Gov. Mark Dayton on Tuesday said a plan to run the Southwest Corridor through tunnels in the Kenilworth corridor of Minneapolis is flawed but the “only option” for the light-rail line to advance.

His comments came on the eve of a crucial Wednesday vote on the plan by the Metropolitan Council, the agency overseeing the project. “There does not appear to be any other viable alternative to what the council will be considering,” Dayton said in an interview with the Star Tribune. “It’s the only option for the line to go forward, and I support the line going forward.”

Dayton said if Minneapolis officials continue to oppose the tunnel option, the Met Council must decide if it will proceed without the city’s consent. But, the governor said, a protracted dispute would likely doom the project, bogging it down in many months of negotiations and lawsuits.

“The federal funding would be likely to disappear,” he said. “I don’t see any practical way that the Met Council can proceed over the adamant opposition of the elected officials in Minneapolis.”

Kate Brickman, a spokeswoman for Minneapolis Mayor Betsy Hodges, declined to comment on Dayton’s remarks.

The Met Council is poised to vote on a $1.68 billion plan that includes a pair of nearly half-mile-long tunnels for the light-rail line north and south of a water channel between Lake of the Isles and Cedar Lake. The light-rail trains would emerge from the tunnels to cross a bridge over the channel.

The city of Minneapolis and some Kenilworth corridor residents oppose the tunnels in favor of rerouting freight trains to make room for light rail at ground level or building it elsewhere. Some critics say St. Louis Park reneged on a commitment to take the rerouted freight lines, a claim that city denies. Other critics say building the tunnels will result in years of disruption and that they won’t do a good enough job hiding the light rail in the corridor.

Dayton acknowledged problems with the tunnels but alluded to the difficulty of fitting light rail at ground level next to the freight lines and recreational trails at a narrow point in the corridor.

“There’s no good solution to the choke point in the Kenilworth corridor,” he said. While Hennepin County has been blamed for not resolving the potential conflict between light-rail and freight trains, Dayton said, “It could easily have been foreseen by Met Council staff, the planners and the like, at least five years if not 10 years ahead of now.”

“I cannot defend any particular route,” Dayton said, stressing that months of additional studies by consultants last fall showed that other options weren’t viable.

While one consultant said the freight traffic could be safely rerouted, St. Louis Park continued to oppose the idea, as did a railroad.

“By the process of elimination, I think the project should proceed,” he said. “If it doesn’t, certainly light-rail transit will be set back for a decade in the metropolitan area.”

On a related issue, Dayton said he insisted on restoring service and a station at the end of the Southwest line in Eden Prairie cut from earlier plans to save money. He said the extended line and additional station were consistent with a goal of the project “to connect suburban cities with Minneapolis and St. Paul.”