Drivers on I-405 east of Seattle are getting to their destinations faster nine months after a new express lane tolling system was added. However, projected future regional population growth and increased traffic demand could undo those gains, unless road capacity grows.
The Washington State Department of Transportation (WSDOT) has several projects planned to expand the general purpose and express toll lanes on the heavily used corridor. Some transportation policy analysts say that dual-track approach is vital for continued performance improvements on I-405.
The Current System
There are two High Occupancy Vehicle (HOV 3+) express toll lanes each on northbound and southbound I-405, on a 17 mile-stretch between Bellevue and Woodinville, and one in each direction from Woodinville north to Lynnwood. Drivers with fewer than two additional passengers must pay an electronic toll levied through gantries and transponders, or cameras which capture license plate numbers. The southern 23 miles of I-405 between Bellevue and Renton does not yet have express toll lanes.
At the July 21 meeting of the legislative Joint Transportation Committee (JTC), WSDOT officials presented their first mandated direct report to lawmakers on I-405 tolling performance.
Quarterly, cumulative progress reports to the committee are now required as part of the state’s 2016 Supplemental Transportation Budget.
As with state performance data on the first three months of the project, the newer data show that most drivers are saving time compared to before tolling started.
The exception is the segment near Bothell between state Route 522 and I-5. Congestion has worsened by three minutes since tolling started. However, there have not been any noticeable impacts to local arterial streets so far.
Rep. Clibborn: ‘Surety Of Getting Through’ Is Key
Some JTC members like State Rep. Judy Clibborn (D-41) liked what they heard. Clibborn is the chair of the House Transportation Committee.
At the July 21 meeting, she said the express toll lanes let people choose to pay for a faster, more reliable trip.
“Now we have capacity, now we have movement,” she said. “There are so many people who have surety of getting through.”
Strong Performance Data On I-405 Tolling
After two years, the tolling pilot project must be financially self-sustaining and the high occupancy vehicle (HOV) lanes must operate at a 45 mile per hour average speed for 90 percent of the time. If not, the tolling system will be discontinued.
WSDOT’s Fiscal Year 2016 3rd quarter financial statement for I-405 shows that from the start of the tolling project last fall through March, revenues were $9.8 million and expenses $3.3 million.
Performance for drivers was also strong. For the October through June period covered in the recent report to lawmakers, both express toll lanes met the speed standard. Before tolling started, the average speed in the southbound HOV lane reached 45 mph only 78 percent of the time, not 90 or more. For the northbound HOV lane, it was only 40 percent of the time.
A Focus On Adding Lanes
I-405 express tolls are meant to manage congestion, but more drivers could overload the road and force dynamic pricing higher. The population of Puget Sound will be 1.5 million greater in 2040, according to the Puget Sound Regional Council. That includes 1.2 million new jobs and a projected 40 percent increase in regional road usage.
There is already higher than expected demand in the I-405 HOV/express toll lanes. Drivers were originally expected to pay $4 or less, 90 percent of the time. Instead, that happens 81 percent of the time, according to the latest quarterly report. The high tolls are supposed to depress demand and lighten traffic but many drivers pay, anyway.
WSDOT Communication Specialist Emily Pace told Lens that “the…constraints are certainly something we’re well aware of” and the agency plans to add road capacity where needed.
That includes a general purpose hard shoulder running on northbound I-405 between state Route 527 and I-5. Construction for the $11.5 million project is expected to start next year.
The legislature has approved funding for a WSDOT project creating a new lane in each direction between state Route 169 in Renton and Northeast 6th Street in Bellevue. The agency has indicated it will seek legislative authorization to toll those added lanes. The original footprint was two more lanes in each direction on this stretch, according to WSDOT.
Other projects include a northbound auxiliary lane between state Route 520 and NE 70th Place in Kirkland and possibly supplementing the single express toll lane between state Route 522 and I-5.
Tolls are “just one tool in our toolbox that we have,” Pace said. “We definitely have to look at other ways to manage congestion.”
Balancing Pricing And Capacity
Bruce Agnew is the policy director of Seattle-based Cascadia Center, a surface transportation think tank. He told Lens that for any proposed tolling system on south I-405 to work, there needs to be more road capacity in place first, or traffic will overwhelm the tolling system.
“Technology is going to provide a lot of capacity enhancements, but in the meantime the physical footprint of the corridor needs to be widened and the off-ramps need to be improved,” he said. “We’ve got needs for more real estate.”
It’s a viewpoint shared by Mike Ennis, director of government affairs on transportation at the Association of Washington Business.
“Anytime you can build infrastructure to improve mobility, it’s a positive thing,” he said.
Ennis added that one possible solution to finance new road capacity in the future on I-405 is a “low, modest” toll rate on all lanes instead of only tolling the HOV lanes. The revenue would then directly pay for new infrastructure accessible to all.
“Drivers are going to be okay with that, because there is a direct return on their investment,” he said. “They know what it is, and they know it benefits them.”