Low-cost fix tokeep Old Steel Bridge open?

Local and state officials may have identified a low-cost repair plan that could keep the Old Steel Bridge open for another few years.

The creative effort comes two weeks after a Montana Department of Transportation bridge inspector recommended closing the 111-year-old structure unless significant repairs are undertaken.

Ben Williamson, bridge coordinator for the agency's Missoula District, found numerous signs of rotting in the bridge's wooden planking during an inspection earlier this year.

"You can step on some of the planks and depress them a half-inch to an inch," Williamson said Monday during a meeting with the Flathead County commissioners. "A majority of the timber decking is rotten and should be replaced, or the structure needs to be closed."

He estimated that replacing the entire deck - which includes both longitudinal "wear" planks that run in the

direction of travel and underlying transverse planks that run from side to side - would cost roughly $200,000.

That was not welcome news for the commissioners, who are struggling just to find the money to pay for regular county services.

Moreover, even if they spring for the repairs, it's possible the bridge would only remain in use for another 18 to 24 months.

The structure is slated to be replaced by an entirely new bridge. That project is tentatively scheduled to begin in 2007, with construction taking about two years. The current design calls for a new abutment on the west side of the river, with a second abutment close to where the existing east abutment is now.

Depending on how the contractor decides to proceed, Williamson said the Old Steel Bridge might have to be closed as soon as construction begins on the new structure.

Commissioner Bob Watne was not present for Monday's meeting. Commissioners Gary Hall and Joe Brenneman both indicated that they would have a hard time approving a high-cost repair, particularly if it only produced a short functional life.

"If we decide to do the repairs, I'm told the bridge will be closed at least two months," Brenneman said. "Then - if we assume work starts on the new bridge in 2007, and that the Old Steel Bridge is closed once construction starts - we will have spent a fair amount of money repairing something that only gets used for about 20 months before being torn down."

"There's no way we can afford to pay $200,000 for 20 months," Hall said.

However, Brenneman later toured the Old Steel Bridge with two state bridge officials. He said a more palatable alternative may have been identified.

"After looking things over, the engineers said they didn't think there was any kind of structural failure," Brenneman said. "They also thought that, rather than take everything off, we could just replace the wear boards and some of the transverse planks."

Furthermore, he said it might be possible just to lay down longitudinal "tracks" for vehicle tires to run on, rather than replace the wear boards across the full width of the bridge.

Repairs of this type would probably cost a fraction of what it would take to replace the entire deck, Brenneman said.

Finally, the engineers felt the Old Steel Bridge could remain open for at least a major portion of the construction period on the new bridge, meaning its usable life span (with the repairs) might be closer to 3 1/2 years.

Brenneman said the county bridge people still need to get involved before any decision is made about the future of the structure.

Also, both he and Hall made it explicitly clear that - whenever the bridge is closed - they want a temporary traffic light installed at the intersection of Fairmont Road and Montana 35 so that the traffic that previously used the structure could safely access the highway.

"Everyone understands that the Old Steel Bridge is going to be closed at some point," Brenneman said. "Once it is, there needs to be a safe way for traffic to get onto the highway."

Reporter Bill Spence may be reached at 758-4459 or by e-mail at bspence@dailyinterlake.com