One of the proposed options for the Southwest Light Rail Transit line would destroy a huge swath of trees along the Kenilworth corridor of Minneapolis, a top planning official told members of the Metropolitan Council today.
If officials chose to use a shallow tunnel to fit the light rail line, existing freight rail and bike trails through a narrow section of the corridor, about 1,000 trees would have to be removed to accommodate the 20-foot-deep trench and concrete cover, said Jim Alexander, the Council's design and engineering director for the project.
Even if the freight rail is relocated -- leaving only the light rail trains to run above ground -- the corridor would still lose about 600 trees during construction.
Peter Wagenius, Mayor RT Rybak's policy director, said that number is staggering. He said the tree canopy along the corridor is one of its most popular features.
"If we're proposing a relocation scenario, the city is going to make a case about aiming for preserving more -- if we can -- particularly the fully grown trees," Wagenius said.
A shallow tunnel also would have to emerge from the ground to cross a channel between Cedar Lake and Lake of the Isles before reentering another tunnel. The Met Council has planned to install sound barriers to mitigate the noise of the trains that would be traveling around 45 miles per hour over the exposed section of tracks.
Those details emerged today during Met Council meeting on the transit line, which would run 14 miles between downtown Minneapolis and Eden Prairie, and carry an estimated 30,000 riders a day.
Another option involves moving the freight rail tracks out of the corridor and through St. Louis Park -- an option strongly opposed by many St. Louis Park residents. The council also could choose to build a deep tunnel.
Much of Alexander's presentation to the members of the Corridor Management Committee -- comprised of elected officials from communities along the planned route -- concerned the shallow tunnel. But he said planners are still studying the three options.
"I don't want to give the impression that we are moving forward with shallow tunnel at this juncture," Alexander said. "We're just in the answering questions mode, primarily from the city that have been posed to us."
Minneapolis city officials have raised questions about how tunnel construction might impact the nearby lakes, trees and residents. A tunnel would run between Cedar Lake and Lake of the Isles.
Alexander said engineers hired by the Met Council have taken dozens of soil samples and determined that lake levels should not be affected.
Wagenius, who represented the mayor, told Alexander he would feel better if the Met Council got an independent assessment.
"When it comes to the chain of lakes in the city of waters, there is no room for error," Wagenius said.
In response, Alexander told Wagenius that the Met Council is consulting with both the Minnehaha Creek Watershed District and the state Department of Natural Resources on groundwater issues. The Met Council will need permits from the district and the DNR before it can begin construction.
Alexander also addressed questions about flooding risks from removing groundwater from the excavation site. He said the construction would be staggered in a way to avoid pumping large amounts of groundwater at a time.
The meeting was held in the St. Louis Park city council chambers in front of a packed room of spectators.
Although the Met Council is considering three options, some residents of Minneapolis and St. Louis Park see only two choices: relocating the freight trains through St. Louis Park, or keeping them in the Kenilworth corridor and placing light rail in a tunnel underneath. Several citizen-action groups have formed to oppose both choices.
The Met Council will make its choice at the end of next month. The transit line could at least $1.3 billion, and will connect to other metro bus and rail lines.