Spectators in downtown Des Moines were treated to a rare sight Nov. 17 when two new cooling towers were airlifted via helicopter to the top of the 36-story Ruan Center.  

A helicopter provided by CHI Aviation of Howell, MI, was contracted by Baker Group to lift the two towers. Each cooling tower weighed about 11,000 pounds and had lower and upper sections that were lifted separately and stacked on the roof.  The entire aerial lifting process took about 45 minutes.   

IMEG provided mechanical, electrical, and structural design for the cooling tower replacement project. After the new towers are connected to the existing piping and put into operation, the two existing cooling towers will be disconnected and removed. Two additional new cooling towers will be lifted to the roof of the building in January.   

According to local news outlets, this is the first time a helicopter lift like this has been done in downtown Des Moines. 

Watch a video of one of the cooling towers being lifted.