In 2016, when the Alaskan Way Viaduct is closed and demolition begins, King County Metro will lose its primary conduit into downtown Seattle from West Seattle and southwest King County. While all post-Viaduct pathways will be significantly slower and less reliable, the agency has to figure out the best replacement according to some combination of speed, reliability, access to the city center, and ease of operation. After eliminating options deemed unworkable, the choice basically boiled down to variations on two themes: a waterfront pathway, following the surface Alaskan Way to Colman dock, then up the hill to 3rd Ave via some combination of Marion and Columbia; and a Pioneer Square pathway on some combination of Main and Washington.
As announced on the Metro Future Blog last week, the agency is proposing a two-way configuration on Columbia Street. Beyond the announcement, Metro has quite a bit of information up about the decision. There are some easily-digestible nuggets also on Metro Future about the pathways not chosen and likewise in this fact sheet, and a report which comprehensively analyses the four final alternatives. To get right to the bottom line, skip to PDF pages 67-69 for a tabular summary of the results. As far as I can tell, the report seems thorough and well written, with reasonable conclusions.
I’ve said my piece on this already, but for posterity: the two-way Main St pathway, pictured above, would have provided by far the best intermodal connectivity and access to the south end of downtown, and been almost immune from ferry traffic congestion, all for the ongoing cost of about a minute in travel time inbound, and three minutes outbound. The pathway would have been significantly more expensive to implement — Main Street completely rebuilt with wider sidewalks, custom paving and bus shelters — but it could have become a beautiful and functional gateway to one of the few truly urban places in Seattle, and provided year-round activation to the often-forlorn Occidental Mall. By contrast, Columbia is nothing more than a pipe for cars.
Unfortunately, the people with the most to gain from a Pioneer Square alignment fought the hardest against it, and when I discussed the alternatives with Metro staff some months ago, it was made clear that whatever the technical merits of this pathway, well-connected anti-bus NIMBYs had foreclosed that possibility; a Columbia pathway was almost a foregone conclusion. The question now is whether Seattle will give Metro the transit priority treatments needed to get buses reliably through the mess at Colman Dock.