(ADDED 6:52 PM: Full presentation with evaluation information on all 4 segments, West Seattle at end)

By Tracy Record
West Seattle Blog editor

5:30 PM: Just past the halfway point in the process of coming up with a “preferred alternative” for the West Seattle and Ballard light-rail extension, Sound Transit has just gone public with an avalanche of evaluation information about the options on the table.

The information is being presented to the project’s Stakeholder Advisory Group at the ST board room downtown. We were invited to an advance media briefing this afternoon, with the details embargoed until the SAG briefing began for this meeting.

Three of the five potential routes that are in the second of three phases of review involve tunnels – and the newly released evaluation information makes it clear that tunneling will cost extra money and time.

The document’s not online yet but we have a paper copy and are starting with a few highlights:

The documents are densely packed, evaluating the alternatives on hundreds of points. Cost-wise, ST says the Pigeon Ridge/West Seattle Tunnel alternative would be $1.2 billion more than the originally drafted “representative” project; the Golf Course/Alaska Junction Tunnel alternative would be $700 million more; the Oregon Street/Alaska Junction Tunnel alternative would be $500 million more. Those all would require “third-party funding” to cover the tab, ST says. And while specific time wasn’t cited, the agency says adding tunneling would “affect the schedule” – meaning it would take longer than the 2030 opening goal.

Also from the document, while we wait for a digital version in its entirety (we’ll add it when it’s available added above at 6:52 pm), here are the ST-provided overviews of what differentiates the alternatives:

The above “Duwamish Crossing” differentiating factors refer to the alternatives for getting the light-rail route across the Duwamish River on a new bridge. Also of note above – when you see “low guideway,” that means no higher than 60′ tall; “high guideway” could be up to 160′ tall.

Next, the overview on differentiating factors between possible locations for the three West Seattle stations:

Again, the Stakeholder Advisory Group is being briefed on all this – plus the fine points – for the West Seattle segment, SODO segment, Downtown segment, and Ballard segment of the light-rail extension project. Its members are not being asked to make their resulting recommendations today on what will advance to the next level, but will be asked to do that at their next meeting on September 26th. In the meantime, the next public touchstone in the process is Saturday (September 8th) at the West Seattle neighborhood forum, 9-11:30 am at the Seattle Lutheran High School gym (4100 SW Genesee).

The briefing here at the meeting has started with the Ballard segment and is working its way south; we’ll add to this story when the discussion gets to the West Seattle segment.

6:52 PM: They’re not at West Seattle yet – but it’s coming up after 7:15. Meantime, we’ve received the full PDF with all the evaluation points on all four segments, 113 pages, and you can see it above, or here (10 MB PDF). It’s not yet on the ST website.

7:15 PM: And now, the West Seattle briefing. ST’s Stephen Mak is leading it. It begins on page 87 of the full presentation (now added atop this story, with a PDF link in the paragraph above this one). Note that when it gets to the grids, red means an alternative performs “low” on that datapoint; beige, “medium”; green, “high” performing.

Among the many datapoints are environmental effects; ST singles out the Pigeon RidgeWest Seattle Tunnel option as having a major effect on the (West) Duwamish Greenbelt forest, essentially bisecting it at one spot, they say. The Junction alternatives’ datapoints include concerns about potential for future extension of the light-rail line – where exactly it ends will make a difference in that. (The Golf Course/Alaska Junction/Tunnel alternative is described as best accommodating future light-rail extension beyond West Seattle.) Mak’s briefing is moving quickly now that the meeting is approaching its final half-hour, so by reading the pages above, you’re in essence getting the same thing. The summary page is 106, mentioning all of the key points – cost differences, schedule, differentiators.

7:31 PM: Sloan Dawson, who works on station-related planning, is discussing the results of the charrettes that discussed station possibilities. The Delridge group, he said, preferred the “Genesee Elevated” option. The “West Side Delridge” option might have overwhelming height and bulk, he noted; the 25th SW Elevated option would put the station in the middle of a current single-family-house neighborhood. One group member asked if the cost estimates included more than just building the route and station – did it include other potential features? The answer to that: No.

The Avalon options, which were coupled in a daylong charrette with Junction options, didn’t have a clear favorite. And on to Junction station options: Putting one at Fauntleroy was seen as too distant from the business district; the one with the most potential, at 42nd/41st, especially as a connection in a network that could run between California and Fauntleroy.

We’re listening in on one group which among other things is wondering about effects on the port if the crossing of the Duwamish is routed north of the West Seattle Bridge. It would affect T-5 and T-18, says a port rep, who also noted that they’re hoping to announce a new T-5 tenant by the end of the year. The group also wondered about mixing and matching parts of existing alternatives – ST has said previously that

“This next three weeks is going to be critical for reviewing” all the new information, the Stakeholder Advisory Group was told in summation. And apparently there’s even more information beyond what’s in the presentation we posted above, so we’ll be checking into that too – they include new ST-produced visualizations and those will be available online, ST just said (though they weren’t shown at this meeting). Again, September 26 is the next meeting for this group, at which they’ll recommend what they want to see move forward; that recommendation then goes to the Elected Leadership Group on October 5th.

But before then – if you care about where this is going (and if you read this far, you probably do), don’t miss Saturday morning’s West Seattle “forum.”