Cars as far as the eye can see, you roll forward 10 feet and stop right on the car’s bumper in front of you. As you approach 15 minutes straight with various degrees of pressure on your brakes, you finally snap – “F@RT!” We have all been there. No one likes traffic, some people just deal with it better than others – for the 58% of Americans that live in large cities, it is a real problem. In my lifetime it seems like not much has been done to fix it – maybe make a new lane here, add a stoplight there, but nothing game changing. Is this all we can do?
Back in high school my friend Tony and I sat in traffic a lot as we had over an hour drive to the other side of LA for our club volleyball practice. He pondered “what if everyone who is sitting in traffic only thought about ways to solve traffic? Would we find a solution?” I’m not sure, but I do know it is a problem worth solving – millions of productive person-hours are wasted in cities across the world by needlessly sitting in cars that aren’t moving.
The hillbillies will say “how about you just move out of the city? If we just make smaller cities we don’t have this problem.” Bad solution – cities lower pollution, raise production, result in higher pay, have more culture, and encourage ambition. So back to the drawing board.
One of the biggest contributors are traffic signals – they make you sit and wait for your turn. How can this be improved? Let me present some of the thinking that has been done over the years. The biggest improvement that can be made is to eliminate left turns. This would allow us to go from a 4 cycle stop light to only 2. San Francisco chooses to annoy people by simply not allowing left turns in some parts of the city – you have to take three rights! I hope we can do better than this.
Over 50 years ago the Jughandle was introduced in New Jersey. On the West Coast this is commonly seen on freeway overpasses – rather than taking a left turn to get on the freeway, you take a right and go around a big banked 270 degree turn, passing under the road you were originally on (or stopping at the traffic light if there is not a bridge). Kind of confusing taking a right instead of a left, takes up a lot of space, but sometimes it is an improvement!
Around the same time in another part of the country the Michigan Left was introduced. Just like the Jersey Jughandle, you go past the intersection to make a left turn. Except this time you make it from the left lane (which is intuitive) and make a U-turn followed by a right turn when you get back to the intersection. I like this approach and Wikipedia indicates that it is starting to gain a little traction in various parts of the world. However, this requires significant space in the median, which is not always available.
Within the last 10 years an engineering student wrote a paper about a new kind of intersection: the Diverging Diamond Interchange. Is this going to finally be the answer? It looks pretty sweet, watch the video below for a simulation:
There are dozens of other possibilities, ranging from the absurd to a simple roundabout, but I’ll spare you the detailed analysis. From learning about all of these it is apparent we should standardize on a couple of approaches, lest we end up needing to watch dozens of videos like this one explaining a “continuous flow intersection”:
In conclusion, there is no one answer to this problem. There are dozens of possibilities, all with their pros and cons. The approach with the least congestion is to add another dimension to the equation – a bridge or tunnel. However this is not cost effective. Alternatively if we had unlimited space around the intersection, there are some very interesting things that can be designed. Or we could just take the UPS approach and optimize our driving by taking as many right turns as possible!
Main source: Don’t Turn Left!
Great ideas and thoughts. One of the main problems with traffic is the sheer number of cars on the road. Here are some other ideas (some traditional some untraditional) to reduce congestion:
1. Plan, build, and incentivize public transit
2. Incentivize off-peak driving (same idea as using off-peak energy)
3. Taxes, tolls, and higher prices for gas and parking
4. Provide incentives/tax breaks for businesses that have a certain % of teleworkers in their workforce
All the videos and ideas are great and should be considered/implemented where appropriate. Most infrastructure engineering problems, in my opinion, are best solved with a portfolio approach that treats both the root cause and the symptoms.
Great post skinner 🙂
You are right. Cars make up traffic and if there are less of them, things would be much better.
Your ideas certainly get at the root cause and try to incentivise cars to get off the road. There are all sorts of good libertarian ideas here that are worthy of a separate post (teaser: http://en.wikipedia.org/wiki/London_congestion_charge). The problem with most incentive schemes are that they make it so poor people are priced out. Is driving a privilege for the rich that can afford a high gas tax (or other incentives) or is it something for everyone since we all pay taxes (and equally enjoy other benefits)? Solution: have less babies, especially if the parents are below average intelligence!
Yes, the tricky thing about all these modern incentive solutions is they so often combine ideologically opposed ideas. But without them, fancy engineering models will only defer the pain. As Kasey said, it requires a multi-faceted approach and even then traffic is tricky.
You should (rationally? pragmatically?!) couple congestion charges with great public transportation options. I don’t know if the economics would work out, but congestion charges in theory would go a long way to subsidizing such a system. However, then you’re taxing the wealthy AND asking them to pay for transport options that are “by rule” their public good as well, but in reality, are used more by the less fortunate than the luxury car owners you see flying through London, e.g.
Another problem is, of course, that all these solutions require a reasonably effective and strong local government, probably backed by federal funding. Systemic solutions require command-control governing more than the typical laissez-faire American approach. “You’re gonna tell me where I can and can’t drive my car? And you’re gonna charge me more for it? TAXED ENOUGH ALREADY!” Our current political system doesn’t seem to be able to muster the clout to institute sweeping anything changes. There is infrastructure degradation at every level of the US transport system. Maybe there are positive case studies out there?
The solution? I don’t know. I think denser cities with public transportation and a whole lot of smart one-way traffic flows are clearly a good model. New York is the obvious example. You can build these cities relatively easily from scratch — However, what to do about the so many suburban places like LA, where there are really, truly no feasible solutions without non-economic, politically unfeasible infrastructure transformation on a massive scale? I guess you have incremental solutions and sputter along unhappily. Certainly seems to be the way it’s going.
Ah, traffic… another symptom of systemic modern-society-issues that we should all hope are not intractable.
You are right that a congestion tax to pay for public transportation, really just is taxing the rich and giving to the poor. Historical precedent shows a certain amount of this is acceptable. But you can spin it a little differently – the benefit to the wealthy is that there are less cars on the road because of the tax, so they can get around much faster.
The practicality of all this in the United States is another matter entirely. Can’t we just dream in our bubble Utopian society?
Check this out — slightly off discussion but very topical for the post. Uber (the black car market-making iPhone app in SF) has a blog. They wrote about parking… apparently SF is the first city to count its parking spots, and is moving towards measuring spot popularity and thus being able to charge metering rates to match demand. This will likely result in 1) more revenue for the city and 2) more incentive to use public transportation! pretty cool.
http://blog.uber.com/2010/12/14/why-owning-a-car-in-sf-doesnt-make-sense/
Dude. I LOVE THAT DATA. I hate SF parking. I get sooooo many tickets. I have still not bought a residential parking permit after living in the city for two years because they are only open the exact hours that normal people work. Unfortunately I work 40 miles from their building, so I can’t make there conveniently. Nonetheless, I went by a couple weeks ago when I was working from home. They require your registration say a SF address (check) and a second form of ID. But that second form of ID can’t be your drivers license. In fact, it has to be a utility bill, bank statement, or copy of the lease. Not only that, it has to be a physical, printed out version of one of those – so the bills that I get emailed bc this is the 21st century can’t be shown to them on my iPhone. SO DUMB!