First built in the 1960s, the Aurora-Donald interchange (Interstate 5, exit 278) in Oregon's northern Willamette Valley between Salem and Portland has seen a significant rise in traffic volume.
According to David House, an Oregon Department of Transportation (ODOT) spokesman, approximately 32,000 vehicles pass through the interchange on Interstate 5 and Ehlen Road daily. Built for a much lower traffic volume, the interchange has been over capacity at peak times for many years. In addition to the volume of traffic, issues such as the proximity of roads and access points and reduced visibility cause congestion and safety concerns.
And now contractor HP Civil Inc. of Salem, Ore., is working on improvements.
Budgeting for Two Phases
In 2017, the Oregon legislature appropriated approximately half the funds necessary to improve the situation. The first phase was designed in 2021, with construction taking place in 2022-2023, at a cost of $28.3 million. House Bill 2017 provided $25 million for Phase 1, with the other $3.3 million coming from state funds for the design phase.
Salem-based contractor K&E Excavating was the contractor on that part of the project.
The design weighed safety and traffic flow, considering both short- and long-term transportation needs. Eventually, the design turned into a concept that would minimize the footprint of a full interchange. Even with the smaller footprint, however, some private property had to be acquired for the project to proceed.
The final design is known as a diverging diamond interchange. It realigns some county roads and private property access.
Phase 1 began with tree removal to make room for a noise wall between the off-ramp and the Aurora Acres RV Park, according to ODOT spokesperson Lou Torres.
By the time this first phase was completed, crews had lengthened the northbound off-ramp to reduce backup onto the I-5 lanes. They also moved the Ehlen Road and Bents Road intersection further west and installed a traffic signal at that intersection. This allowed more intervals for people to turn from the off-ramps and more space for traffic to flow before passing the off-ramps.
Work Continues
"For Phase 2, we qualified for federal grants totaling about $59.5 million, with state funds covering the balance," House said.
Design work for Phase 2 began in 2023. Construction started last year, with completion estimated by the end of 2027, at a cost of $62.5 million.
The design — a full diverging diamond interchange that has non-freeway cross traffic move to the opposite side of the road — will address capacity issues by building an interchange that is expected to work for years to come.
Phase 2 of the Aurora-Donald interchange project, which began in 2024, "replaces an exit setup with stop signs at the end of off-ramps with a diverging diamond interchange like the Phoenix interchange on I-5 in Medford," House said.
Specific tasks under Phase 2 include:
• Replacing the I-5 bridges over Ehlen Road NE with one new bridge.
• Reconstructing the I-5 travel lanes to match the new I-5 bridge.
• Changing the section of Ehlen Road NE under the I-5 bridge to have two lanes of traffic in both directions and new accesses to the I-5 on and off-ramps.
• Lengthening and widening the southbound off-ramp, the southbound on-ramp and the northbound on-ramp — completely upgrading all freeway ramps.
• Relocating the Dolores Way and Ehlen Road NE intersection to the east.
• Adding traffic lights under the bridge.
According to Andrew Walker, previous ODOT project manager, construction is well under way at Ehlen Road. Crews are working nightly Sunday through Thursday, with occasional weekend work. Up to two lanes are closed each night, and single-lane closures are common during the day.
While the project is expected to be completed on time, Walker said drivers will notice major changes this year.
As House said, "This ODOT contract is structured similarly to other ODOT construction contracts. The primary incentive for the contractor is profit. The contractor is paid per item constructed and, therefore, is incentivized to complete the project as quickly and efficiently as possible. We do have liquidated damages (disincentives) if the contractor closes a traffic lane longer than is allowed and other similar situations."
Standard equipment and materials are being used.
"The unique part of the project is how [it] will be constructed and what the final product will be: the diverging diamond," said AJ Jacobson, the current project manager.
"This is a very small construction space on a very busy intersection with Interstate 5, two truck stops, businesses and a residential trailer park," House said.
To keep traffic moving 24/7 on I-5 and minimize lane and ramp closures, this project requires an extra level of complexity and staging, from lengthening ramps in the first phase to bridge and ramp replacement in the second phase.
The bridge replacement stage under way also means moving crews, equipment and bridge components under existing bridges and close to highway traffic and doing the work in that tight, busy space. Jacobson said much of the concrete pavement and paving will be completed on mainline I-5 under full temporary barriers to provide safety to the workers and commuters on I-5.
ODOT expects the project to ultimately make a significant difference in safety and usability.
All the traffic now enters and exits the freeway on one-lane ramps, with no signals to assist drivers trying to make nearly blind turns.
"There are two truck stops, so it is heavily used by commercial vehicles, but it is also used by residents and commuters," House said.
During peak traffic hours, vehicles are often backed up the ramp and even onto I-5, waiting to make turns at the stop signs at the end of the off-ramps. This poses higher risks for crashes involving turns and sideswipes and rear-end crashes on the ramps and I-5.
In fact, according to the Statesman Journal, crashes are frequent, with at least 12 deaths occurring on roads going to and from the Aurora Donald Interchange in the first two years after the nearby Dundee Newberg Bypass was partially completed in 2018.
"With two truck stops and [being] an ideal location about halfway between Salem and Portland, as well as a hub for agriculture commerce, this is a busy interchange for commercial vehicles," House said. "It simply does not operate like a busy interchange should." CEG
(All photos courtesy of the Oregon Department of Transportation.)
