Thursday, December 9, 2010

Increasing rudeness on the trail

As I've posted before, one reason I love bike commuting is to escape the rat-race mentality. The ability to go where you want, at the speed you want, without being hampered by heavy traffic, leads to a calmer ethos on the bike trail than you find in a car at rush-hour. But perhaps bike commuters are beginning to pay the price of their own success. As more of us take to our bikes, tensions inevitably will rise.

I had two experiences within a week of each other that lead me to believe we are beginning to see a transition. In the first, I was approaching 15th Avenue NE in the U District from the east. There's no traffic light there, but there is a stop sign, so I always do a "biker's stop" before crossing, meaning that I slow down enough that I could stop cold if I had to, and then assess the situation as I approach the street. In this case there was another biker in front of me who came to a complete stop, so I moved left to pass, checked the traffic, and saw that the only approaching vehicle was a shuttle bus coming from the south. Since I could easily cross before it got near I accelerated across the street and settled back into my ride.

A block or so later the biker who had stopped caught up with me and started yelling. From her perspective it appeared that I had simply powered through the stop sign, making me one of the bad guys giving bicyclists a bad name. I defended my actions (in the heat of the moment I claimed to have actually stopped, whereas the truth was that I had merely slowed down), but of course there was no agreement. It ate at me for awhile, and then I put it aside as an unfortunate misunderstanding.

A few days later I was approaching 65th from the north, slowed to a crawl, and then proceeded when the lone approaching vehicle slowed and was apparently waiting for me. As I crossed I waved, as I always do, but when I got across the street I heard a string of invective from the driver. Evidently I had misunderstood his intentions. This incident disturbed me even more than the prior one, because it made me wonder whether in fact I was as much in the "good guys" camp as I had thought. Could it be I was actually one of the aggressive bicyclists that everyone hates?

These two incidents have made me change my behavior. Although I had considered myself one of the more conservative riders on the trail, I have become even more conservative. But after much reflection I have come to the conclusion that I really am, and always have been, one of the "good guys." The fact that I'm encountering more conflict recently is, I believe, due to the increasing tension that increasing numbers of bicyclists causes. Drivers have had more negative experiences with bikes, and are therefore quicker to lose their cool. Other bikers, stung by bikers' increasingly bad rep, are quicker to judge their fellow commuters. It all leads to greater tension, and the beginnings of the rat-race mentality I so much want to escape.

I think we've reached an inflection point. Seattle has recently been named one of the most bike-friendly cities in the nation, but we're still nowhere near where some European cities are. We're moving in the right direction, and we have recently crossed a threshold where car drivers encounter bikes with such regularity that it's no longer just the odd circumstance when a road is shared by both cars and bikes, it's the norm. But we don't yet have a good enough network of trails and bike-only lanes to bring some order to the process.

As a hopeless optimist, I see all this as generally a good thing. More bikes is better, and though the inevitable conflict it engenders is unpleasant, the future is bright. Let's see if we can all keep this perspective. And if you happen to see agressive behavior by a biker with a big black trunk sporting an "I brake for lemonade" bumper sticker, give him the benefit of the doubt. He's doing the best he can.

Thursday, May 20, 2010

How safe is bike-commuting?

There are 1.25 fatalities for every 100,000,000 miles driven in a car. That doesn't seem like much, but if you travel 20,000 miles per year for 50 years it works out to a better than 1% chance that you will die in a car crash.

The statistics for bicycling are less complete, but such as they are they suggest that the rate per mile is about ten times as high compared to driving. To keep calculations simple let's just call it 10 fatalities per 100,000,000 miles.

Call me chicken, but this is alarming. Applying the statistics directly to my own situation, I ride upwards of 5,000 miles per year, giving me odds of 1:20,000 of dying this year while biking. Over a 20-year career that's a one-in-a-thousand chance of getting killed. Compare this to other risky activities:

  • Skydiving (per jump): 1:100,000
  • Killed by lightning (lifetime): 1:100,000
  • Plane crash (per trip): 1:1,000,000

The EPA, when assessing the risk of pollution levels, typically sets one in a million as unacceptably high. I'm comfortable with a one-in-a million risk; one in a thousand, not so much.

So how can I go about mitigating this risk? Quite a lot, I believe. What I see on the road convinces me that there is a lot of opportunity for bicyclists to improve their own chance for survival. To be honest, I'm astonished at the foolhardiness of many bikers. Here is just a small sample of behavior I've seen:

  • Crossing a busy intersection without checking whether car traffic is aware of you. I actually saw someone get hit crossing 65th this way, and I've seen several close calls on Stone Way. How hard is it to look left and right?
  • This one's similar: going straight through an intersection without looking for oncoming left-turners, or right-turners coming up behind you. At least one recent fatality in Seattle was caused by this situation. It's not much comfort to claim that the car was at fault.
  • Riding on unsuitable roads, such as Aurora Avenue North (which also happened to be the location of the above-mentioned fatality).
  • Riding at night in dark clothing with no lights. As a car driver with aging eyesight, I can assure you this renders you practically invisible.

I maintain that simply by taking common-sense precautions, the risk of accident can be dropped substantially. Statistics back this up. For example, one blogger has assembled data showing that young, inexperienced cyclists incur accidents at greater than ten times the rate of experienced cyclists.

But even experienced cyclists take risks that I myself avoid, so I believe in my case the risk is lower still. I know I've annoyed many a bicyclist with my cautious riding on the Burke-Gilman trail. Because of poor visibility I slow nearly to a stop at 70th and 65th to make sure no one's coming; I won't cross in front of a car until I make eye contact with the driver and have been given a clear signal to cross, particularly at high-traffic crossings like Blakely.

Recently I've been looking for the best route between Fremont and the Interbay Golf Course on Magnolia. My first attempt took me over an unacceptably steep hill. On my second attempt I tried a route that crossed the Ballard bridge, taking me within a few blocks of my destination, only to find that the pedestrian walkway on the other side didn't continue along 15th NW. My only options were to follow the safe route away from my destination, or to ride on the street. One look at the street convinced me to bail. I ended up taking a 15-minute detour just to avoid the traffic. Finally on my third try I found a suitable route that was pleasant, direct, and safe.

I have the added advantage that nearly 90% of my commute trip is along the Burke-Gilman trail, away from auto traffic entirely except for the street crossings. Cautious riding, experience, and a favorable route combine to reduce my personal risk to perhaps as low as 1:100,000 lifetime, I estimate.

That's still not one in a million, but it's almost certainly lower than the risk I would incur driving to work instead. Yet one more reason to ride!

Saturday, February 27, 2010

How much does it REALLY rain in Seattle?

For twelve months now (March 2009 through February 2010) I've been keeping track of weather conditions for my bike commute. I have been telling everyone for years that I really don't get rained on that often, even in the winter - and now I have the stats to prove it.

First some basic definitions. I decided to code every commute on the following scale:

DRY - Totally dry commute
MISTY - Encountered some mist or very light rain, but not enough to get wet.
LIGHT RAIN - Encountered light to moderate rain, enough to have to hang up my bike clothes to dry, but not a soaking rain.
HEAVY RAIN - Got as wet as you can get - had to wring out my socks after arrival.
UNRIDEABLE - Weather looked so icky I wimped out and took alternate transportation
N/A - Didn't bike, but for reasons unrelated to the weather.

There were a total of 261 work days last year for a total of 522 potential commutes. 192 of those fell into the "N/A" category, meaning I was either on vacation, worked from home, or commuted some other way for reasons unrelated to the weather.

Here's a chart showing my commuting statistics by month:

The first thing that should be obvious is that most of the chart is green - 76% of my commutes were completely dry, and another 9% had only a little misty rain. Even in the rainiest months over half of my commutes were dry. How can that be, when Seattle gets rain 138 days/year? The answer is that on rainy days it usually doesn't rain ALL day. Often I get lucky and stay dry even on days that get a lot of rain.

Here's another chart that illustrates what I mean:

The column on the left shows commuting statistics on days that had measurable rainfall. 67% of those commutes were DRY or MISTY, meaning I only got wet one-third of the time. On days that had no measurable rainfall, of course, nearly every commute was dry. The one day that I wimped out was because of cold, not precipitation. (We had that stretch of weather in the teens in December).

This still doesn't tell the whole story. Suppose I look outside my window in the morning and see that it isn't raining, and furthermore I check the radar and can see that it won't rain for at least another hour, so I'm guaranteed a dry morning commute. What is the probability that my evening commute will also be dry?

According to my year's worth of statistics, the answer is 91%. There were 139 morning commutes coded as DRY or MISTY; 126 of them were followed by evening commutes coded as DRY or MISTY. On only 13 occasions was a dry morning commute followed by a rainy evening commute.

Is Seattle cloudy a lot? Yes. Does a light, misty rain fall frequently? Also yes. But the statistics prove that you won't get very wet very often. So get out there and ride!