The latest projections show that by 2030 a rail transit line could ease traffic congestion by 10 percent overall — as much as the school summer break now helps the morning commute — city transportation officials said yesterday.

By then, however, traffic congestion will likely worsen since 30 percent more people are projected to be on the island. And the situation would be even worse without transit improvements, said Toru Hamayasu, chief planner in the city's transportation services department.

"Otherwise, there's no sense doing this," he said.

Other projections released yesterday by city officials and transit consultant Parsons Brinckerhoff Quade & Douglas show that the biggest increase in public transit ridership — bus and rail — would come from a fixed guideway or rail system. Three other options also are being considered.

Ridership projections show an estimated 305,000 people using public transit daily by 2030 with rail as part of the mix. That's more than 70,000 riders above the dedicated lane and bus options, said Mark Scheibe, project manager for Parsons Brinckerhoff. That compares with an estimated 180,000 who use public transit today and a projected 235,000 daily bus riders if no action is taken.

The city and Parsons Brinckerhoff are taking the latest information across the island in a series of community meetings starting Monday. (See schedule in box).

They're also crunching numbers trying to determine the best transit system they can propose that will still come in at about the $3 billion price tag that Mayor Mufi Hannemann has put forth as a goal. In addition to rail, expanding the bus service and systems that manage highway lanes are under consideration.

Last night, about 100 people turned out for a Mo'ili'ili community meeting sponsored by lawmakers to hear details of the plan, ask questions and voice their concerns.

"I'm for rail, as long as they keep it affordable," said Manoa resident Jim Quimby. "The costs are high, but I believe it's necessary. I'm more for it now than I was a month ago."

Others, however, were not so supportive.

"People will never get out of their cars for this. We need to build more super highways," said Ray Gruntz, a member of the Waikiki Neighborhood Board, which voted to oppose a rail spur to Waikiki. "I'd pay a toll to use a highway."

LOOKING FOR TRADE-OFFS

The city expects to provide the City Council with cost and ridership estimates for the "basic no-frills system" that Hannemann backs, though officials still will come up with a plan and cost for the original proposed 26-mile, Kapolei-to-University of Hawai'i-Manoa route as well.

Hamayasu estimated the shorter route still will cover 15 to 20 miles.

"It's not a short segment; it's a pretty substantial system that covers service to many communities," he said.

Some had proposed running the shorter segment from Leeward Community College to downtown, but Hamayasu said the city also is looking at other trade-offs. He said they could rule out the more expensive proposals to go underground in downtown to be able to pay for a longer route.

With growth targeted for the Leeward area, planners would like to get as close to Kapolei as they can. "We're trying to reach as far west as possible," Hamayasu said.

PLENTY OF SKEPTICISM

UH civil engineering professor Panos Prevedouros, an opponent of rail, questioned the city's ridership and congestion reduction figures.

"If rail has any impact on congestion, it will be very, very small and limited to a very narrow area," Prevedouros said. "You have to take those numbers with very huge grains of salt."

Planners see traffic congestion as a self-limiting problem, he said. If it continues to get worse, more people will either leave the state or move closer to town, easing congestion, Prevedouros said.

He also questioned the city's projections for rail ridership.

"If 65,000 people are riding rail, that would be over 20 percent of the working population," he said. "According to 2000 census figures from major metropolitan areas, only 3.2 percent of all trips were done by bus or rail. Their numbers just don't make sense."

Scheibe, the Parsons Brinckerhoff project manager, said rail transit can ease traffic because it's the only one of the major options that pulls cars out of the mix.

"You'll have faster and more reliable and frequent service on the guideway," he said. Otherwise, "it's going to continue to be congested and will become more congested. The other alternatives all depend on utilizing the highway system."

Planners have yet to select a technology for the rail line — light rail, monorail or a magnetic levitation system — but estimate the cost of any of those systems and the land acquisition will make up between $200 million and $300 million of the $3 billion.

'FEELING OF ANGER'

The other three transit alternatives being considered are doing nothing, enhancing the bus system and installing "managed lanes" (such as an elevated roadway).

"I think we can make do with what we had," said Carl Novak, a construction industry worker who commutes daily from McCully to the airport. "If they have to spend $3 billion, I sure hope it goes to local workers, not someone from the Mainland."

Added one woman, who declined to give her name, saying she had to rush off to catch a bus before it got dark: "This rail and this tax is going to break me. It's just too much for the island. I get a feeling of anger when I think about what it will do to seniors citizens like me."

PAST EFFORTS FAILED

City officials hope to present a preferred alternative recommendation to the City Council by Nov. 1. The council then will make the final selection on a new transit system.

The city hopes to have some decisions made before the new tax surcharge to help pay for transit begins in the new year. Officials hope to begin construction by 2009 and have the first leg of a system running as early as 2012.

The city expects to receive $150 million annually from the excise tax surcharge that goes into effect on Jan. 1, 2007, to help pay for the transit system. The city also is requesting substantial federal transit money.

This effort marks the fourth time in the past 25 years that the city has tried to develop a new mass-transit system for O'ahu. The previous efforts, including two rail projects and one bus rapid transit system, floundered and ultimately failed because of cost concerns or changes in local political administrations.

Reach Robbie Dingeman at rdingeman@honoluluadvertiser.com and Mike Leidemann at mleidemann@honoluluadvertiser.com.