The Polk County Board of Supervisors voted today to move forward with an estimated $40 million renovation of Veterans Memorial Auditorium in an effort to boost Des Moines’ convention business.

The plan calls for adding a ballroom and renovating the lobby on the west side of Vets and building a second level in the arena area that would house 14 meeting rooms and a junior ballroom.

This was one of two renovation options RDG Planning & Design presented at a meeting in March. The other called for spending about $30 million to add a second level to only half of the building.

The decision ends a long planning process to fulfill Economic Research Associates’ assessment in 2008 that called for adding 60,000 square feet of ballroom and breakout space to the Iowa Events Center. The revamped auditorium will replace the Polk County Convention Complex, which needs up to $20 million in renovations, and could save facility manager Global Spectrum about $500,000 a year in operating the Events Center.

To fund the expansion, Polk County would refinance its debt on the entire complex and extend payments by another few years.

Supervisors overwhelmingly expressed approval for the project, citing the need to remain competitive in the convention business as nearby cities expand or renovate their convention space. It also will provide jobs during the recession, they said.

Tom Hockensmith said he supported the project after seeing the success of the Events Center, which went from a deficit when it opened to a $350,000 surplus in the past fiscal year.

E.J. Giovannetti said his only concern was the timing of the project, but “I think if we wait too much longer, it might put us behind the eight ball in terms of our competitiveness,” he said.

“We have to be competitive,” said Robert Brownell, “and this would do that.”

This morning’s vote will allow the county administrator to issue requests for proposals for architectural and other services necessary to move forward with the plan, which County Administrator Ron Olson expects will be ready in the next week to 10 days.

“This does not create a blanket approval,” Olson said. “It approves taking the first step toward accomplishing this project.”