Wednesday, May 27, 2009

the direction of the deflection

The bike path ends... and cyclists are forced into traffic... and exterminated!

We like most speed bumps on a bike. They can be fun.

They are known as vertical deflections in traffic design lingo. Speed bumps are a type of "traffic calming" which causes cars to slow down (but then they speed up faster to compensate for their time loss).

The interesting thing is the direction of the deflection, speed bumps cause you to go up. On a bike it's easy to manage and not unsafe.

Which brings us to the other direction of deflection. Yes, we’re talking about horizontal deflections.
These are extensions from the curb that extend out into the roadway in order to narrow the street. They are all over Montreal.

The theory is that car drivers perceive a narrower road, so they don't race down at autoroute speeds.
Most horizontal deflections are benign. But there is one where the Cote-Ste-Catherine bike path ends at Villeneuve, and a horizontal deflection thrusts all continuing-east bike traffic on C-St-C road into the car traffic lane.

Now the question is, is this on purpose?

We have been reading the very interesting book "Traffic: Why We Drive the Way We Do (and What It Says About Us)" by Tom Vanderbilt. In it he looks at traffic, the rules and regulations and looks at how traffic design and engineering try to manage road use and safety, and then compares this to what it is like in the real world. Do traffic safety designs work in the real world?

One insight is that cars go faster when the driver perceives "the coast is clear." SO, the more obstacles that the driver sees, and the more things he sees in HIS lane of traffic, then the driver becomes more cautious (ok, maybe not exactly cautious, but maybe slightly less omnipotent), and the driver slows down.

Slowing down is good. Car accidents can kill. But they kill a lot better when the car is going over 50 km/h. So slowing car speeds on city streets to below 50 km/h is really of critical importance.
Anyone who knows Cote-Ste-Catherine road knows that lots of cars are traveling at speeds above 50 km/h.

So my theory is that this horizontal deflection is designed to make the traffic more complicated, which will make the car driver feel less safe and therefore make them slow down. The result will be a safer street.

Like I said, that's a theory. But frankly, as a cyclist, this thing scares the hell out of me.
Back to the theory: so that means I am scared and I look more carefully around me, and over my shoulder at the cars coming up behind me, and look for gaps in the traffic flow and be more careful!

back to reality...

We suppose that the other reason that this horizontal deflection exists is to make cyclists turn east onto Villeneuve street to join other Plateau paths going south to downtown.

At this point the typical cyclist brain, which is highly tuned to finding the shortest and most direct route to travel, starts ringing the alarm: Detour! Detour!

To us it looks like this path actually ends a few hundred metres before it should.

The reality now is that that many cyclists will continue to travel straight down Cote Ste-Catherine towards Mont Royal Avenue. And these cyclists will all be thrust into the car-traffic lane (aieee!) with this new horizontal deflection. We hope everyone survives this little horizontal ski-jump into the speeding traffic of Cote-Ste-Catherine road.

We believe that this bike path should continue all the way to Mont Royal avenue. That is the logical end to the Cote-Ste-Catherine road bike path. We find Villeneuve to be a very narrow street between Parc and Cote-Ste-Catherine. It barely fits two cars. And there's a hill.

We are happy that we are not the traffic design engineer trying to solve these problems. It's a tough job!

The horizontal deflection at Coco-Rico would be perfect for a much-needed bike parking stand.


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