As new and proposed recreational trails proliferate along the upper Mississippi riverfront in Minneapolis, pressure is building for a foot and bike crossing of the river at a lightly used rail bridge near 26th Avenue N.

One big problem: The bridge is privately owned by BNSF Railway (BNSF), and the railroad has safety concerns about trains sharing it with pedestrians and cyclists.

Park planners at the Minneapolis Park and Recreation Board have been told by a local real estate representative for the railroad that sharing the bridge won't happen while it has active trains. The railroad makes about four deliveries weekly across the bridge to a riverside cement elevator.

"The railroad does things on railroad time and when it's convenient for them," said Park Board President Liz Wielinski, who represents the northeast Minneapolis end of the bridge. She's interested but wary of assuming responsibility to maintain it.

But the obstacles don't deter some boosters of shared use of the rail bridge, an idea dating at least to 1999.

"Why don't we do this right now?" said former Mayor R.T. Rybak, who began working toward a shared bridge several years ago. "It's time for a herculean effort and a lot of flexibility."

Although it's not uncommon for recreational trails to share railroad land, sharing bridges that still have train traffic is more problematic due to their constricted nature.

However, the single track on the BNSF bridge occupies less than half of its width.

The bridge, a river crossing between the road bridges at Lowry and Broadway avenues, already gets occasional foot traffic, despite railroad signs warning that trespassers will be prosecuted.

Shared crossings

There are a handful of examples across the nation where railroad bridges still used by trains are shared with pedestrians and cyclists. The Union Pacific has two examples, one in Portland, Ore., and another due to open for recreational use this fall across the Mississippi River at Memphis. Both involve recreational paths that are cantilevered off the side of railroad bridges.

Even more akin to Minneapolis are a short section of the Appalachian Trail on a CSX railroad bridge in West Virginia, and two Reading and Northern railroad bridges in the Lehigh River gorge in Pennsylvania. Each features a single rail track and an adjoining trail, separated by a chain-link fence.

Railroads say safety is their uppermost concern, with almost 500 fatalities nationwide involving trespassers on railroad property last year. They also say they fear the liability that could accompany shared use.

"If communities approach us on potential projects involving railroad property, we evaluate them on a case-by-case basis, considering a number of factors, with safety being the priority," said Amy McBeth, spokeswoman for BNSF.

Some proposals move forward, she said. But she acknowledged that a railroad representative more than a year ago ruled out sharing the BNSF bridge in Minneapolis while there's active rail use.

However, there are examples where trains and trails share publicly owned bridges in Minneapolis.

The light-rail Blue Line and the Hiawatha LRT Trail share a bridge crossing Interstate 35W south of downtown. The Kenilworth Trail crosses the channel linking Lake of the Isles and Cedar Lake on a public bridge where the Twin Cities and Western Railroad also operates.

The Midtown Greenway crosses two bridges shared with freight trains. In each case, a fence separates tracks and trails.

Expanding trails

The convergence of trails at the BNSF river bridge should intensify soon. West Bank foot and bike paths were extended to within a stone's throw of the bridge in 2009. Matching East Bank trails are scheduled to be completed by fall. New recreational paths stretching from the river to Wirth Park along 26th Avenue N. also are scheduled to be finished this year.

And there are more plans in the works.

Neighborhood activists hope to connect the 26th Avenue paths to northeast Minneapolis, developing a concept they call the Great Northern Greenway. The Park Board and an affiliated foundation have been seeking money for a river overlook at 26th as well as a short path connecting the 26th and West Bank trails.

Rybak said routing trails across the bridge would offer a spectacular view of downtown and would allow northeast and North Side kids a similar opportunity to what he had as a youth who could bike to the Chain of Lakes. North Side park Commissioner Jon Olson said the bridge's lack of traffic would offer "much more intimate experience" with the river than noisier roadway bridges.

Although the railroad's concerns need to be addressed, Olson said, "I think it's very doable."

Steve Brandt • 612-673-4438

Twitter: @brandtmpls