1nterceptor

“Our findings show that bike lanes or paved shoulders by themselves do not significantly reduce the severity of injuries sustained by cyclists,” says co-author Dietrich Jehle, MD, professor of emergency medicine in the UB School of Medicine and Biomedical Sciences and at Erie County Medical Center. “The data show that other factors may be more important in reducing the severity of cyclists’ injuries, including the speed of motor vehicles traveling near them and how much light there is.”

Read the full article:
https://www.king5.com/news/Study-Bike...209988921.html

UberGeek

I don't think they reduce the severity, per se. However, they've shown to reduce the numbers of them, when properly designed.

Bekologist

And, bike lanes are frequently installed in conjunction with a road diet or other traffic calming measures that reduce vehicle speeds, reducing severity in the event of a collision.

350htrr

Duh. No shiet, getting bumped by a car going 50MPH on a bike lane I would "suspect" would be the same result as where there isn't a bike lane.... JMO

CommuteCommando

+1

This seems pretty intuitive.

buzzman

Does this seem like a report that was just looking for a reason why "bike lanes don't work"? I mean in some ways it makes about as much sense as saying, " Bicyclists must pedal just as hard to go 20 mph whether they are in a bike lane or not." the conclusion being " no advantage to a bike lane shown by this study."


The article does state:

But does so in such a way is to imply that this research disputes that.

Very poorly written article. Interesting read in that it is so odd.

John C. Ratliff

Anyone have a link to the actual study? Everyone here is reacting to news stories about the study, and not the study itself. This is not a primary source document, but is secondary or possibly even third-hand. I would like to see the actual study, and what the specifics are. I have tried a Google search, and only get news stories about the study.

Having noted this, please read this statement from the news article:
In the safety profession, we have an ANSI Standard known as Z10-2005, American National Standard for Occupational Health and Safety Management Systems. In that there is a tool called the Risk Assessment Matrix. I have modified it slightly with a numerical system (I have worked in professional safety for 35 years or so):
https://i3.photobucket.com/albums/y76...mentMatrix.jpg
If you look at it, frequency is as important as severity. You can see that even if the severity is catastrophic or critical, if the likelihood of occurrence is remote (not likely to occur) or improbable (very unlikely, may assume exposure will not happen), the risk assessment matrix is much different than if it were frequent (likely to occur repeatedly) or probable (likely to occur several times).

Here is a quote from another study from Johns Hopkins Center for a Livable Future at the Bloomberg School of Public Health on bike lanes, which does have a link to the actual study:

John

FBinNY 

The survey results shouldn't surprise anybody.

The most sever accidents tend to happen at intersections. While there are instances of cyclists hit by passing cars, these are a smaller percentage of the total and tend not to be as sever as many of the intersection crashes.

Bike lanes which still have those same intersections therefore don't address the major cause of the most severe accidents, and so won't have a major impact on the total accident rate. Moreover, because most side-of-the-road lanes create confusing and conflicting flow patterns at intersections they can (and do) increase the accident rate there.

Imagine a 4 lane (2 in each direction) road as it approaches an intersection. It might have arrows in the right lane showing right and straight, and in the left lane straight ahead only (no left). Now imagine the same road, with the left land marked straight or right. Suddenly we have a problem with right turners from the left lane, crossing the path of straight ahead drivers to their right.

There's no way a road would ever have those markings, and traffic flow, yet that's exactly how the flow is with most along the road bike lanes.

buzzman

I'm not sure if the OP article was conclusive regarding the accident rate. It seemed to only reference accident severity, which other posters have pointed out are two very different things. Your post seems to imply an increase in the overall accident rate in bike lanes due to an increase in accidents at intersections.

My understanding was that while come from behind accidents were less likely than accidents at intersections the severity of come from behind collisions was greater.

#1 Could you reference the study you are drawing these inferences from? I'd love to look at it.

# 2 Are you saying that bike lanes have a negligible impact on the accident rate in general and increase the rate of accidents at intersections? Or are you saying that bike lanes reduce accidents except at intersections?

Chris516

Why am I not surprised by this.

This is one reason why I won't ride in bike lanes.

FBinNY 

My conclusions aren't based on a single study, but based on reading the available literature spanning 40 years. In many cases there are conflicts, probably based on how and where data is collected, and how it's interpreted.

I'm sorry if I implied that bike lanes cause an overall increase in accidents, that wasn't intended. But, as the study referenced showed, they don't cause a decrease in the severity of accidents. I was pointing out that that was logical in that lanes don't address the issue of intersections.

As to whether hit from behind accidents on shared lanes cause more sever injuries than intersection accidents, that probably depends on where you're collecting data. On the open road, where car speed is high, and where drivers may be more likely to not expect bicycles hit from behind accidents tend to be at high speed, and the injuries severe. But in urban areas, drivers expect bicycles, and the speeds are lower, and the danger shifts from being hit while passed, to being hit at intersections.

My problem with bike infrastructure is that it's an expensive approach, and often doesn't address the problems effectively. I'm not opposed to some changes in the infrastructure, especially to painted bike lanes, which at the very least serve as reminders that cyclists will be on the road. IMO, a more cost effective solution is to focus on driver education, and changing driving habits of both cyclists and motorists. Unfortunately with the explosions of cell phones, texting, and the amount of non-automotive technology being fitted into cars today, we're headed in the wrong direction. (at least until collision avoidance systems become mainstream).

John C. Ratliff

FBinNY, please re-read post #7, as I have edited it with more information.

John

Bekologist

you mean, the findings that you're less likely to get hit while riding in a bikelane?

Bekologist

BUT that's not a logical inference...bicycle networks that use bikelanes DO address the issue of intersections.

Bike lanes DON'T increase conflict at intersections, they are designed to, and have the strong potential to, mitigate conflict.

emphasized crossover zones, dashed or cessation of the bikelane stripe, guide striped thru intersections, turn restrictions, increasing awareness of bike traffic, all these are frequently associated with intersection bikelane design, and mitigate conflicts, not exacerbate them. Either the Oregon or the California models, both intersection treatments are designed to, and do, mitigate conflict.

chipcom 

Contrary to what you may see in your own fishbowl, Bek, in most parts of the country, "bike networks" are pretty much just painted lines on the shoulders. When (if) the day comes when well designed bike networks...or just bike lanes...become the norm, I'll probably be long dead.

ephin

I've been commuting 7 years now - approx 4K commuting miles per year. I've seen an increase in the number of bike lanes (esp in philadelphia) over these years. In my experience, they are no safer than roads without bike lanes. In fact, in my experience, they might be more dangerous. While I haven't been tracking the statistics, I swear pedestrians and car doors are more likely to unexpectedly enter a bike lane than when there's no bike lane. I've had numerous encounters. It's as if they assume it's a safe buffer zone from traffic and it never occurs to them there might actually be a bike in the bike lane!

lostarchitect 

...Why would anyone expect that a bike lane would reduce the severity of accidents?

chipcom 

some think that paint has magical powers

genec

Because when you are hit in the "traveled way" the severity is less? Interesting physics magic there.

UberGeek

I'm not sure why. A cyclist impacting a car generally is just as severe, bike lanes or not.

I do think there's support showing it reduces the frequency, but not the severity.

lostarchitect 

Yeah, to me this seems like a red herring type study.

buzzman

Yep. And it seems that some are only too willing to take the bait. The article, and the study, seem pointless to me. No new or valuable information here.

Bekologist

King 5 brought this to light, probably because they don't like the bikelane plans for in front of their studio, i think its a separated, floating parking bike lane. Here's a screen shot of the bike lane in front of King 5 right now, the city has plans to beef up the bike facility on Dexter i believe....

https://maps.google.com/maps?f=q&sour...12,261.62,,0,0

dynodonn 

Looks like a typical DZBL, fine and dandy when running alongside a row of compact cars, but in my locale, the family car tends to be newer full sized pickup trucks with extended towing mirrors, or with flat beds, some with over sized tires, with both vehicle and mirrors extending well out into the BL at times. Fun and games when contending with fast two way traffic on one side, and dodging truckzillas on the other, and taking the lane for any period of time other than a few seconds is not recommended when following motorists see a "perfectly good" BL off to the side.

Bekologist

yeah, yeah, no bike lane wide enough for you....... you think this buffered bikelane along Dexter presents heightened dangers for cyclists from car mirrors, sure sure.... whatever you say....




so, what do you recommend for Dexter in front of King 5? In front of King 5 the road is close to 100 feet wide.... it's 4 lanes, parking and bikelane, parking strip and sidewalk both sides now.

road diet with an even wider buffered bikelane, or cycletrack?

The city isn't going to give this road, one of the major N/S routes into downtown Seattle, back to motorists and force cyclists to 'take the lane' in front of the vehicle traffic.

modern NA cycletrack is in the city's next bike master plan, which is why KING 5 is promoting this view on bike lanes perhaps?