Last week, light-rail transit in the Twin Cities quietly passed an important milestone.

Following a vote of the Metropolitan Council, the Bottineau Blue Line extension, which is designed to link downtown Minneapolis with Brooklyn Park, officially cleared the environmental review process. Earlier in September, the Federal Transit Administration — expected to pay half of the project's $1.54 billion cost — also signed off on the project's environmental studies.

The route for the project and its price tag were approved by the Met Council, too. Now, the project will move into the engineering phase, when, among other things, construction contracts go out to bid. The line is scheduled to open in 2021.

In a news release last week, the Met Council noted it will seek the state's $150 million share in next year's legislative session. The Council will, once again, push for at least a half-cent increase in the existing metro-area transit sales tax. Revenue from the tax would help fund Bottineau LRT and other transit projects.

It will be interesting to see whether the fight over Bottineau will be as caustic and divisive as the one involving the Southwest light-rail project, which would link downtown Minneapolis with Eden Prairie. Other transit projects hang in the balance, too.

Partisan disagreement over Southwest LRT pretty much cratered bonding and tax bills during this year's session and left transit backers scrambling to find other sources to cover the state's 10 percent share. Met Council Chair Adam Duininck says another shot at the Legislature is worth it, partly because Bottineau enjoys more bipartisan support than its Southwest sister. "Maybe the dynamic around transit will change," Duininck said.

It's also unclear how the upcoming legislative election will affect the transit vox populi.

The Southwest line, which has attracted legal challenges, wasn't the only transit project left wanting this session. The $150 million Orange Line bus-rapid transit project, planned for along Interstate 35W between Minneapolis and Burnsville, failed to garner $12 million requested from lawmakers. Overall funding for that project is caught up in a bitter squabble among members of the Counties Transit Improvement Board, which was supposed to cover almost a third of its cost. The dispute erupted after Dakota County voted to leave the group, charging that it failed to get its money's worth.

And then there's the Northstar commuter rail line, which now runs limited routes from downtown Minneapolis to Big Lake.

A group of transit advocates lobbied hard this legislative session to extend the line to St. Cloud. That was the original plan of the commuter line's planners, but then federal money fell short. So when Northstar opened in 2009, the terminus was in Big Lake. Now, there are buses connecting Big Lake to St. Cloud.

Supporters argued that St. Cloud is a natural stop for the line, claiming students from St. Cloud State University and St. Cloud Technical & Community College would be inclined to hop aboard, as well as those frequenting the St. Cloud VA Health Care System. But the effort failed to gain traction at the Legislature. (The Met Council wasn't involved in the push; St. Cloud is beyond the regional planning body's jurisdiction.)

Northstar, which stops in Fridley, Coon Rapids, Anoka, Ramsey and Elk River, has struggled to attract riders. Last year, Metro Transit said ridership was 722,637, with 2,548 in average weekday rides, up slightly over 2014. As a result, taxpayers subsidized passengers to the hefty price of $13.73 apiece in 2014, the most recent figure available.