State Senate Bill Intro'd To Replace Viaduct With Deep Bore Tunnel

Matt Rosenberg

Earlier this month, Washington Gov. Chris Gregoire, Seattle Mayor Greg Nickels and King County Executive Ron Sims announced an historic accord to replace the seismically vulnerable Alaskan Way Viaduct on SR 99 along the downtown Seattle waterfront with an inland deep bored tunnel. (The last page of this state summary provides details on all project components and planned funding - the tunnel is expected to cost between $1.2 and $2.2 billion). State legislative approval is required. Now, Washington State Senate Majority Caucus Chair Ed Murray, State Senate Transportation Committee Chair Mary Margaret Haugen (pictured, right), the committee's Ranking Minority Member Dan Swecker, and committee member Fred Jarrett of Mercer Island have introduced Senate Bill 5768 to get the tunnel built. The bill will soon get a committee hearing, and if it clears the full Senate will require passage by the House and final approval by the Governor.

Several other legislators have already gone so far as to publish blog posts expressing their support for the Gregoire-Nickels-Sims tunnel plan. They include State Sen. Jeanne Kohl-Welles and State Rep. Reuven Carlyle, State Sen. Joe McDermott, and State Rep. Ross Hunter. More on the tunnel's supporters - and one very important potential backer - in Olympia from C.R. Douglas in today's Crosscut. Members of the King County Council and Seattle City Council and a broad coalition of business, labor, neighborhood and some environmental groups also back the tunnel plan. The current Senate bill could be amended in either chamber, of course, but as introduced it would:

One possible scenario, tolling parallel Interstate 5 through central Seattle, would help minimize diversion, raising additional revenues toward the $2 billion in needed I-5 work identified by WSDOT, and establishing the concept of north-south corridor tolling in west-central Puget Sound. In terms of an evolving regional policy, this could dovetail with a pending option to establish east-west corridor tolling on the State Route 520 and Interstate 90 floating bridges connecting Seattle and the booming Eastside, across Lake Washington.

Tolling of some sort is all but certain to be approved by the legislature on at least the SR 520 bridge as a condition of a federal grant to help fund a multi-billion replacement of the wind- and earthquake-prone structure.

A special SR 520 tolling implementation committee created by the legislature yesterday issued its final report to lawmakers. The committee found broad public support for time-variable electronic tolling on the SR 520 bridge and majority support in the region for such tolling on the I-90 bridge as well. According to the report there is potential to raise as much as $2.4 billion for the SR 520 bridge replacement through tolling both bridges. That's approximately 40 to 50 percent of the total bridge replacement cost.

The report also notes that peak-hour tolling on the SR 520 bridge could improve average speeds from the current 20 miles per hour to 38 mph. Improved peak-hour speeds on the SR 520 bridge are predicted because, given time-variable tolling, an estimated 24 percent of drivers would then either shift to less costly off-peak periods (six percent), transit (three percent), ride-sharing (one percent) - or they would change routes (nine percent spread over three alternates), or destination (five percent).

The projected aggregate shift away of one-quarter of peak-hour drivers following implementation of time-variable tolling on the SR 520 bridge is significant. So are the three-quarters of peak-hour bridge drivers who would not alter their patterns. We cannot wish or hector them into their homes, buses, or ride-share vehicles, nor force their employers to expand tele-work policies.

But further change can be induced through funding increased peak-hour transit frequency in key highway corridors with a full-on system of tolled express lanes, using express buses augmented with pre-boarding automatic pay stations, ground-level entrances and exits, real-time arrival information kiosks, and on-board WiFi connections to the Internet. That last part will prove a huge draw, prompting employers concerned with productivity and costs to more easily see their way to subsidizing large numbers of yearly transit passes for workers.

Accompanying all this must be performance-based measures of improved transit travel times and better inter-modal connectivity, especially for "last mile" travel to work or commercial hubs.

Tele-work will need to grow through employer education, expanded government-funded pilot programs to measure benefits, and perhaps then modest tax incentives.

Another objective is continued development of on-the-fly ride-sharing facilitated by networked communications, one of several big ideas discussed by Microsoft's Chief Environmental Strategist Rob Bernard (TVW video with full transcript at page's bottom, here) during our Cascadia Center's jam-packed September, 2008 "Transforming Transportation" conference in Redmond.

The key conclusions from the SR 520 committee's report are that to manage peak-hour traffic congestion, scarce highway capacity should be rationally allocated through time-variable tolling; and that policy-makers must continue their important efforts - including electronic time-variable tolling - to ensure travelers can select from a robust menu of mobility choices. This pertains not only to Central Puget Sound, but also to heavily-travelled highway corridors in Clark County, Wash./metro Portland, and Spokane .

The unfolding actions to toll the SR 520/I-90 bridge corridor; and to toll the SR 99 tunnel, perhaps ultimately paired with central Seattle I-5 tolling; present a golden opportunity for the state legislature and Gov. Gregoire to continue carving their own broader environmental and economic legacy in 21st Century surface transportation.