The state is considering tolling the I-5 express lanes through North Seattle, charging drivers up to $5.50 for a faster commute.
For drivers able and willing to pay, the toll would shave six minutes off a rush-hour trip, a preliminary report estimates. Daily traffic would increase in the other lanes, and make the commute there slower.
Carpools of three or more people wouldn't have to pay.
Toll revenue could support $185 million in construction bonds to help pay for repairs on the aging highway, or for improvements such as adding a third northbound lane downtown.
Money would be collected electronically, primarily through the "Good to Go" windshield transponders, when cars cross the Ship Canal Bridge.
Tolls might begin in five years, and vary from $1.55 midday to $4.30 in the morning peak or $5.50 in afternoon peak, in 2016 dollars.
Such a move would require an act of the Legislature.
"We should at least do the first beginning look at it," said House Transportation Chairwoman Judy Clibborn, D-Mercer Island. "We don't have a viable way to repair and maintain I-5, so maybe we should know if it's a viable option."
State Department of Transportation managers explained the idea Wednesday in Seattle to the Legislature's Joint Transportation Committee.
Rep. Mike Armstrong, R-Wenatchee, said the discussion was premature, until the Legislature looks next year at other funding sources. Such tolls amount to making drivers pay for infrastructure they've already paid for, he said. Tolls should create new capacity, he said.
"People are only going to be interested in what makes their life easier. That's building more infrastructure."
The 46-year-old freeway was to be improved using gas-tax revenues approved in the mid-2000s. But the state grossly overestimated that revenue, now constrained by the recession and more fuel-efficient cars, along with little or no increase in driving.
DOT officials said I-5 express-lane tolls aren't meant to help counter toll diversion from the Highway 99 tunnel project, where possible peak tolls of more than $4 are expected to send thousands of drivers to Interstate 5 or surface streets.
One way to limit that diversion is to toll all the major incoming roads — an idea aired recently by the Nelson/Nygaard consulting firm, in a report for anti-tunnel Mayor Mike McGinn.
In 2003, a study for then-King County Executive Ron Sims suggested tolling all major highways in the Puget Sound region to reduce congestion.
Clibborn said the 2012 Legislature won't act on I-5 tolls, but would consider a more thorough study of income. Tolls would be combined with new statewide transportation taxes, she said.
All the money raised on I-5 would be used on I-5, she said.
After years of acting gingerly, Clibborn said Wednesday, the state may be ready as early as next year to plan for tolled highways as a gridlike, interconnected system instead of being implemented piecemeal.
The I-5 express lanes are reversible to carry extra traffic in and out of downtown Seattle during rush hours but have fewer entrances and exits. The toll concept follows the same pattern.
However, the state also is thinking about alternatives that keep a lane in the reverse direction, to help transit. That would require barriers and costly ramp changes.
It's been a busy past few years for tolling in Washington:
There is a flat $2.75 toll on the Tacoma Narrows Bridge for drivers with a Good to Go pass, and variable tolls for solo drivers to enter the high-occupancy or toll (HOT) lanes of Highway 167 in Kent.
The state Department of Transportation was supposed to launch tolls that vary by time of day on the Highway 520 bridge in April but is running late because of technical problems.
The future Highway 99 tunnel is supposed to have time-of-day tolls, and a plan is under way for HOT lanes on I-405. Lawmakers also are looking at tolling I-90 across Lake Washington, to help close a $2 billion funding gap for 520 and to discourage drivers from diverting from 520 to I-90. A future I-5 bridge from Vancouver to Portland also might be tolled.
When the express lanes were designed in the 1950s, they were expected to carry transit trains; that idea was soon dropped, in the heyday of U.S. car culture. Last year, they carried 54,000 of the 270,000 daily vehicle trips over the Ship Canal.
The DOT estimates the tolls would cut travel time six minutes in the express lanes, but mainline traffic would increase by 12,000 cars a day, causing more slowdown for nonpaying drivers. Peak tolls could be reduced by one-fourth to improve efficiency, but raise less money.
"It will not be the people in Seattle who are the most affected. It is those of us in the North King, South Snohomish County area," said Rep. Cindy Ryu, D-Shoreline. Already, she said, "We just build in an extra half-hour just in case, then we get hit by the high parking fees in Seattle."
Transportation Secretary Paula Hammond said that besides raising money, tolls would help manage the demand for road space as populations grow.
Clibborn said it finally would bring the west side of Lake Washington into the state's toll system.
Mike Lindblom: 206-515-5631 or email@example.com