A incongruous white Metro Transit van toddled carefully along the Cedar Lake bike trail earlier this week, causing some bewilderment among the path's bikers and joggers.

A group of transit planners, elected officials and reporters tumbled out of the van, and were soon peering at the horizon where a 10-foot concrete wall will be built to separate freight trains from the proposed $1.9 billion Southwest light-rail line.

The $20 million crash wall, or "corridor protection barrier" in technical parlance, has drawn fresh criticism — and cost — to an already beleaguered project that will link downtown Minneapolis to Eden Prairie.

The 1.4-mile stretch of the route in Minneapolis where the wall would be built is controlled by BNSF Railway and located between the planned Royalston Avenue/Farmers Market and Bryn Mawr stations. Much of the route winds through an industrial underside of the city, an area that has been eyed for transit-related development for at least a decade as the Southwest project inched forward.

The wall was a late addition to the project, part of a broader $58.5 million agreement between the Met Council and BNSF and Twin Cities & Western Railroad that is still not complete. The council approved it during a three-day stretch last month with little public input — prompting outcry from Minneapolis officials.

BNSF says it needs the wall for safety reasons, "based on our experience with light rail operating next to us." Similar transit barriers have cropped up elsewhere in Maryland, California and Denver at the behest of powerful rail companies. Yet other railroads sharing part of the Southwest corridor — Twin Cities & Western and Canadian Pacific Railway — required no such walls.

The Met Council will conduct an environmental review that is required because the wall is located in the Great Northern Railway Historic District, which stretches to North Dakota. Ultimately, the Federal Transit Administration will determine this December whether more study is needed — or not.

But that doesn't appease state lawmakers from Minneapolis who think a more thorough environmental review is needed before any concrete is poured.

"I don't think it's satisfactory," said Rep. Frank Hornstein, DFL-Minneapolis. "The reason an environmental review is important is that it guarantees a thorough examination of various issues and it gives the public the opportunity to look at these issues. There are important unanswered questions about the impact of the wall related to noise, wildlife, water and drainage, and its aesthetics."

The tours given to elected officials this week were part of an "outreach plan" crafted by the council to allay those fears and answer questions about the wall. The tours will be rolled out to interested members of the public, as well.

A series of pink stakes along the route show the path of the wall, parts of which will reach just 4 to 6 feet where light rail will be elevated in spots.

"The tour for elected officials and staff was a good start, but this is happening after Met Council already voted, so now the Met Council needs to involve the community through the rest of their outreach plan," said Peter Wagenius, the Minneapolis representative on the Southwest Corridor Management Committee, a group of appointed and elected officials who help guide the project.

The Bryn Mawr neighborhood, which has its own station along the line, is closest to the proposed wall. Despite the late (and quick) addition of the wall, most residents support the Southwest project, said Kevin Thompson, president of the Bryn Mawr Neighborhood Association. "People are more worried about what it will look like," he said.

Southwest transit planners said Friday a community work group will be formed to offer suggestions on the wall's design, and the council will engage community groups in the Bryn Mawr and Harrison neighborhoods.

"Of course, we always have to be mindful of our budget," said Jim Alexander, Southwest Project Director, noting design measures to mitigate the wall's severity include adding color, texture, inlays and vegetation.

Unspoken on the tour was whether such a wall will be required of the planned 13-mile Bottineau Blue Line LRT project, which would link downtown Minneapolis to Brooklyn Park. The Bottineau line would operate along eight miles of BNSF right of way. Crash barriers there could amount to a big expense.

"Regarding the Blue Line, we take each project one at a time, and would look at specifics for each corridor," BNSF spokeswoman Amy McBeth said in a statement. "We haven't fully engaged in those discussions yet, but safety considerations would again be among the key considerations of any discussion."

When asked about a potential Blue Line wall, Met Council Chairwoman Alene Tchourumoff demurred. "It's a different corridor, a different context," she said.

Janet Moore • 612-673-7752 @MooreStrib