Southwest Corridor Questionnaire

This past Thursday, May 23rd, a community planning forum was held to present and discuss the current status of the SW Corridor, and solicit more community input. For those who didn’t attend, the materials have been posted on the project’s home page, and there is an online questionnaire for those who wish to add their two cents on the project.

Of some interest was this set of slides showing trade-offs of different routings, and this slide, giving preliminary cost and ridership estimates for different variations of the corridor. The relevant details are repeated after the jump:
The numbers

Capital costs:

  • OHSU tunnel: $3.1B
  • LRT to Tigard: $1.7B
  • LRT to Tigard and Tualatin: $2.6B
  • “Best performing BRT”: 50%-80% of LRT ($850M-$1.36B to Tigard, $1.3-$2.1B to Tualatin)
  • “Mid performing BRT”: 40%-50% of LRT ($680M-$850M to Tigard, $1.0B-1.3B to Tualatin)
  • “Lower-performing BRT”: < 40% of LRT


  • LRT to Tigard: 22.5k
  • BRT to Tigard: 20.1k
  • BRT to Tualatin: 26.9k
  • BRT to Sherwood (via Tigard and Tualatin): 28.9k

Operating cost/year:

  • LRT to Tigard: $4.9M
  • BRT to Tigard: $6.3M
  • BRT to Tualatin: $7.5M
  • BRT to Sherwood: $10.1M

A few caveats on the numbers:

  • It is unclear whether the $3.1B for a tunnel is instead of a surface route, or in addition to it.
  • Ridership and operating cost for other scenarios not listed, has not been modelled.
  • I believe that ridership and op cost figures are the costs and ridership of the new service, and don’t take into affect changes to other services. (In other words, the ridership figures don’t appear to be all new riders, and some operational savings may be had from reducing redundant local service).
  • Route to Sherwood is via Tualatin; a King City routing appears to be out of the picture at this point.
  • A line to Tigard would terminate at Tigard TC; it is unclear where a Tualatin extension would end (the two logical places would be at Tualatin Station and at Meridian Park Hospital).


The immediate thought is that the capital costs, particularly for light rail or high-end BRT, are high. The distance between PSU and Tigard TC, with deviations to the Tigard Triangle and PCC-Sylvania, is about 10 miles, so the cost-per-mile for a surface LRT solution is actually a bit lower than PMLR. The West Hills cannot be an easy place to put a transit line–on the other hand, there’s no major bridge needed for this project (an extension to Tualatin may need a new crossing of the Tualatin River, but that’s far less of a big deal than a crossing of the Willamette. The distance of a route to Tualatin is nearly 15 miles. Assuming a higher-end BRT can be done for 2/3 the price, one could reach Tualatin for the same budget as LRT to Tigard, and still provide a high quality transit service.

Of course, these are all preliminary numbers; not a budget of the scope and accuracy that one would find in a DEIS or other advanced planning document. Unfortunately, preliminary numbers tend to be on the low side…

BRT would provide a few other opportunities–it supports branching service much better, and it’s easier to phase: Assuming the vehicles used aren’t too exotic, busses on a BRT going to Tigard can continue on surface streets to Tualatin if there isn’t enough funding to go all the way to Tualatin in one go–and likewise to Sherwood. By the same token, it may be possible for the 76 to use a new busway or bus lane between Tigard and Tualatin. (And while this isn’t in the works for the SW Corridor, a BRT between Beaverton, Washington Square, and Tigard is a tempting idea…)

The big question is–where and when will money come from to build anything on the scale of what is discussed above? And the second question–which I’ve asked several times before, but not really seen a satisfactory answer to–why have capital costs for this sort of thing skyrocketed, particularly in comparison to earlier MAX lines?

The floor is open.

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