While agreeing with almost all of Ben’s post on 520, I’d like to make a subtle distinction about what I think should happen, as opposed to what will.
I agree that it is extremely unlikely the State will modify the bridge to easily accommodate light rail, as that would cost more than $400m and introduce some project delay. I agree that 520 is not a particularly high priority for rail and probably isn’t even in the cards for ST3. And I agree that in the abstract a Sand Point/Kirkland alignment is superior to one over 520, although I’d add several more shades of uncertainty on that point in the absence of any serious engineering analysis on either corridor.
Given that uncertainty, it would certainly be nice if we preserved the option of going over 520. The question is how much that is worth. I’ll leave comment on how McGinn is or is not damaging his relationship with Olympia to the political hacks. From a pure resource-allocation perspective, it’s really a question of where the hundreds of millions come from, and how much of it must be done during the bridge’s construction.
If it comes from the gas tax kitty for the bridge, then that’s great; taking gas tax revenue reduces the pernicious things the State can do with it. If it’s coming from somewhere else (a TBD, tolling, or anything else that could be used for transit) I’d agree with Ben that there are other priorities that are more important on both the East and West side, especially since we may not need that investment after all. Similarly, if most of the required changes can be deferred to the moment of rail construction, and the immediate needs are relatively inexpensive, then the core objection that the bridge is not rail-ready is a stronger one.
I don’t think Mayor McGinn’s planning has advanced to the point of seriously looking at immediate costs and revenue sources, but they are crucial to the validity of his points.