Road construction started earlier this year to build a northbound truck climbing lane on Interstate 5 over Sexton Pass. The project will repave 17 miles of I-5 from Hugo north to Glendale, build the climbing lane and improve the safety of the curves in the southbound lanes located south of Smith Hill.
The I-5: Glendale to Hugo Paving & Sexton Climbing Lane project is designed to replace old and damaged guardrail and median barrier as well as add new signage in the project area. The 2009 Oregon Jobs and Transportation Act is funding part of the project.
Climbing lane construction required the closure of the emergency shoulder. Prime contractor Knife River Corporation of Central Point placed concrete barrier in the work zone so crews and equipment can begin the widening process.
“The long haul up from Hugo may seem a little longer this summer,” said ODOT Spokesman Dan Latham. “Until we get to the paving stage later this summer, traffic will be separated from the heavy equipment that is needed to excavate the slope for a new travel lane and shoulder.”
Latham said that means northbound I-5 traffic, depending on the time of day and season, may encounter delays and congestion as slow moving vehicles remain in the slow lane. The contractor is also currently working on Old Highway 99 and around I-5 exit 66. Motorists should use caution and watch for workers and equipment along the highway.
“Drivers need to keep an eye on the flow of traffic and watch out for slow moving vehicles and quick lane changes,” said Latham.
The Sexton Mountain climbing lane will be about 2.8 miles long, starting as an extension of the Hugo (exit 66) interchange’s northbound on-ramp end ending just beyond the crest of the mountain pass. The 12-foot climbing lane will be built where the shoulder currently exists. A new 10-foot shoulder and drainage ditch will be built to the right of the climbing lane.
Some of the steepest grades on the Interstate Highway System are located on I-5 in southern Oregon.
Commercial trucks have long used the I-5 shoulders, designed to provide a safe refuge for disabled vehicles, to navigate southern Oregon’s mountain passes. Trucks using the shoulder cause significant damage that requires frequent repair.
“Southern Oregon is one of the weak links in the corridor,” said ODOT Project Leader Mark Leedom, who managed design for the I-5: Glendale to Hugo Paving & Sexton Climbing Lane. “On each climb, trucks slow down in the outside lane, which results in congestion and increases the possibility of crashes.
While most freeway climbs are built on grades of 5 percent or less, the northbound I-5 lanes on Sexton Mountain present a 6.13-percent grade. Trucks frequently slow to less than 30 mph during the climb and the difference in speed relative to other traffic can be hazardous.
“The Federal Highway Administration recognized that some of the worst steep grade truck bottlenecks in the nation are on I-5 in southern Oregon.”
When one commercial truck attempts to pass another slow-moving vehicle, both I-5 lanes are blocked, forcing traffic to brake hard or suddenly change lanes to avoid a collision. Some trucks drove along the shoulder but this left no room for disabled vehicles.
The climbing lane is expected to reduce the frequency of I-5 closures related to commercial trucks, especially during winter driving conditions. The new climbing lanes are being built to today’s engineering standards, thereby reducing the need for on-going shoulder maintenance.
More truck climbing lanes
ODOT recently constructed three short climbing lanes, each roughly one-mile long, on I-5 in Douglas County. The truck climbing lanes are located southbound at Rice Hill (milepost 147) and one in each direction on ‘Gumby Hill’ (milepost 137) the steep grade located between Sutherlin and Oakland.
Climbing lanes can also be found further north on I-5 (a 3-mile lane south of Salem) and on Interstate 84 (a 7-mile lane east of Pendleton).
Other potential truck climbing lanes have been identified in southern Oregon, although no other projects are currently funded. ODOT will continue to build on its past success of incorporating truck climbing construction into I-5 repaving projects.
“The benefits of truck climbing lanes extend beyond Oregon to the neighboring states of Washington and California,” Leedom said.