A new potential route for light rail through Bellevue would take trains through a tunnel in the downtown business district, as city officials prefer, but would bring the tracks closer to a downtown neighborhood.

The new design, presented Thursday during the Sound Transit's Capital Committee meeting, routes trains into a tunnel underneath 110th Avenue Northeast. City officials have asked the agency to consider building a tunnel through downtown Bellevue to reduce traffic tie-ups between trains and autos, but Sound Transit has balked at the cost, estimated at an additional $500 million.

However, the new route saves money by bringing the tracks up along the east side of 112th Avenue, all the way until the trains hit Main Street, then sending light rail into a smaller tunnel under 110th Avenue. A passenger station would be located on Southeast Eighth Street.

Bringing trains along 112th Avenue all the way to downtown has been listed as an option over the years, but it has never been picked as the preferred route.

The earlier, preferred route selected by Sound Transit last year sent elevated trains in an arc away from 112th Avenue and Bellevue's powerful Surrey Downs neighborhood, which lies south of Main Street, and made a stop just south of Main Street before continuing downtown on surface streets.

The realignment along 112th Street "makes the tunnel affordable" because the agency will need to buy less property, including the Red Lion Hotel, said Sound Transit spokesman Bruce Gray. The agency will also be able to run the trains on the surface, rather than on an elevated platform.

Advancing the tunnel option means the city must agree to contribute $150 million toward the project, he said. The council has indicated it's willing to do so.

One other change: The new proposal would delay the opening of the project by a year, to 2021. During that one-year delay, Sound Transit will collect another $65 million in tax revenues, and that, too, will help close the gap, Gray said.

The Sound Transit governing board will decide April 22 whether to adopt any changes to its preferred alternative. Once it makes that decision, the agency will complete 30 percent of the engineering work needed on the preferred route. In early 2011, a final route will be chosen.

Sound Transit

The new proposed light-rail route for South Bellevue was known as B2A in the draft environmental impact statement.