Dude, Where Are My Cars: I-405

Through central Bellevue, traffic on I-405 has been flat for a decade.
This post is 29 in the series: Dude, Where Are My Cars?

OK, so we’ve already documented that total vehicle travel—as measured both by traffic volumes on specific segments of the roadway, and by total miles logged on the state highways—has remained roughly flat in much of Washington State for most of the past decade.  Yes, there have been ups and downs, but car travel simply isn’t growing the way it used to.

So at risk of beating a dead horse, here’s a chart of average daily traffic on I-405 through Kirkland and Bellevue, WA. And in case you were wondering…yep, traffic is flat!

It is true, however, that traffic volumes at the north and south ends of I-405 have continued to grow in recent years, at least a bit. And the decline in Bellevue back between 2001 and 2002 looks a little sketchy—was it real, or a data anomaly? Regardless, the recent traffic trends through the most densely populated areas east of Lake Washington look a lot like the traffic trends through the center of Seattle: a bumpy plateau, rather than the steady, uninterrupted ascent that traffic models typically predict.

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  1. Paul Birkeland says:

    Clark – This little series of yours is turning into a damning indictment of WSDOT and other auto advocacy groups. Really very nice work you’ve done.

    Notably, Congress just reauthorized the budget for transportation across the country. The final bill appears to have eliminated funding for infrastructure maintenance, but is larded up with funding for … wait for it … new highways!

    Here's where I get stuck: Who is the constituency that will be motivated by your findings to push for change? It seems like it would be "everyone" since money not spent on highways can go for other things. But the "everyone" constituency is notoriously apathetic.

    Who do you think it is?

  2. Elaine Livengood says:

    “Flat” traffic through Bellevue and Kirkland perhaps, but what a daily mess in the “S” curves! Would have been an idea if the railroad line along Lake Washington could have been utilized for commuter traffic. But of course the upscale dwellers along that corridor would never allow such a thing.

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