The environmental case against the waterfront tunnel for Seattle

Six prominent environmentalists argue against the proposed deep-bore tunnel under downtown Seattle. They maintain that a streets/transit/I-5 solution creates more jobs, addresses our mobility needs more quickly and cheaply, and sets us on the path to a livable, post-carbon future.

Crosscut archive image.

A visualization of the central waterfront, sans Viaduct.

Six prominent environmentalists argue against the proposed deep-bore tunnel under downtown Seattle. They maintain that a streets/transit/I-5 solution creates more jobs, addresses our mobility needs more quickly and cheaply, and sets us on the path to a livable, post-carbon future.

Four of our friends and environmental colleagues recently made a case for tunneling under downtown Seattle to replace the Alaskan Way Viaduct. They, along with many of our friends in the labor and business communities, have concluded that the tunnel is the only viable path forward. It pains us to disagree, because we respect them and value the relationships and accomplishments that our work together has brought.

As a citywide vote on the deep-bore tunnel approaches, however, we cannot remain silent. Like many, we are frustrated by the seemingly endless delays and squabbles that have surrounded this issue. We empathize with the cries to “Just do something! Anything!” But we can’t go along with that “anything” when the chosen path—the deep-bore tunnel—is demonstrably inferior to the leading alternative.

The advantages of the package of smart investments called streets/transit/I-5 (“ST5”) are overwhelming. Compared with the tunnel, ST5 creates construction jobs for local workers more quickly, improves traffic flow downtown, yields the same beautiful waterfront, is faster to build, aligns with our civic values and climate goals, and saves us about $1 billion.

The new, 7,351-page Environmental Impact Statement gets us past the claims and counterclaims with a comprehensive analysis that clearly shows the tunnel’s failings. It shows, for example, that the tolled tunnel will put almost as much traffic on the streets of downtown Seattle as would just closing the viaduct and walking away. Repeat: spending billions on a tolled tunnel is barely better for downtown streets than letting the viaduct fall down.

By comparison, the major elements of the ST5 plan are straightforward and workable: reconfiguring I-5 ramps and restriping the freeway to add a new northbound lane in the existing right of way; wiring I-5 with smart traffic-flow management signs; adding transit service in key corridors; opening new freight and passenger capacity by removing bottlenecks in the existing street grid, especially at the north and south ends of downtown; and upgrading the infrastructure for walking and cycling.

ST5 developed over years, in city agencies and community meetings. In 2008, it emerged a winner from the joint decision-making process convened by the city, county, and state after city voters famously rejected both the elevated viaduct rebuild and the cut-and-cover tunnel. But the state pushed ahead with the deep-bore tunnel. At the time, the tunnel wasn’t much more than a napkin sketch with no known price tag. Perhaps without benefit of analysis, it seemed like a reasonable compromise. Now we know better.

ST5’s targeted, smart, decentralized investments deliver better mobility, according to several different analyses (editor's note: separate links for the studies are here, here, here, here, and here), and do it for just three quarters of the cost. ST5 puts fewer cars on downtown streets than the tolled tunnel and improves their flow, while eliminating traffic bottlenecks and prioritizing access for transit and freight. It also creates construction jobs for local workers more quickly than does the tunnel, because it’s easier to stage lots of small projects than one underground behemoth. ST5 is fairer to working families, because it expands transit service and avoids the pocketbook pinch of $5 tolls.

ST5’s pragmatic approach to simple, low-risk transportation investments is among its key virtues. Some $300-$700 million of tunnel funding is still not secured, and already, before the design and planning are done, escalating costs have eaten deeply into the state’s contingency fund. There’s a grave risk that the tunnel will cost more than budgeted, as do most tunnel projects near and far. As just one example, tunneling failure is a real danger. The tunnel will be dug by a 56-foot-wide boring machine with no reverse gear that can only be removed vertically, that is, up through a massive hole in downtown. Unlikely? Two of the tunneling machines working on King County’s Brightwater sewage treatment plant have broken down, triggering layoffs of more than 100 workers during repairs.

The tunnel has no financial guarantor, just an ongoing dispute between city and state about who must pay cost overruns. This situation ought to give Seattleites dry mouth, because state law assigns the bill for all tunnel overruns to city tax payers. Key state legislators are bound and determined to make sure that Seattle residents pick up what could be a blank check for a money pit.

Tunnel advocates argue that creating a spectacular waterfront requires putting traffic underground. We share their excitement for the waterfront vision. Indeed, many of us have devoted years to developing and fighting for it. The tunnel, however, is not essential to that vision. ST5 can deliver exactly the same waterfront design as the tunnel: the same four-lane Alaskan Way, the same parks and bike paths, the same reintegration of city and bay, and – above all – the same eradication of the elevated highway that has blighted our shoreline for half a century and more. The state’s Environmental Impact Statement predicts traffic on the central waterfront with a tolled tunnel or with a viaduct that’s suddenly closed. The difference in car numbers? Two percent or less. Other studies show a similar range of traffic outcomes (links: here and here) on the waterfront. The main lesson, however, is that traffic choosing Alaskan Way will be the result of city decisions about the roadway’s design and lane width, not state decisions about the tunnel.

At the end of the day, this multi-billion dollar project isn’t just about our waterfront or downtown traffic flow. It’s about our city’s future and identity.

At our best, we in Seattle invent new solutions that others copy, from airplanes to online retailing; we pioneer decentralized, green solutions that set an example for the world.

Three decades ago, Seattle said “No!” to WPPSS’ nuclear power, instead making ourselves world leaders in energy efficiency in our homes, offices, and factories. Two decades ago, we said “No!” to a massive burner to incinerate our garbage and showed the country how to make every kitchen and workplace a recycling center. One decade ago, after the California electricity crisis, we said “No!” to coal and natural gas plants; we turned to the wind and, again, efficiency. In fact, we made City Light the country’s premier carbon-neutral utility. We’ve also made some big mistakes. Four decades ago, for example, we turned our backs on federal transit funding that would have given us, by now, a world class light-rail system.

We now confront another pivotal decision.

ST5 not only delivers better transportation more cheaply, it also speeds us along the path to a livable, post-carbon future. Seattle is a leader for sustainable prosperity: a way of living well and durably on our only planet. We are moving toward that vision -- in fits and starts, yes, and often too slowly. Still, we are moving forward. Building a bypass freeway downtown would be a lurch backward, undercutting much of the progress we’ve made. Spending billions to bury it would do little to hide that tragic reversal.

We’ve already begun breaking our oil addiction by investing in new mass transit, calming traffic, and making room for bikes on our roadways. Block by block, we’re rebuilding our city, transforming our neighborhoods into complete, compact communities. Already, we’re driving less. Per-capita gasoline consumption has dropped since 1998 to the levels of the late 1960s, and traffic on Seattle’s freeways has been flat or declining for eight years or more. It’s a good—no, a great start! We are poised to step into the ranks of the world’s most innovative cities: places from Seoul to San Francisco that have demolished urban highways (links: here, here, here, and here) and replaced them with transit, better street connections, and thriving neighborhoods.

Some proponents candidly acknowledge the tunnel’s drawbacks. They support it because they feel the need to do something, and they see the tunnel as the only politically viable path. That is self-fulfilling defeatism. What our community needs now, in these dark economic and political times, is a brave and pragmatic, “Hell, yes! We can do better than a buried highway.”

Join us in rejecting the tunnel, by rejecting Referendum 1 on Aug. 16.


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