At Blackbird Investments, it’s in with one swimming pool and out with another.

The Des Moines development firm recently caught many headlines by proposing a swimming pool cantilevered off the 26th and top floor of a residential high-rise at the site of the former Younker’s building downtown. The pool is one of many unique features planned for what is called 701 Walnut, an $85 million project that is being designed with many wow factors in mind.

Just a few blocks away at 10th and Mulberry streets, Blackbird is rehabbing the Clemens Building, a 100-year-old structure that once was appended to the Hotel Fort Des Moines and at the moment is known as the home of Bubba’s restaurant.

Blackbird bought the property in August 2015 from Jeff Hunter, who sold both the Clemens Building and the Hotel Fort Des Moines that year.

Back in 1983, Hunter decided the hotel needed a swimming pool and he had one built on the sixth and top floor of the Clemens building. As it turned out, the 1,200-square-foot pool was designed with some wow factors in mind.

“The one memory that leaps to mind dates to 1986 just after the pool was finished,” Hunter said in an email. “The architects must have made a submittal somewhere and the design won a regional award from Interiors magazine. I even flew to New York to accept the award and brought home the modest plaque that marked the win in the ‘Minnesota’ design category. My fellow Minnesota designers at the ceremony made note that there apparently was no Iowa design category and this was the closest thing. My how times have changed for Des Moines and the rest of Iowa.”

Blackbird partner TJ Jacobs said that as part of the $13 million redevelopment of the Clemens Building, the partners planned to remove the pool. The partners anticipated a plastic pool and a quick removal. What they encountered was thick concrete, steel reinforcing and a job that took longer than expected, Jacobs said.

“It was kind of a wild idea to put a pool on the top level,” he said. We didn’t realize it would be concrete. It probably was as stout of a pool as you could possibly put in. … It was a hulk.”

Blackbird has elaborate plans for the floor, which once also provided a connection to the Hotel Fort Des Moines.

Eight of the building’s 44 apartments will be located on the sixth floor. Four of the apartments will be two stories with exclusive rooftop access. The other four will share access to a community room and event space, also on the roof.

Apartments will push $2 per square foot, a level that is at the upper end of the downtown market.