Dominic Holden asks:
Transit nerds, what do you say? Is light rail [over 520] still unfeasible, totally workable?
Mayor McGinn claims that light rail is still “financially and/or environmentally infeasible”, even after WSDOT’s modifications to “accommodate” light rail. I believe the Mayor is basically correct. However, the modifications have made it somewhat more feasible, and after reading the white paper on the subject, I think the problems are beyond the powers of WSDOT to fix. The reason it is financially infeasible is that no one has a dime to spend on 520 rail. Even a minimal line, from UW station to South Kirkland Park and Ride via Montlake Blvd, would by my rough estimate cost about $800m.*
This is not like I-90, where an entire roadway already designed for rail already exists. On the other hand, WSDOT has at least eliminated the requirement to demolish parts of the span to build rail.
As reported previously, adding rail would require adding supplemental pontoons, which will cost significant money but not otherwise be all that disruptive, except while rails are being installed in the HOV lanes.
WSDOT has to hedge its bets on the cut crossing because no one knows how Sound Transit would attempt this. The four basic options are:
- A high bridge from Foster Island;
- A tunnel from Foster Island;
- Up the HOV ramp and across a third bascule bridge;
- Up the HOV ramp and at-grade on the second bascule bridge.
More obstacles after the jump.
If the train is to use the current HOV off-ramp, WSDOT has done the obvious things (grade and curvature) to accommodate rail, but “additional design work is necessary to determine that the ramps can, in fact, be directly converted to LRT.”
The alternative, leaving the roadway at Foster Island, has “significant environmental implications.” I think that’s code for “you’ll never get this past the lawyers,” but perhaps someone else can spell out those implications. And of course, a whole new crossing will be massively expensive.
There is no guarantee that rail could run over the second bascule bridge:
The design has not encompassed the need to accommodate flush mounted light rail tracks to facilitate a shared roadway surface with motor vehicles. Stray current protection design and adequate clearance for the overhead catenary system (OCS) are also features that must be considered in the design if this crossing alternative is preferred.
Could WSDOT do more? Engineering-wise, they could spend money to better develop one or more of the crossing options, especially to make sure that the Montlake path is a viable one. This might also result in some engineering changes to the offramp and the bridge. Of course, the rail authority might not ultimately approve a Montlake route. Any work beyond that would require outlays in the $100m+ range.
The broader issue, of course, is that there is no rail authority looking at this issue. Seattle, rightly, is focusing on new rail on the west side of the City. Sound Transit is tapped out tax-wise and will be so for decades unless there’s a miracle in the legislature. It would be great if WSDOT brought money to the rail building game, but in this universe I think it’s best to focus our political firepower on bus access issues, which I’ll discuss in my next post.
* The distance is 5.8 miles. The A segment of East Link is $109m/mile, plus about $150-200m for more pontoons. This all assumes the issues with the Montlake alignment described above are not costly to address.