Building a southbound HOV lane on Bellevue Way Southeast in conjunction with Sound Transit's planned light-rail line would bring critical congestion relief during and after construction, the Bellevue Chamber of Commerce says.

In a letter sent Monday to Mayor Conrad Lee, Chamber Chairwoman Janet Ray and President and CEO Betty Nokes said building the HOV lane while shifting Bellevue Way westward to accommodate a surface rail line next to the historic Winters House would achieve a longstanding goal of the Chamber at a fraction of the cost of building the lane as a separate project.

Moving the light-rail line out of a planned trench beside Bellevue Way is one of the ideas that negotiators for the City Council and the Sound Transit board have tentatively agreed merits detailed engineering and environmental study.

The Chamber of Commerce also endorsed the concept of moving the downtown Bellevue station from an underground location at 110th Avenue Northeast to Sixth Street east of 110th.

Ray and Nokes said the Chamber is concerned construction of the 110th Avenue station would increase traffic congestion because it would involve excavating below Fourth Street, "the second busiest arterial in downtown Bellevue."

The Chamber letter echoed some concerns about downtown traffic expressed last week by another business group, the Bellevue Downtown Association. BDA directors warned that a scaled-down 110th Avenue station would be unacceptable if it meant permanently closing one or more lanes of 110th.

The BDA also expressed concern that a Sixth Street station could mean fewer riders.

A draft agreement between the city and Sound Transit calls for studying station options on 110th Avenue and Sixth Street and a rail crossing underneath an elevated 112th Avenue Southeast near Southeast 15th Street.

Sound Transit also would study how to provide vehicle access to the Surrey Downs neighborhood if Fourth Street were closed to accommodate a surface rail line along 112th Avenue.

Keith Ervin: 206-464-2105 or kervin@seattletimes.com