| ODOT "hits the skids" to conquer hilly obstacle |
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| ODOT "hits the skids" to conquer hilly obstacle |
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Winding through the pristine Coastal Range, Oregon 38 connects Interstate 5 to the coast and is a popular route for travelers. But for the 312 citizens of Elkton, many of whom are separated by farmlands, woodlands and hills, Oregon 38 is more than just a scenic route, it is their connection to each other.
Near Elkton, Oregon 38 confronts a hill so steep that the highway must pass through a tunnel. Leading up to the tunnel on the east side is a bridge that traverses Elk Creek, built so closely that it presented ODOT with a major engineering challenge: how to replace the bridge without being able to build the usual detour structure to carry traffic during construction.
To help keep the residents of Elkton connected to each other, their schools and their businesses, ODOT turned to a creative approach called rapid replacement.
“Rapid replacement allowed us to complete the bridge replacement in record time, with minimal impact on traffic and the community,” said Steve Narkiewicz, project manager for ODOT’s Bridge Delivery Unit.
With this technique, crews build a new span beside the old one and then, during a short closure, slide the old bridge out of the way and the new one into place.
Without rapid replacement, the drivers of Elkton—as well as valley and coastal motorists who use Oregon 38—would have faced several months of one-lane traffic at the bridge. Instead, crews needed to close the highway for only three days.
According to Rebecca Swearingen, mayor of Elkton, the townspeople appreciated the lessened impact on their daily lives.
“These bridges mean a lot to us in terms of maintaining our connection to each other,” said Swearingen. “This has been a great experience for our town.”
Removing the old bridge and installing a new one is tricky, so ODOT partnered with specialty contractor Mammoet, a company that pioneered the development and use of hydraulic skidding systems.
“With skidding, you can move very heavy loads over short distances, which came in handy, considering the new bridge is 222 feet long by just over 38 feet wide, and it weighs more than 2,000,000 pounds,” Narkiewicz said.
In planning for the west side Elk Creek Bridge replacement, ODOT had the option of building a detour structure. However, because all the equipment is in place, and the eastern bridge replacement was such a success, it will be more cost-effective to use the same technique again.
Looking ahead, rapid replacement is going to be more and more useful, especially in areas with physical constraints, where detour routes are challenging and in cities with heavy traffic. ODOT’s increased experience with the technique will be valuable to the agency in the future.
“Overall, the rapid replacement method was a huge success,” Narkiewicz said. “It’s not the first time we’ve used this technique, but it’s rare enough that each instance teaches us something new about the process.”
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