Metro officials are figuring out what to do with 17 bus routes that run along or cross Highway 40 between St. Louis and Frontenac, Metro chief executive Larry Salci said Monday.

To keep service at the same level during construction, Metro will need to put 32 more of its buses into use, stretching its fleet to its maximum. Salci put the cost of running them at $6 million to $7 million.

"The question becomes, where do we get that money?" Salci said.

Plans for rebuilding 10.5 miles of Highway 40 (Interstate 64) will involve closing entire sections in 2008 and 2009. Lanes between Ballas Road and Interstate 170 close first. Once that section is rebuilt, the section between I-170 and Kingshighway closes.

Bridges throughout the corridor also will close at various times for demolition and rebuilding.

Between 25,000 and 30,000 motorists must change their commuting habits, or alternate routes will become clogged, the Missouri Department of Transportation says. Officials suggest commuting during nonrush times, working from home, carpooling or using public transportation.

"Transit has to be part of the solution here," Missouri Transportation Director Pete Rahn said Monday.

Yet there's no provision in the department's agreement with Gateway Constructors, the contracting team selected to do the $535 million rebuild, to pay for additional buses and trains to alleviate the resulting traffic congestion.

The Transportation Department is constitutionally restricted from spending highway dollars on mass transit, Rahn said. He added that MoDOT will work with Metro to help keep current bus and light rail service.

"We're going to continue a conversation with them," he said, emphasizing the importance of mass transit. "It needs to be a viable option."

The Highway 40 rebuild comes as Metro faces a $28 million budget shortfall in fiscal 2008, which begins next summer.

Metro's operating costs are rising partly because of MetroLink's new Shrewsbury line. The line costs $14 million to $15 million a year to run. Fares cover about a third of the cost.

Maintenance issues are building on the oldest part of the main line, between East St. Louis and Lambert Field. Debt payments on bonds are coming due, at $8 million a year. And, Metro also must account for its pension differently.

Salci said he is speaking with Missouri legislators about a one-time appropriation that would help keep today's service levels for another year, until St. Louis County officials ask voters for a quarter-cent sales tax increase.

Bus ridership is on the rise, due in large part to periods when gasoline prices rose above $3 a gallon. Daily boardings on MetroLink are 67,000 to 68,000, said Dianne Williams, Metro's communications director.

"Gas prices did change people's minds about using public transportation," she said. "It is possible the same thing will happen with I-64."

In coming weeks, Metro officials will analyze the construction plans. Also in question is how they'll use the Ballas Road bus transfer center, which helps get workers to medical facilities at the western edge of the corridor. They're also examining how construction will increase parking demands at MetroLink stations.

Theoretically, Salci said, Metro is in a good spot to ease congestion when Highway 40 work begins.

"We should be in a position to be of positive assistance in mitigating those impacts," he said. But he added that the agency "could become, if this funding issue is not addressed, a contributor to the problem."

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