So This Is Why They Are So Cranky…

Written by Boston Biker on Sep 21

I got the chance to be a passenger in a car a couple of days ago. Just riding around town, getting stuck in traffic. Not epic traffic, just normal Boston traffic. We were not in any kind of hurry, and the company was good so we were upbeat and enjoying the ride. However I have to say, wow…driving is slow. I am sure other smarter people have thought about this before, but here is what I noticed.

Because cars take up so much space, you can get a road pretty packed full with only 30-40 of them. Which is in most cases 30-40 people (people drive alone). Because cars have to accelerate and decelerate pretty slowly in stop and go traffic (they don’t have the room to really gun it without smashing into the car ahead of them), and because they take up so much space, interesting things happen at red lights.

If the road were empty except for one car, that car would stop at each red light only once (by which I mean it would only sit at that intersection through one red light cycle). We can call that an X1 red light. Put more cars on the road and eventually you reach a “critical mass”, so that a car at the end of the line has to wait at the same red light more than once (one green gets most of the people through, then the cars at the back wait for the next green to go). Add more cars and you end up waiting at a single red light 3…4… or more times. We can call them X2 lights, X3 lights, etc. Get enough cars on a street with a 5 or 6 physical red lights and is like that road has 10-20 virtual red lights on it because each person stops at each red light multiple times.

In essence traffic breeds more traffic. The more cars you have trying to fit through the same “pipe” the longer it takes for those cars to go through. You could solve this problem several ways. You could figure out how many cars it takes to reach the “critical mass” number for each street and not allow more than that number of cars on the street, London tried something like this with it’s “congestion charge”. You could put those 30 people on a bus, in essence putting everyone into one “car” then they would only have to stop at each red light once. You could also put them on a train, in essence removing all the cars from the road and making the red lights irrelevant.

I doubt that Boston is ready to implement a congestion charge, and because the city has no readily defined “core” it would be impracticable. The bus and train options are good, especially for morning and afternoon commute scenarios. You have a lot of people all going to the same place at the same time. Makes no sense to all be in separate vehicles. And as we see above, everyone suffers when everyone drives.

However what about when you are not commuting, what about Saturday, or middle of the day, or running errands. Erratic traffic, where you don’t want to go where the bus is going, or you have to go where the T stop isn’t? I would say that the best possible transportation option is then a bicycle. On a bicycle you are legally allowed to filter down the right hand side to the red light (you still have to stop at the red light). By filtering to the front you are removing the X red problem that cars have. You stop at each red light only once, it is as if you are a lone car on the road. Turning each X2 or X3 red into an X1 red. Because of this you will almost always go faster than each individual car (average speed and actual speed).

Ironically (as cars often think it is bikers slowing them down), you will also be helping the motorists go faster. Each person on a bike instead of in a car reduces the “critical mass” number by one. Remove enough cars and the X3 red light becomes an X2, remove even more cars and each car will be able to fully clear through at each red light. The remaining cars then experience the speed of having less cars on the road. The cyclist reaps the benefits of faster travel, cleaner air, less motorists (and thus less danger from them), a fatter wallet (bikes are cheap compared to cars/t-pass) a greener planet, and nicer calves. A classic Win/Win.

Tags: benefits of cycling, cranky, motorists, red lights
Posted in advocacy, education | 5 Comments »