HONOLULU -- The biggest, single tax increase in Hawaii's history is just one step away from final council approval. Two City Council committees Tuesday voted 5-to-2 to send the transit tax bill on to the full council for approval next week.

The proposal is to hike Oahu's excise tax 0.5 percent to pay for a new rail transit system

Mathematically, the hike turns out to be a 12.5 percent increase. That could mean up to $450 more in taxes a year for each family.

U.S. Rep. Neil Abercrombie told the council approve the tax hike or lose millions in federal funds.

"If you don't pass it... then everything is... well, that's the end of it," Abercrombie said.

Many in the packed room argued that the proposal is being pushed through too fast without adequate consideration of alternatives, such as a raised toll road.

"You get to speed home at 55 mph if you pay a toll and it has a little card. I think it is very possible to explore," said Dave Rolf, of the Hawaii Automobile Dealers.

"Nobody bothers to put those alternatives before the public. And the way Bill 40 is written, nothing but rail is considered in the bill," Waialua resident Jay McWilliams said.

Mayor Mufi Hannemann defended the plan after the committees approved the bill.

"I don't believe we are railroading this at all. We are committed to an alternative analysis that could take us as long as 18 months, where you can bring up every idea that you would like to see," he said.

The full council is expected to give final approval to the transit tax bill at a special meeting at Kapolei Hale on Aug. 10. The meeting is being held in Kapolei because Honolulu Hale will be under repair then.

The mayor said he hopes hundreds of Kapolei residents, residents who might use a transit system, will show up to support the measure.