Category: Safety

Where does this road diet rule come from?

April 17, 2013 / / 7 Comments

55th Street road diet from summer 2012. This is the best road diet photo I’ve got. Traffic counts here indicate 15,700 cars daily (based on a single day of measurement in 2006).

“Roadways with Average Daily Traffic (ADT) of 20,000 or less may be good candidates for a road diet and should be evaluated for feasibility”, via FHWA. The documents – here’s the second one – I’ve found so far on FHWA’s website don’t explain the research behind this assumption. How should a road be evaluated for feasibility? The second one bases review of a street on crash type, severity, and rate.

View 4600 W Foster Avenue in a larger map. Alderman Laurino is correct in her description of how many lanes are here. The road is only striped for 1 lane in each direction.

This concerns me because CDOT seems to have adopted this as a policy. They are using it as a reason to not consider a road diet on Foster Avenue. However, though, Foster Avenue between Pulaski Road and the Edens Expressway has only “1 and a half lanes” in each direction, according to local Alderman Marge Laurino of the 39th Ward (see John Greenfield’s interview below, which is an expanded version of one published on Grid Chicago in two parts).

Interview

Greenfield: Where in your ward would you like to see speed cameras installed?

Laurino: Well right now I don’t know that we have locations that would fit some of the criteria that we’re looking at. Currently I think the ones that they’re putting in are going to be where there have been pedestrian fatalities and I don’t know that I have anything that fits that really strict criteria but I would… Just a suggestion, Foster Avenue in front of Gompers Park. I mean it’s often times an area where cars really speed because for whatever reason, where there are no homes and that and it’s just wide-open parkland people just seem to hit the accelerator. I don’t know why that it but it appears to be the case.

JG: Is that a long stretch with no stoplights?

ML: From Pulaski to Cicero it’s a long stretch and it’s not one lane. I want to call it one-and-a-half lanes. There really shouldn’t be two lanes of traffic going in one direction but they seem to squeeze that in. So anyway that might be a potential place for a camera. We’re also looking at something called a road diet, where we just, through paint markings and paint striping, make the street narrower. That would be on Foster Avenue, let’s say between central Park and Cicero.

JG: Is there any talk of putting in bike lanes there to take up the extra space?

ML: No, for whatever reason it doesn’t fit their criteria.

Survivor bias: Who walks away from automobile crashes?

February 14, 2013 / / 3 Comments

This photo of a damaged car has little to do with this post. 

Then my friend Alex E. asked, “Is there a reason why?”

I can’t leave such a question hanging. I thought I read that somewhere, and it was probably in Tom Vanderbilt’s book, Traffic. What I found in there mostly referred to trucks (the semi-trailer type) because of their mass and how people not driving trucks behave around them on the road. The second part explained the statistics around who lives and dies in crashes involving a drunk driver.

Knowing that, and knowing the story I tweeted a link to, you’ll see that the event didn’t involve a truck and my relating them was perhaps unsuitable. It did involve drunk driving, but I may have misread the book text.

Here’s what Traffic says about trucks

“When trucks and cars collide, nearly nine of ten times it’s the truck driver who walks away alive.” Vanderbilt discusses how that is (page 247).

…we all likely have proof of the dangerous nature of trucks. We have seen cars crumpled on the roadside. We’ve heard news stories of truck drivers, wired on stimulants, forced to drive the deregulated trucking industry’s increasingly long shifts. We can easily recall being tailgated or cut off by some crazy trucker.

Just one thing complicates this image of trucks as the biggest hazard on the road today: In most cases, when cars and trucks collide, the car bears the greater share of what are called “contributory factors”.

Really? Car drivers caused crashes with trucks and then die from it?

Instead of relying on drivers’ accounts, he [Daniel Blower at Michigan Transport Research Institute] looked at “unmistakable” physical evidence. “In certain crash types like head-ons, the vehicle that crosses the center much more likely contributed to the crash than the vehicle that didn’t cross the center line”.

After examining more than five thousand fatal truck-car crashes, Blower found that in 70 percent of cases, the driver of the car had the sole contributing responsibility in the crash.

Basically, the car drivers in a car-truck crash caused the crash and ended up being the ones dying.

…the reason trucks are dangerous seems to have more to do with the action sof car drivers combined with the physcial characteristics of trucks and less to do with the actions of truck drivers. “The caricature that we have that the highways are thronged with fatigued, drug-addled truck drivers is, I think, just wrong”, Blower said.

“In a light vehicle, you are correct to be afraid of them, but its not because the drivers are disproportionately aggressive or bad drivers”, Blower said. “It’s because of physics, truck design, the different performance characteristics. You can make a mistake around a Geo Metro and live to tell about it. You make that same mistake around a truck and you could easily be dead.”

What Traffic says about drunk driving

Of the 11,000 drunk-driving fatalities studied by economists Steven D. Levitt and Jack Porter, 72% were the crash-causing drunk driver or their passengers, and 28% were the other drivers (most of whom were not drunk themselves) (page 251).

Current madness of the week: investigating car crashes

February 10, 2013 / / 2 Comments

Gravity should have prevented this car crash, as would not placing buildings near roadways. But we’ve figured out how to defy gravity. Photo by Katherine Hodges.

“Police closed the street to investigate”.

What a waste of time. The investigation will conclude the same way as any other, with one or more of the following contributing factors: exceeding the speed limit, alcohol, a deficiency in someone’s driving skills or knowledge, or some defect in the road (I’m excluding poor road design as it could almost always be better, designed in such a way to reduce the occurrence of poor quality driving).

The story: a person driving an SUV side swipes another SUV. The driver loses control and then hits the center concrete barrier. The SUV flips over and the driver dies. (Yes, this is in relation to an incident on I-294 in Glenview this weekend.)

We already know how to fix all of these issues.

New Honda commercial tells people it’s okay to drive their car while sleepy

October 31, 2012 / / 4 Comments

Eff you, Honda.

Partial transcript:

We know you.

[Shows guy yawning.]

We know you have to rise early and work late.

[Shows someone drinking coffee. Shows “Lane Departure Warning” signal and an obscured person driving on a rural road driving their Honda Accord in the opposite direction lane, then swerving back into the correct lane.]

With not enough sleep in between.

[Shows hands of driver moving the steering wheel to maneuver the car back into the correct lane with driver’s shoulders moving dramatically to either show that the steering wheel had to be yanked or that he’s shrugging off the moment.]

The rest of the commercial shows different features and makes stupid comments about your needs and desires.

It’s not okay to drive in that condition.

Is there a member of the ITE who will stand up against bad road designs?

October 1, 2012 / / 9 Comments

Sharing the road is one place to start. Why should one on a two-wheeled, muscle-powered device pedal along side a garbage truck with blind spots? Wait, why does an automobile even have blind spots? This enormous right-turn lane is one example of “dangerous by design”. 

Update October 5, 2012: For a great example on why I cannot – and why you should not – support bad road designs is this story of a fatal bike crash on a major biking “commuterway” in Chicago. We must stop building narrow bike lanes to the left of parked cars and we can be done with this type of crash for good.

The infrastructure as we have it in Chicago and many other American cities cannot support any increases in bicycling. The operation and design of our infrastructure creates a finite limit for the number of people who will bicycle on it. I’m not talking about how many people can use it, but how many people want to use it.

We’ve seen infinitesimal growth in the bicycle’s mode share for commuting to work, so small that the growth might not actually be growth at all because all the reported increases are within the range of error (the Census Bureau being the collector and distributor of the data). Our infrastructure is not safe, and that is what inhibits an increase in bicycling riders and trips that the City of Chicago, its mayor, its council, its officially adopted plans, and its people, desire. Until our roads are made safe, the cycle growth will remain minuscule or non-existent. The only other significant factor in promoting cycling is high gasoline prices, but even as they remain high, the cycle growth (or spike, seen in 2008) hasn’t returned.

It’s a small group of people who are designing and maintaining our roads. And they are the first group of people we listen to when we say we want safe roads. Instead of the people who’ve actually built safe roads.

The ITE is the Institute of Transportation Engineers, and, like many organizations, has a code of ethics. In their Canons of Ethics document (.pdf), there are at least two sections that require members to stand against bad road designs.

Section 1: The member will have due regard for the safety, health and welfare of the public in the performance of professional duties.

Section 11: The member will guard against conditions that are dangerous or threatening to life, limb, or property on work for which the member is responsible, or, if not responsible, will promptly call such conditions to the attention of those who are responsible.

A study in Portland, Oregon, found that 60% of residents wanted to bike, but had concerns about safety.

These residents are curious about bicycling. They are hearing messages from a wide variety of sources about how easy it is to ride a bicycle in Portland, about how bicycling is booming in the city, about “bicycle culture” in Portland, about Portland being a “bicycle-friendly” city, and about the need for people to lead more active lives. They like riding a bicycle, remembering back to their youths, or to the ride they took last summer on the Springwater, or in the BridgePedal, or at Sun River, and they would like to ride more. But, they are afraid to ride. They don’t like the cars speeding down their streets. They get nervous thinking about what would happen to them on a bicycle when a driver runs a red light, or guns their cars around them, or passes too closely and too fast.

American roads are dangerous by design. It’s time to fire the people who design them that way.

Year after year, roads in Chicago are ripped up, repaved, and restriped in exactly the same way that existed before. Miles of missed opportunities for safer roads. This essay says nothing of the lack of police enforcement of traffic rules, for which there is little empirical evidence. The essay may be updated from time to time, but I won’t be noting each change.

An example of a better design: the buses and bikes don’t mix, and automobiles turning left cannot be passed by through-automobiles. Bicyclists are safer.