Wichita ? Wichita voters will get to decide whether the city should build a $150 million downtown arena.

The city council on Tuesday voted to put the question before voters May 21.

If approved, the plan would increase the city sales tax a half-cent to 6.4 percent for 13 years to pay for the 17,000-seat arena.

But the increase also would pay for rebates for car buyers, something several speakers at Tuesday’s meeting opposed.

Council members received the final details of the plan less than a day before the vote. Some at the meeting, including former state Rep. Henry Helgerson, said council members should have delayed voting to give themselves and residents more time to study the proposal.

But council members said they believed the only issue before them was whether to allow the public to decide the fate of the arena proposal, which was developed by the Greater Wichita Area Sports Commission. The commission will pay for the election.

“It’s not up to us to fine-tune the issue so that it will pass or fail,” Councilman Bob Martz said after the vote.

Arena campaign leader George Fahnestock told council members the arena would turn a run-down industrial zone at the city’s core into a vibrant commercial area that would complement other public improvements such as Old Town, Exploration Place and the Arkansas River corridor.

Fahnestock touted the sports commission’s estimates that the arena would generate more than $660 million in construction and consumer spending over 10 years, along with about $150 million of sales and property tax income for local government.

The sales tax increase is expected to generate about $637 million and could not be extended without another vote of the public.

Under the plan, senior citizens could file for a rebate to offset the half-cent tax increase, but would not be eligible for the car buyers’ rebate.

The 1.5 percent rebate for car buyers effectively would lower the sales tax on cars bought in Wichita to 4.9 percent.

Car purchasers would receive relief not only on the half-cent increase, but an additional one-cent rollback of the existing countywide sales tax. That part of the plan lengthened the period of the arena tax from nine to 13 years.

The tax rebate was added to the proposal after the Wichita Auto Dealers Assn. announced that it would oppose the arena. The group has since reversed its decision and now supports the plan.