A 54-hour shutdown of Interstate 5 this weekend will send tens of thousands of cars onto other nearby freeways and local streets in Vancouver.
The closure will affect both directions of I-5 while crews tackle around-the-clock work in Salmon Creek. It's scheduled to last from 11 p.m. Friday to 5 a.m. Monday.
The Washington State Department of Transportation is urging drivers to plan ahead, use alternate routes or, if possible, stay home to reduce congestion.
But it could be messy anyway.
"Obviously when you do something on this scale … you're going to get congestion and backups," said WSDOT project manager Allen Hendy. "There's nothing you can do to prevent that. All you can do is minimize it."
The I-5 closure will allow crews to set a dozen girders over the freeway as part of the Salmon Creek Interchange Project, an effort to remake the northern convergence of interstates 5 and 205. The girders form the backbone of a new bridge that will eventually carry Northeast 139th Street over both freeways.
Southbound I-5 will be closed between Interstate 205 and Northeast 134th
Street. Northbound I-5 will be closed from state Highway 500 to I-205. That means all vehicles traveling north on I-5, unless they get off sooner, will be diverted to Highway 500.
"(Highway) 500 will basically be I-5 for the weekend," said WSDOT spokeswoman Heidi Sause.
To handle the extra load, WSDOT will give highway traffic permanent green lights at the intersections of Falk and Stapleton roads. Vehicles on those local streets can still access Highway 500, but only by right turns, according to WSDOT. Travelers hoping to cross Highway 500 will have to use overpasses at Northeast St. Johns Boulevard or Northeast Andresen Road.
To avoid the I-5 closure, the best bet for pass-through traffic is I-205, according to WSDOT, along with either state Highway 14 or Portland's Interstate 84. Local travelers can try Highway 500 or stay on city streets.
Several local events figure to be impacted by the freeway shuffle. Some Clark County residents heading to Saturday's Spirit Mountain Casino Grand Floral Parade in Portland will have to use I-205 to get there. And Saturday's Healthy Kids Fair at Legacy Salmon Creek Medical Center will bring more traffic even closer to the action.
"We have our biggest annual event on the day that I-5 is completely closed," said Legacy spokesman Brian Willoughby. "But we're not terribly concerned. We think we'll be just fine."
The event has drawn anywhere from 1,500 to 2,000 people in past years, Willoughby said. That number may drop this year. But two of the three freeway exits that access Legacy Salmon Creek -- from northbound and southbound I-205 -- will be unaffected by this weekend's closure, Willoughby said. Even with no public hospital access from I-5 north, people can still use Highway 99 or other local routes to get to the health fair, he said.
"There are enough alternatives that we think things will run smoothly," Willoughby said.
Northbound I-5 won't be completely off-limits during the closure. Even as crews take advantage of empty lanes to complete maintenance work, WSDOT will still allow emergency vehicles to use the freeway up to Northeast 134th Street if needed. That includes "pretty much anyone with lights and a siren," Sause said.
WSDOT executed a similar closure on I-5 as recently as 2006 for a widening project in the same area. That caused significant backups at the time, which officials are hoping to avoid with better communication and timing this time around, Hendy said.
As for this weekend's work, hoisting a dozen 165-foot concrete girders over I-5 will require careful choreography. It will also require three large cranes, Hendy said. Two will sit on opposite sides of the freeway, assisted by a third crane sitting in the middle of I-5. Each girder weighs about 175,000 pounds.
WSDOT will coordinate a similar dance on I-205 later this year. But closures on I-205 will be overnight only, and only affect one direction at a time, Sause said.
The entire $133 million project is expected to be finished next year.
Sause encouraged people to check travel conditions before they hit the freeways this weekend. Traffic cameras are available on WSDOT's website. Drivers can also dial 511 for traffic updates.
"The more informed people are before they head out the door," Sause said, "the smoother the weekend is going to go."