It would not match anything in the community.

It wouldn't really feel like a good fit.

So there was a lot of resistance at first, and then we kept working through the public involvement process, and eventually we came up with a truss design that looked very similar to the existing bridge.

And after we presented that to the community and said, "This is an option that we can provide," the community started to relax and said, okay, this could be the next Black Hawk Bridge.

Nebbe: With a new bridge plan in place, the next step was removing the old bridge.

As careful measures were taken to dismantle sections of the Black Hawk, to make quick work of the truss span, there was really only one choice.

The project is coming up on the actual implosion of the existing structure.

There's a lot of excitement going on around town, as this is really a once-in-a-lifetime event.

If you see those boxes back there, there are explosives lining the bridge.

And then tomorrow, around 9:00 or 10:00 a.m., they will set off those explosives, and the truss will drop in the water.

Nebbe: "Excitement" is putting it mildly.

People drove in from counties away.

A raffle was held to push the ceremonial detonation button.

Local businesses held watch parties.

And with last-minute safety checks and crowds lining the river, we return to where this story began.

Man: Two, one.

Fire in the hole.

Fire in the hole.

♪♪ ♪♪ ♪♪ ♪♪ [ Crowd cheering ] Nebbe: Now the real work begins.

With over a year remaining in the construction of the new Black Hawk Bridge, when it opens for traffic, travelers will find it twice as wide, the structure 15 feet taller, and it will have a wider river channel for water traffic.

So Lansing isn't so much losing a piece of its history, as it is upgrading.

We used to cross that all the time to go up to La Crosse, go see monster-truck shows for my birthday.

I was really excited to be able to work on a cantilever through truss design, and I hope the entire community is very proud of the new structure that we build, that it still becomes a core component of the communities.