Demolition of former Kaleidoscope at the Hub in Des Moines underway for skyscraper project

Demolition of the former Kaleidoscope at the Hub building is underway to make way for a long-anticipated high-rise apartment tower in downtown Des Moines.

Over the next 50 days, crews will dismantle the building at 515 Walnut St., leaving behind sunken dirt mounds. The demolition is the first step in a long-awaited $140 million skyscraper project that could come after years of uncertainty over the fate of the former Kaleidoscope at the Hub.

What's the plan for the downtown skyscraper?

The spot could become the tallest living space between Denver and Chicago, which would consist of 390 multi-family apartment units and 1,400 square feet of commercial space on the first floor, according to developer Joe Teeling, of St. Joseph Group. It's expected to be 33 stories tall, which would make it the third tallest building in Iowa behind 801 Grand and Ruan Center.

The glass tower would have a coffee shop, bike storage and a dog park on the first floor. The second floor would have a shared workspace, conference room, fitness room and yoga studio. On the top floor would be gaming and dining lounges, with a deck on the roof.

More: Who's behind the new Des Moines skyscraper plans? Is Blackbird involved again? What we know:

What will happen with demolition?

The building's interior, once home to the vacant Kaleidoscope mall and food court, already is fully gutted, said Andy Beal, co-owner of Beal Derkenne Construction.

The crew started demolition on the exterior Tuesday. Over the next several weeks, workers will sever the skywalk connections before they start tearing down the building, Beal said.

Crews will use power tools to disconnect the skywalk on the south and east sides of the building. A small L-shaped section of the building and the skywalk connections on the west and north will stay standing, but will remain closed to the public, he said.

When skywalk demo is wrapped up, the team will use excavators weighing up to 80,000 pounds to sheer through the steel structure section-by-section, Beal said. He compares the tools to an oversized set of scissors attached to an excavator. From there, building materials will be sorted into piles and hauled off the site in dump trucks.

The plan is to clear the 0.86-acre site on Walnut Street between Fifth and Sixth avenues. The proposed tower would be built on 0.35-acre plot on the eastern half of the block, leaving the western balance of the property open for future development.

More: A downtown Des Moines skyscraper already failed once. Will the city's protections pay off?

Beal said the biggest challenge will be hauling large equipment on and off site in a "tight" downtown area that's "flanked by other large buildings and busy streets." But after the project failed to materialize under former developer Blackbird Investments, Beal said the opportunity to reengage the plans is an "achievement."

"It's a major milestone, he said. "We sat here four-plus years ago, dreaming this would happen."

How will demolition impact traffic in downtown Des Moines?

Walnut Street between Fifth and Sixth streets will remain closed indefinitely until demolition is complete.

The barriers will be removed, however, during RAGBRAI as riders make their way west on Walnut Street to Water Works Park on July 26 and back east on July 27 on their way out of the metro and to Tama-Toledo.

When will construction start on the skyscraper?

The whole demolition process could be completed by the beginning of September.

Depending on financing, construction on the skyscraper could start as soon as the fall. Teeling said in April he had 18 investors and a commitment on 85% of the bonds needed to finance the project.

Teeling has said the tower could open in 2025.

What will happen if the tower doesn't get built?

Des Moines and the development team have an agreement that spells out how to get the skywalks linked back up should the tower not be built. The team has three years to reestablish skywalk connections after they are severed.

• It will be the developer's responsibility to relink the skywalk connections.

• If the developers fail to rebuild, the city has $1 million in escrow to make the repairs.

• The city has permission to access the property in order to carry out the reconstruction.

• If repairs cost more than $1 million, the city has the right to assess the property so that if the site is eventually sold, the city will be repaid.

Virginia Barreda is the Des Moines city government reporter for the Register. She can be reached at vbarreda@dmreg.com. Follow her on Twitter at @vbarreda2

This article originally appeared on Des Moines Register: Kaleidoscope at the Hub demo begins for new Des Moines skyscraper