Friday, June 13, 2014

#165 / As Predicted

What you see here is a picture of Highway One in Santa Cruz County, at the Morrissey Avenue Exit, heading towards Watsonville as of 4:00 p.m. on Tuesday, June 10, 2014. That's just a few days ago. The traffic was barely moving. 

Had you been at this same spot at 4:00 p.m. on June 10, 2011, three years ago, you would have seen virtually the same thing. 

That shouldn't be surprising, right? Same time, same place, same highway; what else would you expect?

Well, you might expect something else if you knew that between 2011 and this year the Santa Cruz County Transportation Commission has spent at least $16 million dollars to add "auxiliary lanes" to Highway One, in exactly this location, with the idea being that this expenditure would improve traffic flow. What this picture illustrates is how the highway is operating today, with those auxiliary lanes. The project is now complete.

Remember, the idea was that these new auxiliary traffic lanes would relieve traffic congestion. How do you think we are doing with that?

Local environmental advocates, and specifically a group called Campaign For Sensible Transportation, strongly opposed the proposed highway widening project, before the Transportation Commission made its final, $16 million dollar commitment. One of the points made by highway widening opponents was that a phenomenon called "induced demand" would result in new cars entering the highway when the project was done, using up any new capacity provided by the project. This is not some weird and wacky environmentalist theory, either. The reality of "induced demand" is well recognized by traffic planning professionals.

So, do you want to widen the highway? You can spend a lot of money. You can cause a lot of air pollution. You can increase the amount of gasoline consumed. But if you want to relieve traffic congestion, highway widening is not going to be your best route to success. The phenomenon of induced demand means that the post-widening traffic congestion will be just the same as traffic congestion before the widening, but with more cars caught in the jam.

In other words, the Highway One Auxiliary Lanes project is working exactly as predicted!

Image Credit: 
Personal Photo


  1. Another excellent example of "If you build it, they will come."

    1. Correct! And not in a good way.

    2. Well, "they" are people and they have to live somewhere. Population of the US is way up. Of course traffic is getting worse.

  2. No surprise there!

    "Planners" are adept at making plans for the past, not for the future. It seems ironic that planning organizations are completely inept at assimilating, understanding and employing new data about the subject of their plans. They are always decades behind the times.

    This seemingly illogical situation is because planners require a constant source of big projects to fund their bloated departments. Hence, Highway 1 widening and Broadway-Brommer Bicycle pavement. Without big projects in the pipelines, planning departments have no source of funding and no justification for their existence.

    Without projects, no plans. Without plans, no planning department.

    'Twas ever thus.

  3. So most folks I know saw this flaw as it was being built over the past eons of time. It was predictable. It's tax payers money they burn. They keep their jobs for awhile and move on to the next boondoggle fat and unaccountably.

  4. Auxiliary lanes aren't magic. They can improve traffic flow by providing greater separation between vehicles entering and exiting the freeway from mainline traffic.

    Your anecdotal evidence is unconvincing. This is like the argument, "global warming isn't real because it's cold outside right now". Sucks you got stuck in traffic. That doesn't mean the situation is unchanged since 2011. You gotta back those claims up with some actual evidence, my friend!

    Talk of induced demand is an obvious slippery slope fallacy. I don't think anyone flipped out and gave up carpooling because this one mile of auxiliary lane got finished.

    If traffic has increased, the obvious explanation would be more and more people getting back to work as the economy recovers from the 2008 recession. You know. Rush hour.

  5. It's obvious that PhysicsPolice hasn't read the literature on induced demand. It's not about increased traffic, it's about patterns of behavior of existing motorists, who drive where it's most convenient, thus backing up traffic in the same place when capacity is increased.


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