Construction crews with the Salem-based Carter and Company began construction on the new $7.6 million bridge in June 2022, closing the existing bridge to all traffic. After building a temporary work bridge, they demolished the old bridge.
(Oregon Department of Transportation photo)
Contractors in Yamhill County, Ore., are preparing to pour the deck on a new bridge in the rural town of Amity with an eye toward completing it in approximately six months. The opening can't come a day too soon. The original wood Salt Creek Bridge — also known as Ash Swale — was installed in 1951 and expected to be in service for approximately 50 years. The Oregon Department of Transportation (ODOT) managed to squeeze an extra 20 years out of it through regular maintenance and repairs. But it hasn‘t aways been easy on travelers, especially those with bigger rigs.
"The existing bridge was an old timber bridge," said Douglas Keys, assistant resident engineer, ODOT Area 3. "It was structurally deficient, and had only a 9-ton load rating, which is really bad. About 18 tons is normal. So, if a semi was heavier than 9 tons, they were not allowed to go over the old bridge."
The weight restrictions went into effect in March 2020 and applied to vehicles including medium and large trucks, as well as school buses and large farm equipment. Those vehicles were required to detour to Highway 99W.
Construction crews with the Salem-based Carter and Company began construction on the new $7.6 million bridge in June 2022, closing the existing bridge to all traffic. After building a temporary work bridge, they demolished the old bridge.
Since beginning the construction on the new steel girder and concrete structure, crews have faced two significant challenges, pushing back the scheduled completion date from Sept. 2023 to about Dec. 2023, Keys said.
"One of them was pile driving. In Dec. 22., we hit really hard ground and weren't able to penetrate through the soil. So we basically had figure out a new method to drive the pile to the depth we wanted it. We had to go back to our internal team and figure out how we can get this to work. The original intent was to drive with a closed-end pile. We basically ended up determining we needed to change to an open-end pile and then we had to do auguring to get the pile down to the depth." That delayed the project by about a month and a half and added about $200,000 to the budget.
The second challenge involved water. Much of the project is a wetland, requiring numerous permits and requiring a sediment barrier. It's also set in an area of a great deal of farmland.
"Something unique about this particular area is that there are privately controlled dams on both the upstream and downstream," Keys said. "The local farmers control that and that made predicting the waterflow pretty difficult. The contractor would have to communicate with the farmers. The flow doesn't necessarily impact the work, but the water levels might. The contractors staging their equipment need to know where they are allowed. If water levels raise significantly, it could wash away equipment, debris could go everywhere."
That's exactly what happened last winter after Yamhill County experienced heavy rainstorms and flooded the area. "It rained very hard and very quick," Keys said. "The water level went way higher than we would think," Keys said. "There was a bunch of debris everywhere. The contractor had to spend three to five shifts just cleaning everything. That was also a delay we couldn't control."
The new bridge will be wider than the original bridge with a standard guardrail. The original bridge, Keys noted, "really wasn't safe, just timber with a skimpy rail." The new bridge will also be raised out of the flood zone and is designed to withstand a major earthquake, an event scientists say is not an "if" but "when." The Cascadia Subduction Zone, a 621-mile fault is located off of the Oregon Coast. ODOT is currently working to update all of the state's bridges to withstand major seismic activity, Keys said.
Today's top stories
