If you ask Bellevue Mayor Grant Degginger, it is not the weather that will bring people to this economically viable region — it will be the capacity to move around.

At Tuesday’s membership meeting, the Bellevue Downtown Association (BDA) hosted a dialogue on the Sound Transit expansion plan headed to the ballot this November. Voters will decide whether to invest $17.8 billion in a new mass-transit project and service including a light-rail system connecting the Eastside and Seattle. During the debate, Seattle Mayor Greg Nickels stepped across city lines when he declared Proposition 1 a regional solution to a regional problem.

“This isn’t about Seattle or Bellevue or Redmond or Kirkland. This is about the Metro greater-Seattle, Puget Sound Region,” he said, and went on to say, “This is a good plan, it’s not a perfect plan and you’ll certainly hear some criticism here today, but it is a good plan.”

Bellevue Downtown Association President Leslie Lloyd opened the debate by introducing the panel brought together to share perspectives on the measure. The BDA Board of Directors supported the 2007 Roads and Transit package but has not taken a position on the current measure.

The debate was moderated by Essex Porter, a Kiro-TV political-affairs reporter and included a panel with representation on both sides of the issue. Nickels and Degginger represented the pro side and Washington Policy Center analyst Michael Ennis and Eastside Transportation Association (ETA) representative Dick Paylor sat on the opposing side.

Mayor Nickels kicked off the debate outlining the benefits of the rail plan to transportation. He claimed it would take about 150 buses to carry the equivalent amount of people that 15 trains would carry.

“At some point, downtown Seattle streets and downtown Bellevue streets along with highways will run out of room for those vehicles. The light rail and commuter rail will provide the heavy lifting for our cities and our region and that’s a legacy we can leave to future generations,” Nickels said, referring to it as a 100-year investment. “The capital cost is significant, that’s why we are going to the voters to make that initial investment.”

Opponents of Proposition 1 pointed to the rail-plan failure to provide transportation to the large population of people who live and work on the Eastside.

“Eighty-five percent of the people who start their commute trip in the morning end their trip on the Eastside,” explained Paylor of the ETA. “We need a transit that goes north to south into multiple places because not all the jobs are in downtown Bellevue.”

According to Paylor, the transit proposal on the table doesn’t address that.

The ETA finds it difficult to justify the $17.8 billion dollar price tag attached to the rail plan. Instead, the ETA promotes the idea of an Eastside bus-rapid-tranist system that would cost about $1 billion. The lines operated on high-occupancy lanes on Interstate 405 would not result in a high tax increase due to Sound Transit ability to cover the cost through existing taxes.

“Light rail simply doesn’t move that many people,” Ennis said. “These agencies come out and say the capacity for light rail (is) a million trips per day. Doesn’t matter. I have a brief case that can hold $1 million. Is there $1 million in there? No.”

Nickels explained that in 2030, which is seven years after this plan would be done, (light rail) will carry 360,000 people a day and will have a capacity of moving 24,000 passengers per hour.

There is plenty of concrete out there, he added, but the problem is commuters try to use it at the same time, from 6 to 9 in the morning and from 4 to 7 in the afternoon. During those hours, light rail will be carrying half the people in and out of downtown Seattle.

Mayor Degginger agreed with Nickels. He predicts that relying on a back-bone bus system would result in the same problem that currently inhabits the roadways — traffic and congestion.

“You would have to have a designated right-away and you have to build that infrastructure and there’s a high cost associated with that,” he said.

Either way, the region’s transportation system comes with a price tag, the question becomes how much are commuters willing to spend?

The cost of Proposition 1, according to Mass Transit Now, is about $69 per adult each year, roughly a 1 percent sales-tax increase.

If the measure passes, the agency promises to deliver light rail to Lynnwood and north Federal Way and from Seattle to Overlake all by 2023.

Paylor has his doubts. Looking back at Sound Transit’s history of cost overruns and delays, Paylor is worried these are promises that the agency will not see through.

In 1996, voters approved phase one, a $2.7 million billion rail line from downtown Seattle to Seattle-Tacoma International Airport. Mayor Nickels, who serves as Sound Transit chairman, said he remains proud of the progress and announced the rail line will open next year. However, the rail that was promised to reach Capitol Hill and the University of Washington will be finished a decade behind schedule.

Still, Nickels and Degginger stand firmly behind Proposition 1 for a new light-rail and commuter-rail system when looking toward the future of transportation.

Paylor was quick to point out that the future for commuters will most likely revolve around plug-in electric hybrid cars or other cleaner, less costly fuels.

“The goal is to move people at the end of the day. We can do more of that by continuing to invest in the bus system,” Paylor said.

On Nov. 2, citizens will be asked to decide whether to expand mass transit in the central Puget Sound region. For information on Proposition 1, visit www.soundtransit.org. For a better look at alternative solutions, visit www.masstransitnow.org.