STA bus route fracas in Browne’s Addition

In a recent Spokesman Review article, it said how a group of residents in Browne’s addition are up in arms about some bus route shuffling STA recently put in place. It made me think of some work I did while with the City of Spokane regarding the real impact that STA buses have on our city streets — particulary residential ones. I wonder if STA and the city talked about the ramifications with the route adjustments? A paper I wrote on the subject quantified those effects. You can find it here: http://www.inlandrail.org/documents/FactPaperForHeavyAxleLoads.pdf

2 Responses to “STA bus route fracas in Browne’s Addition”

  1. Rail Lover says:

    Very interesting article. Thanks for that. I’m no engineer so I have not a clue, so maybe you can lend some expertise on this issue. If buses are going to be running anyway, would it be better to concentrate them on a few streets for more frequent repair or should they be spread out over many city streets that would need more repair but less frequently? Also, aside from using concrete as opposed to asphalt in some places, are arterials designed to withstand more trips than side-streets? Also, how much does Spokane’s weather play into the destruction of streets? Many cities across the country have many many many more buses and trucks on them and they get by somehow. Thanks for this, keep up the good fight!

    • Richard Raymond says:

      Your questions are quite good. Unfortunately, the answers are not straightforward.

      The purpose of my paper was not to speculate so much on the internal decision making process the local transit authority invokes when choosing a route, but more on what I believe to be fact: that route efficiency and adjustment decision making historically has taken NO account of the damaging effects of the bus traffic on the roadway structure. That is, “For thus and so operational reasons, it’ll be better if we move this route over here. Next.” Meanwhile, not only is the abandoned route used up, but another route will now be adversely impacted, all apparently without any thought process–or concern, for that matter–as to how these deleterious structural effects can and should be mitigated.

      The bottom line is that the citizens end up subsidizing the transportation system when the city’s street program is tapped to repair the damage. This should not be a shock–one way or the other (state and federal grants; local taxes) the citizens already are subsidizing the normal transit system operations probably to the tune of 75% or more. We’re not unique in this characteristic, by the way.

      All this having been said, I believe that the local transit system MUST have the ability and agility to adjust routes. After all, they are providing a much needed service that certainly, at least to some extent needs to be responsive to the customers’ needs, moderated as it must by the fact that it is highly subsidized. Additionally, the local transit system will play a vital role in the viability of any overall regional transportation system. It’s just that when making the route decisions, I would hope for ALL factors to be considered.

      Now, specifically to your questions. Regarding concentrated routes or more spread out routes: Beats me! I would think that a whole bunch of small, much lighter transit vehicles (I purposely did not say, “busses”) spread out over numerous routes would inflict the least amount of damage, given the intrinsic reserve structural capacity (albeit limited) of our residential streets. This, however would certainly not be in the cards for at least one very obvious reason: each vehicle would require a driver, and the payroll cost would literally go out of sight. If the busses could be restricted to the arterial system, the busses still would probably inflict the higher percentage of pavement deterioration–except, of course with the heavily use primary truck routes–but the marginal cost for “hardening” the pavement structure (increasing its structural capacity) to accommodate the busses themselves, when compared to the other car and truck traffic would I suspect be fairly minor when figured over the life of the pavement. However, I would think that restricting the busses solely to arterials would not be practical. After all, the whole idea is to make riding a bus an attractive option, and if I remember correctly the city’s arterial system is supposedly based on a one mile grid spacing. Ultimately, staying with the existing model may be the “least bad” solution, but with certain caveats: (1) upgrade the structural capacity of the streets on the residential bus routes when they come up for repair, using transit funds to finance the marginal upgrade cost which, in some cases might even come close to the “basic” cost of a “standard” residential street; (2) account for the true route-related pavement deterioration costs in the transit system budget, so that when future street replacement is needed, or when route changes are being contemplated, the TRUE cost of doing business is taken into account.

      Regarding the design of arterial versus residential streets: Yes, arterials are designed to withstand more trips than residential streets. The usual analysis period (note that I did not say “design life”) for a street is 20 years–oftentimes more. Residential traffic is much, much less than arterial traffic, so over the course of identical analysis periods, an arterial will receive a lot more traffic than a residential street. Historically, the structural “design” of roadways in the City of Spokane were, in fact the result of a “cookie cutter” approach–streets on the north side (where there was predominantly sand were one section and streets south of the river were a bit heavier (higher preponderance of clay and silt). Consequently, there were more failures than probably should have been. However, within the last twenty years, that paradigm has fortunately gone by the wayside. Now, the design section uses industry-accepted design methods to design the streets. These methods take into account soil conditions, regional climatological patterns, available construction materials, and traffic patterns (frequency and weights of the anticipated traffic mixes). Due to their low design trip count, most residential street pavement sections are lighter–often governed merely by the city’s “minimum” design section. Arterials typically receive MUCH higher and heavier traffic than residential streets and thus typically present quite a bit heavier (thicker) pavement section.

      Regarding the weather’s role: the weather plays a HUGE role over a pavement’s life. Sunlight (specifically ultraviolet light), is a bad actor, but so are the extreme heat, cold and freeze/thaw cycles. In our region, the freeze/thaw cycle is a particularly bad actor when it comes to pavement longevity.

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