Planners present new 'deeper shallow tunnel' option for Southwest light rail route

Another tunnel is on the table for the beleaguered Southwest light rail project.

Plans to send passenger trains to the southwest suburbs have been stalled for months over a fight between Minneapolis and St. Louis Park. But some key officials involved with the project hope that a compromise plan unveiled Wednesday could remove at least one roadblock.

• Related: Minneapolis Park Board commissioner says new SWLRT tunnel plan requires a deeper look (March 13, 2014)

Last year, light rail planners painstakingly considered the merits of two different scenarios for burying the light-rail trains through a popular recreational corridor in Minneapolis.

One plan called for building a subway-style, so-called "deep tunnel" throughout the Kenilworth Corridor, but metro leaders killed the idea because of its $330 million price tag.

The other plan would send the trains through a couple of so-called "shallow tunnels." The trains would descend underground in Kenilworth but emerge to cross a bridge over the scenic water channel connecting two of Minneapolis' most venerable lakes.

But the shallow-tunnel plan faced blistering criticism from the Minneapolis City Council and Park and Recreation Board -- two entities that could make trouble for the project if they fail to get on board.

At an advisory board meeting Wednesday, elected officials from the Twin Cities learned of a new design that blends elements of both tunnels:

"I call it the deeper shallow tunnel," said Hennepin County Commissioner Peter McLaughlin, who is cautiously optimistic about the idea.

"It would seem to directly address the concerns by the park board, those that arise out of the impacts at the channel," McLaughlin said. "Those would obviously be eliminated."

The latest plans would keep the trains beneath the Kenilworth channel, rather than sending them above ground over a bridge.

Last month, the Minneapolis park board urged the Met Council to study the latest tunnel option, which it said would preserve the character of the waterway. The Kenilworth Channel is popular with canoeists and kayakers in the summer and cross-country skiers in the winter, and park-lovers describe it as an oasis in the heart of south Minneapolis.

The previous plan would require a doubling of the bridge span that currently traverses the channel to carry the occasional freight train. At 45 feet wide, the existing bridge would have to be widened to 90 feet to accommodate freight, light-rail, and a bike path.

While Met Council engineers say they're interested in pursuing the idea, they're also quick to point out it has yet to be thoroughly vetted. Mark Fuhrmann, who oversees light-rail projects for the agency, emphasized that in planning parlance, it's far short of a proposal.

"The new concept presented today — the 'deep shallow tunnel' under the Kenilworth Channel — is only a concept presented today and would require additional technical study," he said. "We're anxious to hear the reaction. Not much discussion today, because it was brand new here at the Corridor Management Committee."

Matt Look, an Anoka County commissioner who serves on the corridor committee, said more spending on the Southwest project would means less money for future transit projects across the region.

"I feel a little uncomfortable in terms of these additional costs we keep seeing, and the willingness to now investigate a deeper tunnel to the tune of $30, $40, $50 million — as if it weren't real money," Look said.

Met Council Chairwoman Sue Haigh acknowledged that the council's staff and consultants discussed the latest tunnel concept in 2013, but chose not to advance the option because of the higher costs and the longer construction timeframe.

"It has always been technically possible, but a less desirable alternative," Haigh said. "This option was presented today to be responsive to the Minneapolis Park Board resolution."

The new tunnel option is so new that planners don't know what to call it. Early analysis from the Met Council determined that it would add a year to construction and raise the project's cost by up to $85 million.

Even though the latest tunnel concept is aimed at courting Minneapolis officials, Mayor Betsy Hodges remains skeptical. Last week, the City Council unanimously passed a resolution opposing the shallow tunnels and urged the Met Council to consider re-routing the freight to St. Louis Park.

Hodges said in a statement today that she was caught off guard by the newest design. The mayor called it a "brand new, and therefore, unstudied idea," one that comes just three weeks before Hodges and other metro leaders are expected to vote on the project.

"We appreciate the Met Council's responsiveness to the request from the Park Board," Hodges said. "However, anything that may harm our lakes needs thorough analysis, which, according to the law, the Met Council must provide."