A Thought Experiment


In past (work) lives I traveled across the USA and worked in many different cities. I think by the time I was done I had worked in 30+ states at one time or another. When I worked in Minneapolis, for instance, I was struck by the fact that when traffic was clear, most cars would travel near the speed limit, or maybe 5 or so mph faster. This pattern repeated itself in most other cities where I was forced to get a rental car and drive to the client on a regular basis.

In Chicago, on the other hand, on the few times when traffic is not congested, the average speed on an interstate highway like the Kennedy or Dan Ryan or Eisenhower is WAY up in the 80’s. Even in a construction zone (like today on I88), if you drive near the posted speed limit, you are like a rock in the stream.

One of the clearest ways to test this proposition is to leave the Chicago loop on one of the few times it is not congested (say, Sunday morning) and take I290 (Eisenhower) West, towards the suburbs. I290 “starts” from the loop so when you get on it is WIDE open… and then as the exits move on traffic gets worse until you reach gridlock (on most days, not on a Sunday).

This photo shows the wide open traffic from the view of my high powered almost a decade-old Nissan Altima. You can see that I am in the middle lane.

The EXPERIMENT would be – how f*cking fast would you have to go in order to stay in the left lane until it ends (at Austin, when I290 inexplicably loses a lane) and NOT get passed, assuming it was mostly wide open in front of you. On a typical day you’d have to go at least 100 miles / hour because people are absolutely FLYING down that road. It is even crazier on the Dan Ryan once you get south of the Loop.  I know that I am not crazy enough to do it.

I don’t know what it is about Chicago drivers but they seem possessed to drive as fast as they can in the brief moments that they can see daylight and clear pavement.

Cross posted at LITGM

17 thoughts on “A Thought Experiment”

  1. I think on topic (that is, I think your point would be given your previous post): A friend buys cars from an Iranian mechanical engineer; his family’s pretty observant and he goes back often, but he says he would never want to live in Iran again. His reason: no one stops at stop signs; in Houston, even at night and with no one around, people stop. (He may exaggerate some, but at least they slow down.) It’s how much people have internalized both values & customs that makes for a civil society. (Or, as I put it, I don’t want to live anywhere where I have to lock my doors.)

  2. I think part of the problem may be the posted speed limit of 55-there’s no possible way people are only driving 55 when it’s possible to drive faster than that. And once you’re driving something reasonable, like 70, you’re already 15 over, so what’s 10 more mph over. I think something as simple as raising the speed limit to 70 would really help. If you want, think of that as a kind of “broken windows” theory of speeding.

  3. The reason I obey the speed limits in Ohio is that there are cops running speed traps at all hours of the day and night. I wish they would devote their efforts toward apprehending criminals, bu that would be hard dangerous work.

  4. how f*cking fast would you have to go in order to stay in the left lane until it ends (at Austin, when I290 inexplicably loses a lane) and NOT get passed, assuming it was mostly wide open in front of you.

    Probably the speed of light. The speed at which a lot of people drive is determined by the speed that others around them are driving at. This creates a feedback loop in which those who drive the fastest causes others to driver faster which causes the fastest drivers to drive even faster.

    On a related note, I remember reading a study back in the 90’s which showed that you could predict the economic success of a country by measuring the rate at which people voluntarily obeyed traffic laws. The more people ignored the laws, the worse the economy. Apparently, obeying traffic laws is a form of cooperation and provide a cultural measure for overall cooperation.

  5. “It is even crazier on the Dan Ryan”

    Many years ago I saw a vehicle cut across 6 lanes of heavy, fast moving traffic to make the exit. I still can’t believe he (or she) made it.

  6. I do that drive fairly often. I used to do it all the time.

    I find that the left lane on the Eisenhower when it is not rush hour is going about 75 mph. It is not a particularly dangerous speed.

    For some reason, there do not seem to be a lot of cops on the Eisenhower.

  7. I agree on not too many cops on I290. And the average speed is probably something like 75mph.

    But the question is… how fast would you need to drive over there not to get passed – which would mean that you were going to take on any one else who wanted to drive faster – most times when I drive it there is someone (at least 1-2) that are just flying by on that left lane or changing quickly to pass. You’d have to be willing to stay ahead of the nuts…

  8. I suspect that the maximum speed at which many people will drive depends in large part on the speed of the guy in front of them. Several drivers in a group, all going fast, are like fish in a school: one of them might get stopped by the cops but it’s unlikely that all of them will; the larger the group, the better the odds for each driver individually. So one guy who drives extremely fast could raise the speeds of many other drivers who would drive slower if that fast driver weren’t around.

  9. The locals set the tone. They know where the speedtraps, curves, and exits are. The autobahn-like PA Turnpike NE extension is regularly +25 [over the speed limit] and so is the twisty Meritt Parkway in CT. The difference is that 90 MPH on the turnpike isn’t a maximum but 80 MPH on the Meritt is.

    A columnist suggested that if we want to reduce carbon output we eliminate the speed limit on superhighways like the PA turnpike (for non-trucks). If you could do 120 MPH between Philly and Pittsburgh then flying would make less sense. The only dangerous thing about doing 120 MPH on the PA turnpike is the other cars – trust me :)

  10. And the fog, rain, and snow. And the trucks passing each other for a 2 mph advantage. Wait for the third lane.

  11. Here in Virginia drivers mistake the I-95 sign as the speed limit.

    The fastest I have gone in the states has been on I-25 between Colorado Springs and Denver. The flow of left hand lane traffic approached Autobahn speeds.

  12. “How fast would you need to drive over there not to get passed?”

    I have worked late, and been driving home at midnight on I290, very clear of traffic, cruising at about 80 in the left lane, and had people pass me, coming up and getting closer then jinking into the center lane to go around me, going substantially faster. They were going over 90 for sure.

  13. The fastest I have ever driven for an extended period, including on the stretches of I-10 and I-20 in west Texas where the posted speed limit is 80 mph, was some years back (before the repeal of the national 55 mph limit!) in the left lane of the Tri-State Tollway in Lake County. A steady 85 mph, well into Wisconsin.

    Does anyone here have experience driving in Montana during their experiment with no daytime speed limits?

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