City officials hope $3M project is final fix for blue bridge

Plans are now being laid for a $3 million overhaul of Duluth's pedestrian bridge in Canal Park, but the structure has been plagued with operational problems since the day it opened in 1991.

Dan Russell, executive director of the Duluth Entertainment Convention Center, recalled the bridge dedication, saying that it worked for four days and then broke. He was also there for a rededication ceremony three weeks later, but said the blue bridge has remained notoriously unreliable, despite numerous attempts to make it work properly.

In 2015, breakdowns rendered the bridge inoperable for 32 days, causing headaches for inconvenienced DECC guests, some of whom threatened to cancel future events at the facility.

The bridge provides a crucial link, connecting the DECC with Canal Park, and even though it has frequently been closed to foot traffic for repairs, about 600,000 people use it to cross Minnesota Slip each year.

Problematic design

The bridge's deck is lowered and raised in two sections via a winch-and-cable system. When those platforms are raised in an upright position, they can catch a lot of wind, said Jim Benning, Duluth's director of public works and utilities.

"Our biggest issue besides the mechanical breakdowns, was the wind. When this bridge is in the 'up' position, it's like a big sail, and you've got the wind coming off the lake. When we go to lower it, the wind is holding it in place, and at the same time the cables are unspooling, and then the wind lets up, and we get slack in the cables and it falls a couple feet. Now things are out of whack on the cable spools, and they get knotted up," he said.

Benning likened the effect to backlash in a fishing reel.

Over the years, the city has tried various things to make the bridge work more smoothly, replacing cables and even installing a set of springs.

"When it's in a fully upright position, it compresses those springs, and those springs, in theory, helped overcome a wind load to push it past the center of gravity, so gravity could take over again," Benning said.

The fix now proposed would result in a bridge design that's less dependent on gravity, he explained.

"We're really looking to modify the actual mechanism - the way the bridge operates. Before it relied on gravity and cables, but going forward, it's going to use a rack-and-pinion system, so it will be driven both up and down."

Accountability

As for holding the original designers of the bridge to financial account, Benning said it appears the city was prepared to take the matter to court. But in 1995, Duluth settled its case against Krech & Ojard Consulting Engineers P.A., the firm that designed the bridge.

As part of that agreement, the city recovered $120,000. That's equivalent to about 15 percent of what the city originally spent to erect the bridge.

In return, Krech & Ojard was released from future claims involving the bridge

Benning wasn't yet working for the city at the time of the settlement. But he noted that while the case was resolved four years after the bridge opened, the city likely initiated a legal claim soon after problems with the bridge emerged.

"It took until 1995 to get the actual settlement resolved, and you know how long the legal process can take," he said.

As evidence that the city recognized design issues fairly quickly, Benning pointed to a detailed study of the bridge that was launched within six months of the structure going into operation.

Benning said that realistically, there's no one left to sue for the problematic bridge.

"The statute of limitations on construction work is 10 years, so that's already gone, as well as, more importantly, there was this settlement agreement that released them from any future claims."

The $120,000 settlement the city received now is dwarfed by the $3 million retrofit being proposed for the bridge.

But much time has passed, and Benning noted: "In 1995, the city administration considered that to be a reasonable settlement."

In lieu of other funding sources, the city plans pay for the project using a portion of tourism tax collections for the next several years.

Retrofit

Work on the bridge is expected to commence in mid-January. By May 5, the bridge will be locked in a raised position during daytime hours to make way for marine traffic

The retrofit should be complete and the bridge returned to fully operational condition by June 7.

Benning said the bridge will be repainted a similar shade of blue, with that work slated to begin in late October.

LHB, with offices in Duluth, and Hardesty & Hanover, a New York City firm, have been enlisted to work on the project. Benning said the latter firm specializes in moving bridges and has been involved in past improvements to the Aerial Lift Bridge, as well.

The engineers will be required to deliver high-quality results, Benning pledged.

"We'll have the same expectation that we have of any of our consulting engineers that what they design for us will function properly and be constructed properly, because they're also going to have some construction oversight for this project, so they're going to be on site for the construction phase," he said.

If their work on the pedestrian bridge doesn't measure up for some reason, Benning said the city will pursue all available remedies.

"There have been times in the past where projects have not gone quite right, and we've collected from consulting firms for their project not going perfectly," he said. "We get compensation so the error can be corrected."

But Benning expects the better results for the pedestrian bridge.

"I'm hopeful and confident that this repair is going be what it needs to be to get this bridge up and functioning properly. That's not to say it's never going to break down. But it should be far more reliable than it currently is," he said.