We previously reported that Sound Transit is in the early stages of its North Corridor Alternative Analysis. In October Sound Transit held a series of public meetings to solicited public comment on the alternatives. At the time Sound Transit was looking at three corridors, I-5, SR-99 and 15th Ave NE, which I outlined here. ST was just awarded $2 million from the FTA to finance the study.
On December 16th Matt Shelden gave the ST Board a briefing (starting at minute 27:00) on the progress of the Alternative Analysis (lots of other good info in the video too). I think the slideshow above from that meeting or better yet video, speaks for its self but some highlights are below the jump. No action was taken but barring unforeseen events this recommendations will probably be approved by the board. The capital committee will discuss the recommendations during their January meeting.
Highlights after the jump.
- Transportation System Management (TSM) alternative. This is essentially a minor-capital, improved bus service alternative.
- Two Bus Rapid Transit (BRT) alternatives were forwarded
- I-5 based trunk route with direct access ramps and expanded P&Rs (B-1).
- Three branch, I-5, SR-99 and 15th Ave BRT alternative (B-2) with less capital expenses and use of Swift/RapidRide facilities on SR-99.
- Two I-5 Link alternatives, one elevated (L1E) and the other “mixed profile” (L1?). My understanding of mixed profile is an alignment that become elevated where necessary but is otherwise designed to be at-grade.
- Two SR-99 Link alternatives, one elevated (L2E) and the other mixed profile (L2?).
- All 15th Ave NE alignments (L3E and L3G) were eliminated. This isn’t a surprise. The corridor didn’t have much public support and the character of the corridor isn’t very compatible.
- A SR-99 “pure” at grade alignment (L2G) was eliminated. I’m reading “pure” as in Rainier Valley type at-grade running which limits running speed and thus harms time competitiveness.
- Slide 15 has a qualitative comparison of the alternatives. I’m confused how the three branch BRT alternatives has the best land use and economic development compatibility score. Also a few of the labels are missing.
- A map on slide 11 shows that ST will look at both an SR-99 and Interurban alignment for Link.
- Map also shows that ST will look at four different ways for an SR-99 Link alignment to return to I-5, via NW 205th, Interurban ROW, 208th St SW, and 200th St Sw. See map on slide 11.
- Slide 18 and 19 have a rough timeline going forward.