Minneapolis park commissioners are poised to ask federal transit officials to force the Metro Council to do additional engineering studies that park officials contend are required to settle the bridge vs. tunnel issue for the Southwest light-rail crossing at Kenilworth channel.

The Minneapolis Park and Recreation Board also will be asked at its meeting Wednesday to double its own investment in engineering studies it contends should be done by the council to determine if there is a reasonable alternative to the council’s proposed bridge for the rail crossing at Kenilworth.

A staff-proposed letter to the regional office of the Federal Transit Administration seeks a meeting to outline Park Board concerns and begin consultations it believes are required by law. That chiefly involves meeting the federal requirement that there aren’t feasible alternatives to the bridge, which the Park Board contends the ­council’s Southwest project office hasn’t studied sufficiently. Federal law bars taking parkland unless no feasible and prudent alternative exists.

Metro Council officials couldn’t be reached immediately Friday night. But they said in a statement in October that the council is continuing to work with the board on the design of the bridge and the adjacent corridor.

The proposed bridge is part of the routing of light rail to join freight rail and recreational trails already in the tight Kenilworth corridor; the bridge would cross a channel connecting Lake of the Isles and Cedar Lake. South of that bridge, the council proposed a 2,200-foot shallow tunnel it said adds $100 million to the project cost. The council has said that extending that tunnel under the Kenilworth channel would add another $75 million, and the resulting delay would raise the cost of the project by another $50 million to $55 million.

The Park Board previously hired the Brierley Associates Corp. for $245,500 to assess the feasibility of a channel tunnel.

That produced two options. For one, the ground would be excavated, a tunnel structure built, and then covered. The other would insert a concrete box tunnel into a pit leading under the channel and push or pull it into position.

Now a second proposed contract for $248,275 would examine the prudence of those approaches, including noise, vibration and impacts on surface and groundwater. The board previously authorized spending up to $500,000 on the studies.


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