We are in deep Viaduct

The project team's two final alternatives give the city a choice between two bad options, neither of which is likely to survive challenges. There's a better way, according to this advocate for the deep-bored inland tunnel.
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The Alaskan Way Viaduct in Seattle.

The project team's two final alternatives give the city a choice between two bad options, neither of which is likely to survive challenges. There's a better way, according to this advocate for the deep-bored inland tunnel.

The state-led waterfront project team has told Seattle it must choose between erection of a new, even wider Alaskan Way Viaduct, or (what's called the 'ꀜall surface'ꀝ option) letting city streets absorb a huge stream of trucks and cars that now use the elevated freeway. Some choice.

By ignoring the superior economic, financial, transportation, environmental, and aesthetic benefits of a combined deep-bored tunnel under downtown and a waterfront boulevard for local traffic, the Washington State/King County/Seattle transportation project team has paved the way for a political donnybrook. They should think again.

The reasons are simple. A bored tunnel, surface-transit combination has many supporters and few die-hard detractors. It acknowledges the legitimate environmental and business interests of the alternatives. Unlike a Viaduct replacement, a tunnel can be constructed and opened before the months-long demolition of the existing Viaduct begins, thereby mitigating bad traffic effects. For these reasons, opposition to the tunnel option focuses largely on the mistaken, out-of-date cost estimates of the State Department of Transportation that suppose that any tunnel will be too expensive. Failing to consider up-to-date technology and costs was a serious oversight by the project team.

A new Viaduct would handle the current load of 110,000 vehicles a day and thereby satisfy businesses like Boeing and the Port of Seattle that need to move freight expeditiously. It also would accommodate the travelers who are moving through the west side of the city and not stopping in the downtown. But, generations after other leading cities liberated their waterfronts from multi-story roadways, a new Viaduct would represent the worst throwback to poor design in the history of the city and qualify Seattle for architectural booby-prizes for years to come. Such short sighted, single-purpose transportation thinking would consign the harborfront to blight and economic stagnation. After literally three decades of criticism of the present Viaduct, the region would inexcusably replicate the error for our posterity.

That assumes, of course, that the monstrosity — once chosen — ever got built. Urban design critics and air pollution foes will hate it actively. Federal money, if any were sought, would likely trigger provisions of the President'ꀙs Advisory Council on Historic Preservation that apply a standard of 'ꀜno feasible alternative'ꀝ to transportation projects. Having once served on that body, I find it hard to see a new Viaduct gaining approval. No elevated highways have passed federal review in such cases since the 1970s. Even before federal action, however, local opponents might well take to the lawsuit route and, then, the initiative process to thwart a new assault on Seattle'ꀙs physical future.

However, the all-surface option will fare little better. Of course it would be wonderful progress to get rid of the unsightly Viaduct and open up water vistas. As mitigation, there are some good ways proposed to improve traffic flow on downtown streets and expand transit use. A new lane squeezed out of I-5 would help, and is needed anyhow. But there is no reason to think such mitigation would begin to suffice in soaking up the existing US 99 traffic flow. It would be an ironic environmental 'ꀜimprovement'ꀝ that resulted in more clogged, polluting traffic tie-ups on the waterfront.

Even before an all-surface outcome is tested in practice, City, County and State will have agitated the already restive business, trade, and labor communities that consider politicians to be insensitive to what is required to make trade and commerce work on a waterfront. And'ꀔjust to rev up the lawsuit and initiative process with real passion'ꀔthe many Seattle area people who merely want to get through the downtown bottleneck as quickly as possible are going to be indignant over the prospect of start and stop, cheek by jowl traffic along Alaska Way.

The project team holds out the alternative of a deep bored tunnel as a stand-alone project that could be considered later once a surface option is adopted (if it is). But this is surely a classic case of 'ꀜkicking the can down the road,'ꀝ waiting until traffic paralysis occurs and then starting a new project'ꀔthat will take several years to implement'ꀔto cure the mess the transportation whizzes will have just created. Corporations and their clients are not going to wait around patiently for the Seattle region to slowly crawl up the transportation learning curve. They could well be gone, with their money, before the surface-only folly is evident.

It is unfortunate that a bored inland tunnel only gained attention in the last couple of years. Most people think that 'ꀜtunnel'ꀝ still refers to a cut and cover trench along the present Viaduct route, as originally proposed some years ago. A bored inland tunnel is a huge improvement over the idea of a trench in every way'ꀔcost, aesthetics, environmental impacts, and construction mitigation.

It is also unfortunate that the State DOT is still using out of date estimates for such a facility and seems to have missed the rapid technological strides that have been made in tunneling in recent years. Had they bothered to look only as far as across town to the Sound Transit tunnel through Beacon Hill that is coming in at $300 million'ꀔon budget and on time'ꀔthey would have been forced back to their calculators. They also seem to have slighted the myriad tunnel projects going in elsewhere in the country and world.

Indeed, the project team has yet to talk with the local and international engineers and planners consulted by Discovery Institute'ꀙs Cascadia Center. These experts have come up with basic estimates of $1.4 to $1.7 billion for an inland tunnel option that would free the waterfront for reasonable car traffic and transit, while carrying freight, more transit and the current through-passenger cars that use the Viaduct. (Note: the Beacon Hill tunnel cost of $300 million is for one mile. The inland tunnel proposed for the waterfront region would be twice as long and twice as wide.) This is well within the budgets that have been discussed heretofore and has long-range savings that the others can'ꀙt touch. A tunnel lasts far longer than a viaduct.

Unlike either option the project team selected to consider further, the bored tunnel alternative would be a prime candidate for federal funding in the 2009-2010 period, lowering local cost burdens even more. Environmental and safety objections would be minimal. The tunnel could recapture and remove car exhaust particulate and keep polluted runoff from entering Puget Sound. It may be counter-intuitive, but a tunnel also would be safer in an earthquake (as the Bart tunnel showed in San Francisco) than a new Viaduct. It would not be affected either by the danger of liquefaction of fill soils that may afflict the waterfront itself during a major quake.

The Alaskan Way Viaduct Stakeholders group that was set up to advise the politicos was not allowed to vote formally this week, but after their long study, 24 of 25 of them made clear informally on Thursday night that they want the bored tunnel and surface boulevard option examined further. That is in the joint economic and environmental interest of the region and therefore, one would think, the political interest of our leaders.


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About the Authors & Contributors

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Bruce Chapman

Bruce Chapman served in several elective and appointed posts in local, state, national and international affairs and founded Discovery Institute.