In "Help me understand light-rail bridge logic" (Oct. 13), Paul Linnee asks why an old bridge is so important to the Minneapolis Park and Recreation Board.

The old bridge is not the issue. The importance of this location is the parkland under, above and around the old bridge and whether the parklike setting can possibly be preserved as Southwest light rail, freight rail and a bike trail are co-located in the Kenilworth corridor.

Under a provision of federal transportation law referred to as 4(f), no federal dollars can be spent on a transportation project that impacts parkland unless there is no "feasible and prudent alternative." No federal funds can be expended on this project unless the public agency responsible for the park (the Park Board in this case) determines that the transportation impacts are "de minimis," i.e., insignificant.

One tunnel is required already. We believe a short extension of that tunnel under the Kenilworth channel would be feasible and prudent to protect park resources. Over 100 years ago, after fighting the railroads all the way to the Minnesota Supreme Court, the Park Board acquired an easement on this property to facilitate the connection of Cedar Lake with Lake of the Isles.

In effect, the Park Board created the Chain of Lakes in Minneapolis.

The Chain of Lakes is eligible for the National Register of Historic Places and forms a critical component of our city and the entire metropolitan regional park system. More than 5 million users annually visit this part of our system.

The channel is a key link in the Chain of Lakes. Besides being used for canoeing and kayaking in the summer, the channel is also used for cross-country skiing in the winter, most notably for the Loppet ski race — the biggest of its kind in the country. The channel provides access through an important and sensitive park environment.

In 1992, when the rail link crossing Hiawatha Avenue/Hwy. 55 was severed, railroad traffic was supposedly rerouted temporarily into the Kenilworth corridor. For two decades, transit planners promised that the rail traffic would go out of the corridor and be replaced with light rail.

Just over a year ago, when faced with pressure from the railroads and suburban communities, the Metropolitan Council reversed course and put freight rail in the corridor permanently. The game changed entirely. And as soon as the game changed entirely, the Park Board, in August 2013, began asking hard questions of the Met Council about the impact of both freight rail and light rail on park resources in this sensitive and confined corridor.

The Met Council did not answer.

The Park Board passed two more resolutions in the last year, again politely requesting that the Met Council provide answers to what park impacts would occur in the corridor. The Met Council did a preliminary engineering study of extending the south tunnel under the channel, and stated that it was feasible and that the cost to provide such a tunnel would be an additional $30 million to $50 million. This is less than the $81 million to add another station in Eden Prairie and fits within the project's contingency fund of $261 million.

Because of 4(f), the Park Board was successful in getting accommodations to Hiawatha/Hwy. 55 that resulted in the land bridge over the highway at Minnehaha Park. The Park Board also vigorously opposed plans for Interstate 94 through north Minneapolis until appropriate protections were made to protect park resources in that part of the city. Given the potential for irreparable harm to the park resources in the Kenilworth channel, the Park Board believes that the Met Council needs to make similar changes at this site.

Because the Met Council has refused our entreaties to include the tunnel extension in the Kenilworth corridor at the channel, the Park Board, in complete frustration, is now undertaking its duty under federal and state law to determine if it is a prudent and feasible alternative. The regulations in the 4(f) federal transportation law require the Met Council to analyze prudent and feasible alternatives.

The Met Council proposes doubling the size of the old bridge and a massive infrastructure with tons and tons of concrete. The Park Board believes that is simply incompatible with the pastoral and rustic setting that provides a haven for Minneapolitans and others who use and value the natural surroundings in an otherwise developed urban area.

The Minneapolis park system has been recognized as the best urban park system in the country for the last two years by the Trust for Public Land. One reason for this is that Minneapolitans do not simply let precious park resources disappear when faced with transportation and development demands. Our 130-year history has conclusively proven you can have both.

The Park Board is adhering to what federal law requires and believes that prudent and feasible alternates must be fully considered. To do less would be an abdication of the public trust the Park Board holds.

Liz Wielinski is president of the Minneapolis Park and Recreation Board.