As the Bellevue City Council begins to accept that light rail will run down Bellevue Way and 112th Ave SE, the focus of negotiations is turning to mitigation of the neighborhood impacts. The biggest one is associated with the three at-grade crossings that exist in the preferred “B2M” alignment. There are two street crossings at SE 4th St and SE 8th St; these have bells and crossing gates, disruptive to cars and pedestrians as well as generating noise for safety signals. Where light rail will cross from the east side to the west side of 112th Ave, there is a traffic light and warning bells.
In response to these concerns, Sound Transit came up with revisions to eliminate all the at-grade crossings. The crossing of 112th will move down to SE 15th St and use a flyover, eliminating the at-grade crossing of 112th and also no longer crossing SE 8th at all. At SE 4th, Link will dip into a retained cut, eliminating traffic conflicts. If there’s a tunnel through downtown the stop at SE 8th will have to move to a below-ground location near Main St.
According to ST spokesman Geoff Patrick, this will have the salutary side effect of making the entire East Link alignment grade-separated from the Downtown Seattle Transit Tunnel to as far as Hospital Station if the downtown tunnel is built. Due to some curves in the track, trains will average around 45 mph through the B segment, but will exceed the street speed limit. It also means that trains in this segment are only limited in frequency by sharing space in the DSTT with Rainier Valley trains, rather than by the limitations of at-grade signaling.
The bad news is that this will add to project cost, although ST staff hasn’t worked out the precise numbers yet. This aggravates the value engineering that ST is already doing to match costs to revenues. These changes may be approved at the July 28th Sound Transit board meeting.