Major work is under way on two drawbridges that are some of the last of their kind in Oregon.
Major work is under way on two drawbridges that are some of the last of their kind in Oregon. Crews with the Oregon Bridge Construction Company of Stayton, Ore., began work last fall on the Lewis & Clark River Bridge and Old Youngs Bay Bridge. The work, budgeted at $16.7 million, is scheduled to continue over the next two years.
In December, workers closed the Lewis & Clark River Bridge for major rehabilitation that will keep the bridge out of use until August.
The Lewis & Clark River Bridge was built in 1924 and is the only remaining single leaf bascule draw span in Oregon. Work also is ongoing on the Old Youngs Bay Bridge, one of only four remaining double bascule bridges in the state. It was built in 1921.
A bascule drawbridge uses a counterweight that balances the span throughout the entire upswing. The counterweights go down and the span goes up and the boat is able to pass through. When the counterweight goes back up, the span comes down.
“They are old, somewhat unique and even somewhat obsolete,” said Lou Torres, spokesman of the Oregon Department of Transpiration. “They have a lot of parts that are hard to find and the equipment is old. On the Old Youngs Bay Bridge, we are currently repairing and replacing the entire electrical and mechanical systems, and it’s the original 1920s equipment. It’s long past it’s useful life.”
The parts can be so difficult to find that in many cases they have to be specially ordered and custom fabricated.
Both of the bridges are in the Astoria area and are “life line” transportation routes. “People really count on them for their livelihood,” Torres said. “Any time you do any work, you really have to be sure people understand what we are doing and why we are going it.”
The bridges also are critical to the smooth flow of marine traffic.
Work on both bridges includes repairing the approaches, which are supported with the original treated wood substructures that have deteriorated timber piles, sill caps and cross bracings. Crews also will replace the Lewis & Clark River Bridge wooden under-course, which has deteriorated, causing continued failure of the asphalt surface, and repair and coat the steel bascule lift spans, which are corroded and rusted.
“Some of it is in-water work under the bridge,” Torres said. “There are certain marine requirements regarding when you are allowed to do that. We have to build some platforms we can work on below or under the bridge so we can move cranes in there. Any time you are working on these bridges you are working in an environment you have to careful with. You don’t want to pollute the water, hurt the fish. You’re in an environment that is not your typical environment. Also, marine traffic has to go under the bridge. All those things have to be accommodated. So far it’s working out well.”
While the in-water work calls for extra care, Torres said it is not unusual.
“We do a lot of maintenance work on these bridges all the time,” he said. “We actually have a bridge crew assigned to Astoria maintenance. That’s all they do. That’s how much it is for us to maintain these bridges.”
While the Lewis & Clark River Bridge is closed, mariners and vehicle traffic are being rerouted to the Old Youngs Bay Bridge which connects to Highway 101 farther west. The Old Youngs Bay Bridge will not be closed, but there will be occasional lane closures.
The project has been on the drawing board for at least four or five years, Torres said.
“It’s not simple to just do this kind of work,” he said. “You have to work out how you are going to do this. You have to do a lot of homework, figure out what work needs to be done, what work needs to be included in the contract. That took a while. We had engineers. We had people who specialize in these older bridges. It’s amazing how many bridges in Oregon have these wood substructures. You have to have people who know what they are doing. It’s unbelievable to some extent.”
The state put the word out about the project early, hoping to avoid confusion and keep traffic to businesses in the area flowing.
“We advertised that local businesses are open,” Torres said. “We’re trying to go out of our way so businesses aren’t hurt. People are getting round to them OK. The bottom line is we have these two 90-year old bridges that just flat out need a lot of work. You can only put so many Band-Aids on them. At some point age catches up and you have to replace some of the major components and parts that’s the case here.”