A new interchange connecting Interstate 205 to 18th Street is still years away from reality, but the first stage of the project is already paying dividends for Vancouver motorists.
A new state transportation analysis shows the new 112th Avenue Connector, which opened last fall, is drawing hundreds of vehicles out of the most notorious intersection in the city: Southeast Mill Plain Boulevard and Chkalov Drive.
“It’s absolutely working like it should,” said Abbi Russell, spokeswoman for the Washington Department of Transportation in Vancouver.
Completed last fall, the $23 million connector project provides a direct connection from Interstate 205 to Northeast 112th Avenue.
In the first hour it opened, on the late afternoon of Oct. 12, a Washington State Patrol trooper counted a trickle of just 78 vehicles making use of the new connection. In the months since then, motorists have caught on to the fact that they can avoid Mill Plain if they’re headed from I-205 northbound to 112th Avenue.
A new traffic analysis shows 1,800 automobiles are using the connection during the critical three hours of the afternoon commute beginning at 3 p.m.
“It’s not going to solve all the world’s problems,” said Bart Gernhart, the DOT’s acting regional administrator. “It’s not going to do anything for the morning commute.”
But state and city transportation officials say there are 1,800 afternoon drivers who no longer have to make the labyrinthine connection to 112th through the city’s busiest intersection at Chkalov and Mill Plain. These motorists are able to slip beneath a new 1,100-foot-long bridge carrying automobiles north from Mill Plain to I-205.
Motorists using the connector halved the time it takes to get from the I-205 exit to 112th Avenue, to a shade under two minutes.
A couple of minutes may not sound like a big return for $23 million. But city and state transportation planners say the cumulative effect is making a big difference in improving safety on the freeway, easing congestion on Mill Plain and clearing the way for new development miles away from the Chkalov chokepoint.
Thayer Rorabaugh, the city’s transportation policy manager, said the financial commitment to build the project allowed the city to give the go-ahead to commercial developments along Mill Plain as far away as 164th Avenue.
He said the Target retail development on 164th Avenue, along with ancillary stores and restaurants, generates thousands of vehicle trips a day. Even a small portion of those trips would have added to the traffic paralysis more than two miles away at the intersection of Mill Plain and Chkalov — violating the state’s growth-management law.
“We would not have allowed that,” Rorabaugh said.
With the commitment to unclog the intersection, Rorabaugh said, the city was able to permit new construction along a wide swath of the Mill Plain corridor. A mile west, Southwest Washington Medical Center’s new Firstenburg Tower and a new Vancouver Clinic building both could have been caught up in a building moratorium due to congestion at Mill Plain and Chkalov.
“That’s why this was so important,” Rorabaugh said.
A similar situation afflicted the Salmon Creek area, where county and state officials last week celebrated the start of a $133 million project to ease the notoriously congested 134th Street overpass across I-205 and Interstate 5.
Safety improvements were immediate with the 112th connector.
Previously, northbound traffic routinely backed up for a quarter-mile onto I-205 during the afternoon commute as motorists queued up on the exit ramp to Mill Plain. Now, a sizable chunk of those northbound vehicles bypass Mill Plain altogether on their way north to 112th Avenue.
“We rarely get backups now,” said Allen Handy, the DOT’s assistant area engineer. “And before, we’d get backups all the way on to the main line.”
Eventually, motorists will be able to follow the same I-205 exit all the way north to a new interchange at 18th Street. Construction of that $86 million project is due to start in 2014.
Erik Robinson: 360-735-4551, or erik.robinson@columbian.com.
