After a public records request, numerous phone calls, and a trip down to Sound Transit's Union Station headquarters, the Trans-Lake study has finally been released to The Stranger. Unfortunately, Sound Transit press officer Lee Somerstein barred us from interviewing any Sound Transit employees about the report. That's okay; the study speaks for itself.
The official title of the study is "The Technical Memorandum: Deployment Scenario Development, Trans-Lake Deployment Scenario." The 36-page document, written by Kansas City-based engineering company Bucher, Willis & Ratliff (BWR), is an assessment of the types of transit technologies that could safely make it across Lake Washington. BWR felt, and pointed out in their report's executive summary, that getting across the lake presents a variety of challenges.
The main challenge, after identifying a floating bridge as the only possible bridge for a Trans-Lake transit system, was finding the safest transit technology. BWR made it clear that "[v]ehicles under consideration for deployment on a floating bridge must accommodate the motion of the bridge structure caused by wind, water currents, and tidal fluctuations." To BWR, the 520 and I-90 floating bridges take a lot of abuse from the elements, and any mode of transportation must be able to withstand that abuse. On this basis, light rail was disqualified.
The report says, "Due to the motion and movement of the floating bridge, light rail track guideway vehicles were not recommended." (As The Stranger reported earlier, sources close to BWR, as well as engineers like Jim MacIsaac and Paul Larrousse, a Sound Transit expert review panel member, cautioned that keeping a light rail train on its two-inch-wide steel track over a floating bridge is problematic.) The study confirms that BWR engineers felt "Fixed Track light rail and other forms of ATT (Alternative Transit Technology) requiring a rigid support structure will encounter safety problems...." After BWR panned light rail, they offered important advice to Sound Transit. Unfortunately for Sound Transit, the advice calls into question the entire light-rail regional plan.
BWR insisted that whatever transit technology is implemented across the lake should be used consistently over the entire system. Since BWR recommended against light rail across the bridges, they questioned the use of light rail systemwide. "Segmenting transportation into Trans-Lake and all other transit in the Puget Sound Region would be highly inefficient and likely very ineffective," BWR wrote. This is a torpedo to Sound Transit's regional plan--specifically Phase 2 of the plan, which involves light rail on the Eastside. The report continues, "An integrated system, utilizing the same vehicle technology, would enable passengers to board the transit system... throughout the region and travel seamlessly, including across Lake Washington, to a desired destination." In a nutshell, don't switch up transit options, or people won't ride it. Citing "contract disputes," Sound Transit fired BWR before their report was finalized.
Sound Transit insists light rail is safe for the floating bridges. They cite a September 13 Washington State Department of Transportation report that says with the right modifications to I-90, especially on the joints that connect the floating section of the bridge with the fixed section, light rail transit is doable. Sound Transit also cites two bridges, one in Vancouver, BC, and one in Lisbon, Portugal, that have similar joints and have operated without problems. Neither of those bridges are floating bridges, however. Sound Transit government relations spokesperson Mauri Moore also questioned the validity of BWR's Trans-Lake study, insisting that The Stranger should have a transportation "expert" review the study. (Evidently, when Sound Transit hired BWR last year to do transportation consulting, they didn't feel BWR was an expert.)
BWR would not comment in detail about being fired or about their Trans-Lake study, but BWR executive vice-president Steve Lewis does stick by his company's report. "We completely stand behind our draft study, and that was our opinion at the time," says Lewis, referring to his company's early departure from the Sound Transit contract.
