Seattle has changed a lot in the 10 years since Gov. Christine Gregoire decided to replace the Alaskan Way Viaduct with a tunnel. But the debate over how best to move people and goods through the city remains.
It’s been 10 years this month since Gov. Christine Gregoire chose a deep-bore tunnel to replace the Alaskan Way Viaduct, after nearly a decade of debate about what to do with Seattle’s aging waterfront highway.
A lot has changed since then. We have …
- Added more people — well over 100,000 in Seattle since 2009, and nearly 300,000 in King County.
- Built more apartments than ever — more than 80,000 this decade in King and Snohomish counties.
- Built more light rail — 22 miles opened since Gregoire’s decision, with 94 miles planned or under construction.
- Added more jobs — more than 200,000 in the metro area since 2009.
- Ridden more buses — about 132 million bus boardings in 2017 alone.
- Sat in more traffic — it takes 95 minutes to drive from Everett to Seattle in the morning and reliably arrive at work on time.
But a decade after she picked the tunnel, which will open in early February, one thing hasn’t changed: Anyone’s mind.

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The same fundamental questions underlying the tunnel debate — what’s the best way to move people and goods through and around a city — remain. And the breakneck changes over the last several years have only cemented the arguments of a decade ago.
Does the city’s gangbusters growth mean it would have been nuts to tear down our second-biggest downtown highway, with no replacement?
Nope, say the folks who wanted to replace the viaduct with improvements to Interstate 5 and to surface streets and public transit.
Does our rapid shift to public transit — faster over the last few years than anywhere else in the country — mean people are more than willing to get out of their cars and we were foolish to cater to drivers with an expensive downtown tunnel?
It does not, say those who supported the tunnel.
Or what about the opposite approach: With a city population nearly 20 percent bigger than when we chose the tunnel, was it still a good idea to spend $3.2 billion replacing six lanes of viaduct with just four lanes of tunnel — and no downtown exits?
Tunnel supporters say we built the best possible facility with the available technology, and tunnel opponents certainly aren’t hankering for an even bigger car tube.
“To do the surface street, which was an option, if I was to look back now in light of the growth of the city,” Gregoire said, “that would have been a terrible mistake.”
Former Mayor Mike McGinn, who was elected in 2009 largely based on his opposition to the tunnel, sees it as a missed opportunity — we could have used the years and money spent on the tunnel investing in transit.
“There was this idea that there will be economic catastrophe if we don’t build the tunnel,” McGinn said. “We’ve been a very, very successful city and I don’t think it’s because it’s easy to drive around or easy to find parking. That’s actually not the secret to our success.”
The debate that resulted in the tunnel began in earnest following the 2001 Nisqually earthquake, which damaged the viaduct and revealed its potentially catastrophic seismic deficiencies.
A single deep-bore tunnel — built by what was then the world’s largest drill — wasn’t even on the table for most of those years.
The debate spanned dozens of options — reinforcing the viaduct, building a new viaduct, a cut-and-cover tunnel, a bridge over Elliott Bay, a wider Alaskan Way — and was tackled by nearly as many committees, commissions, advisory panels and stakeholder groups.
It cost about $300 million just to get to a decision.
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“Nothing that’s happened in the ensuing years has shown me that those were viable options,” state Rep. Judy Clibborn, D-Mercer Island, the longtime chair of the House Transportation Committee, said. “It took us so long to make a decision that the technology caught up to be able to build a big enough bored tunnel.”
Setting — and breaking — deadlines as region changes
If it took that long to make a decision, it’s taken even longer to execute that decision.
We’ve known since at least the Nisqually quake that the viaduct cannot withstand a larger earthquake and its collapse would be deadly.
Gregoire’s self-imposed deadline for tearing down the viaduct was 2012. The southern mile was removed in 2011, but only now is the rest about to come down.
The slow-motion removal has already blunted some of the final traffic impact. While the viaduct carried about 105,000 vehicles a day in 2009, it now carries about 90,000.
Even as the population has skyrocketed, the number of vehicles driving around Seattle — not necessarily to and from the city, just within the city — hasn’t changed all that much. Seattle was right around 1 million vehicles a day in 2009, when Gregoire made her decision, and was just over 1 million in 2017, according to the city’s annual traffic report.
But traffic, viewed regionally, is significantly worse.
Average morning travel times from Everett to Seattle were 15 minutes longer in 2017 than in 2009, when the region was still in the depths of the recession.
Average travel times from Federal Way to Seattle were 24 minutes longer in 2017 than in 2009.
When construction closed the viaduct for more than a week in 2011 and 2016, traffic impacts cascaded all over the region.
“Guess which street had the greatest increase in traffic” during the 2011 shutdown, said Bob Donegan, the president of Ivar’s Seafood Restaurants and an original supporter of the tunnel. “Interstate 405. This is a regional transportation system.”
One thing that both sides agree on today is that the tunnel will, at least in large part, serve non-Seattleites.
“With the lack of downtown exits, it’s not for people trying to get to and from work in downtown,” McGinn said.
“There are a whole bunch of people who land in SeaTac and want to get to Snohomish County and Skagit County and Canada and they don’t plan on stopping in the city,” said state Rep. Gael Tarleton, who was a Seattle Port commissioner for much of the viaduct debate. “That’s what the tunnel does.”
Tearing down the viaduct without a similar replacement, Tarleton said, would have crippled the city’s downtown maritime industry, from the West Seattle Bridge to the Magnolia Bridge.
“If we wanted a working waterfront we could not put more cars and freight and traffic on the road surface or it would kill the working terminals from Terminal 18 up to Terminal 91,” Tarleton said. “It would kill maritime jobs in Seattle.”
Waterfront businesses were similarly spooked about the prospect of a new viaduct or a cut-and-cover tunnel shutting them down during years of construction.
“If we had chosen the option to remove the viaduct first without replacing the capacity, we would have shut down downtown,” Donegan said. “If the viaduct comes down, then those … vehicles have to go to other streets and I-5.”
But tunnel opponents argued then — and now — that they do not. Some vehicles would go to other streets, they said, some would take a rebuilt Alaskan Way surface street, and some of the car trips would simply disappear, absorbed by investment in transit — light rail, bus-only lanes, more frequent bus service and a connected downtown streetcar system.
That was part of a $2.2 billion package that McGinn and others backed to replace the viaduct — improvements to I-5, transit and surrounding surface streets, but no replacement highway.
Region’s big shift to mass transit surprised planners
Tunnel planners did foresee our transportation habits changing. But not this much and not this fast.
In 2010, planners predicted that by 2015 about 34 percent of commuters to and from Seattle’s center city would use transit, and that the number would rise to about 41 percent by 2030.
Instead, nearly half of commuters already arrive using transit, while just one in four drives alone.
“We the people changed our habits, and our transportation system is still trying to catch up,” said Cary Moon, who led the People’s Waterfront Coalition, an anti-tunnel group.
“The number of people who want to take the bus but can’t because of insufficient service, the number of people who want to bike but don’t feel safe without protected bike lanes, the number of people who want to live near transit and ditch their cars but can’t afford to anymore — all signal a huge transformation,” Moon said.
The tunnel debate played out at a time when Seattle had already committed to drastically cutting its climate emissions. Building a tunnel to ease car and truck travel through downtown was at odds with the city’s climate promises, opponents said.
Since then, the city has not kept pace with those promises. And the city’s slowly escalating transportation emissions have been the biggest culprit.
In 2005, Mayor Greg Nickels pledged the city would reduce its greenhouse-gas emissions 7 percent below 1990 levels by 2012, a commitment in line with the international Kyoto Protocol.
We didn’t make it.
In 2011, Mayor McGinn pledged Seattle would reach zero net greenhouse-gas emissions by 2050, a promise in line with the Paris Climate Agreement.
We’re not on pace.
Gregoire skirts questions about the tunnel’s climate impact, focusing instead on how removing the massive overhead highway will transform the waterfront.
“Getting cars off the surface, taking down the viaduct, having an extremely safe and attractive tunnel are all consistent with our values,” she said.