A vocal group in the East Link light rail planning process says it has the answer to Bellevue and Sound Transit’s financial dilemma.

The two organizations have worked tirelessly to find ways to cut at least $60 million in costs, for which Bellevue would be on the hook. The new report by Building a Better Bellevue, which previously advocated for rail lines on the east side of Interstate 405 away from the preferred route on 112th Avenue where many of the group’s members live, posits that running the train underground through a bored tunnel could lead to a savings between $160 and $275 million.

The current route runs at surface level on Bellevue Way and 112th, with a raised crossover from the east to the west side of the street. This route has been approved by the Bellevue City Council, Sound Transit Board and the federal authorities.

Building a Better Bellevue’s route would exit Interstate 90 and use the South Bellevue Park and Ride as envisioned by the current alternative, but it would then dip underneath Bellevue Way, and cross underground. The bored tunnel would then run along 108th Avenue Northeast all the way through a downtown tunnel. It would then exit a tunnel near Northeast Sixth Street, a cheaper option currently being discussed by the Bellevue City Council.

Proponents of the route agree that tunneling through the city costs more, but the tradeoffs more than make up for the difference.

“We acknowledge it costs more,” said Joe Rosmann, spokesman for Building a Better Bellevue. “It costs $148 million more to do [a] tunnel as opposed to their current plan. But it’s all the other things that don’t have to be done where the real savings is going to be.”

According to the group’s estimates, eliminating a station between the South Bellevue Park and Ride and downtown, along with fewer property acquisitions and mitigation measures, add up to the $275 million savings.

Rosmann said the study was conducted over a six-month time span. It was put together primarily by Bill Popp, a transportation consultant, and Al Cecil, a Building a Better Bellevue member and retired Boeing engineer. Cecil said he examined the track in 100-foot increments for estimating costs, using Sound Transit’s figures.

Rosmann said the group will present its study to the Bellevue City Council at its meeting Monday evening, after Reporter deadline.