The work week at the core of the nine-day closure of the Interstate 5 Bridge is coming to an end, and Vancouver commuters appear to have dodged the worst of the predicted traffic apocalypse, apart from a few bumps throughout the week.
The northbound span of the twin bridges has been closed to all traffic since Saturday while crews replace a cracked trunnion and other lift system components on the bridge’s south tower. Both freeway directions are sharing the three-lane southbound span in the interim.
The crossing is a notorious traffic bottleneck to begin with, and officials at the Oregon and Washington departments of transportation spent several months warning Clark County and Portland residents that the 50 percent reduction in capacity would lead to 4-mile-long backups unless commuters planned ahead by working from home or changing their schedules.
For the most part, commuters appear to have listened. The first days saw moderate freeway congestion, but traffic has largely kept moving and WSDOT and ODOT officials said that overall traffic volumes have been lower than usual.
The single-lane crossing on the southbound span has been the most consistent source of congestion. The middle lane of is functioning as a reversible rush hour lane, meaning southbound traffic gets two lanes in the morning and one in the afternoon, and northbound gets the opposite.
Each morning has seen a persistent slowdown in the last mile approaching the bridge on I-5 northbound as drivers merge from three lanes down to just one. After the middle bridge lane reverses at noon, the same pattern occurs on I-5 southbound, with backups typically stretching to around the Main Street interchange in Vancouver. That’s a pattern that transportation officials were expecting.
“Traffic has been slow but certainly steady,” said ODOT spokesman Don Hamilton. “There’s always a little congestion when we shift the alignment to one lane in one direction or another.”
The single-lane configuration on the I-5 Bridge does mean that any traffic disruptions can quickly become freeway-blocking jams, such as a three-car pileup that occurred on the bridge’s sole southbound lane Monday afternoon, blocking southbound traffic for about half an hour while tow trucks backed up across the bridge one at a time to remove two of the damaged vehicles.
The Interstate 205 Bridge has stayed relatively smooth throughout the week, although it has seen its share of rush hour backups, particularly during the evening commute. WSDOT officials also observed a spillover effect on Monday; I-205 southbound started to jam up shortly after the crash blocked I-5 southbound.
Tuesday and Wednesday didn’t see any incidents of the same scale, but Hamilton stressed that motorists should stay mindful of the I-5 Bridge’s reduced 40 mph speed limit and drive carefully, especially with the arrival of a rainstorm on Wednesday.
The heavy rain prompted officials at the Washington State Department of Transportation to close the ramp from northbound I-5 to downtown Vancouver Wednesday afternoon due to pooling water on the freeway median.
New transit options
The I-5 Bridge project has served as a test run for a new hybrid bus-on-shoulder lane that C-Tran and WSDOT installed along I-5 south through Vancouver this summer, from 99th Street to the bridge. When traffic drops below 35 mph, bus operators are allowed to move into the shoulder lane to bypass jam-ups.
ODOT implemented a similar measure on the shoulders of both directions of Interstate 205 across the Glenn Jackson Bridge and extending south to Airport Way in Portland.
Buses used the new shoulder options 22 times during the first four days of the project, C-Tran spokeswoman Chris Selk said Wednesday – nine times on Saturday, four on Monday and nine on Tuesday.
“The vast majority of these usages are during the p.m. commute,” she said.
All but two of the instances were on I-205 rather than I-5, she said, possibly due to the eastern freeway shouldering a heavier-than-usual proportion of the area’s commuting traffic during the I-5 Bridge closure.
C-Tran will have to wait and see whether the balance of hybrid shoulder use shifts more toward I-5 once the closure ends and traffic levels adjust back to normal, she said. The hybrid lanes are permanent upgrades and will stick around once the bridge closure ends.
The trunnion project is on track to wrap up Sunday with the northbound span scheduled to reopen at 11:59 p.m. that evening. Immediately following the reopening of the northbound span, crews will close the left lane of the southbound span for seven days to perform wrap-up work and maintenance.