The proposed Southwest light-rail line would bring benefits to the Twin Cities region and Minnesota. It would connect workers to jobs in the burgeoning southwest suburbs, a dynamic downtown Minneapolis and other points along a nearly 16-mile line that would travel through portions of Minneapolis, St. Louis Park, Hopkins, Minnetonka and Eden Prairie.

So why is the Minneapolis Park Board — an elected body with constituents who have much to gain from an expanded transit system — seemingly standing in the way of the project? This page is tempted to follow the lead of Gov. Mark Dayton, whose frustration with the board recently reached a tipping point, but there are reasons to consider the board's perspective — and reasons to feel hopeful that the line will be built.

There's increased federal momentum for Southwest, also called the Green Line Extension. The Obama administration budgeted $150 million for Southwest as an initial installment of a federal funding process that may pay as much as half of the project's overall $1.68 billion cost. Additionally, the Federal Transit Agency (FTA) upgraded the project's ranking to "medium-high" from "medium."

The municipal consent process that required the buy-in of each city along the corridor, as well as Hennepin County, is complete, and about 85 percent of the nonfederal funding already has been secured.

The fact that the project continues to be challenged should not be surprising, however. The Central Corridor (the Green Line) also faced significant hurdles, including objections from the University of Minnesota and Minnesota Public Radio. But a spirit of compromise eventually prevailed, and the successful line has already surpassed its 2015 ridership estimates.

For Southwest, the latest issue involves — once again — the Kenilworth corridor portion of the Minneapolis route. The current configuration calls for light-rail trains to travel over a bridge that spans a channel connecting Cedar Lake and Lake of the Isles. That section of the corridor is Minneapolis Park and Recreation Board land. Concerned over the impact the trains would have, the Park Board commissioned a study that includes options for a tunnel under the channel. The current plan includes a tunnel, but the board has questioned whether it should begin south of the channel or before it.

The federal government recognizes the Park Board's standing in the matter, and has ordered the Metropolitan Council, tasked with building and operating the line, to conduct a review. This in turn will delay the release of the project's supplemental draft environmental impact statement, which is the next step in the approval process.

Building a tunnel under the channel, which the Park Board has raised as a possibility, would dramatically raise the price of Southwest. The Met Council estimates that a "cut-and-cover tunnel" would cost $60 million to $75 million to build. A "jacked-box tunnel" would cost even more — $80 million to $95 million. Such a significant change could trigger a new municipal consent process in Minneapolis and Hennepin County, and the 2016 construction season could be lost, further driving up costs.

Avoiding such an outcome will require compromise between the Met Council and the Park Board. That will not be easy, given that in the end the project will require either a tunnel under the channel or a bridge. But compromise is necessary for several reasons, including the need to save taxpayers the additional expense of a channel tunnel, to seize on the enhanced standing the project has with the FTA and to convince Dayton to restore about $3.77 million in biennual funding he threatened to cut in response to the Park Board's actions.

We hope the Park Board will eventually see the wisdom and cost-effectiveness of the bridge option, presuming every effort is made to mitigate the impact a bridge might have on the area.

The Park Board is right, and indeed responsible, in advocating for land it is trusted to wisely use. The city's park system is one of the nation's best, contributing immeasurably to the quality of life in the city and region.

A compromise agreement on Southwest should set a precedent for future projects, including the Blue Line Extension, or Bottineau light-rail line, which would partly run alongside Theodore Wirth Park, one of the gems of a world-class park system.

Time is of the essence regarding Southwest, but next time consultation between the Park Board, the Met Council and city leaders needs to happen sooner — and be more effective.