I had a few more insights and expanded my critique of this research. I posted the paper on my website at:

http://bicyclingmatters.wordpress.com/critiques/parking-and-bicyclists/

Regards,
Wayne

Critique of Slides:
Slides 11 and 12 seem to be purposefully inflammatory and divisive through the use of the word “confrontation” to describe what should accurately be called an “interaction,” establishing a pattern. In their previous study, “Evaluation of On-Street Bicycle Facilities Added to Existing Roadways,” the CTR repeatedly mis-used the word “swerve” to describe motorists simply moving left to pass a bicyclist. The message of these mis-characterizations appears to be that bicycling and motoring are inherently incompatible, and bicycling is disruptive to motoring, which supports the segregationist approach of bike lanes the CTR espouses.

Slide 15 shows nearly identical behaviors in a bike lane on Georgian and in an outside lane with parking on Alamo, demonstrating that such space need not be designated as a discriminatory bike lane. To improve poor bicyclist behavior, Parking Crosses with long extensions can be placed to warn of the door zone, similar to those shown in Slides 6-8.

Slide 16 and 19 are in error. The Wide Outside Lane on Guadalupe is not really wide because the door zone should not be considered part of lane width. This is analogous to a lane being narrowed with construction barrels. The CTR investigators recognize that operating in the door zone is contraindicated, so should be able to rationalize that the door zone is not to be considered part of usable lane width. Slide 19 shows Meadow Glen as 13.5 feet, which is narrower than AASHTO’s (and TXDOT’s) 14 foot minimum, which itself is demonstrably too narrow even on a road without parking. In their previous research, the CTR similarly examined “wide” lanes that were substandard width. In this study, only Cincinnati is a true Wide Outside Lane.

Slide 17 is in error because it says “Same Total Width” when this is obviously not true: Parkfield North is 17.5 feet while San Jacinto is 20.5 feet.

Critique of Study Conclusions:
“2) Operationally, marked bicycle lanes are superior to wide outside lanes (without marking).”

Comments: Slide 14 shows that on Parkfield North with a bike lane motorists’ ENC was 41%, whereas on Cincinnati (just 1 foot wider) motorist ENC was 0%. By the investigators’ definition, Cincinnati with a wide outside lane was operationally superior for motorists. And while bicyclists operated slightly further left on the Parkfield North bike lane, there is no reason all bicyclists on both roads could have ridden outside the door zone while motorists easily passed in the remainder of the lane. Competent bicyclists always avoid the door zone. Parking crosses with long extensions on Cincinnati would deter unknowledgeable bicyclists from operating in the door zone.

Again, there is only 1 true wide outside lane used in this study: Cincinnati (Slide 14). The other alleged wide lanes are technically narrow lanes because the door zone narrowed them.

“3) Total roadway width is critical to safety and operations for both cyclists and motorists.”

Comments: There is no evidence that actual safety is a function of roadway width. That bicyclists may ride in the door zone is a function of bicyclist competence; competent bicyclists avoid the door zone no matter road width. A motorist straddle passing of his own volition due to the presence of a bicycle driver is not a safety violation unless it has been demonstrated as a contributor to collisions. (Encroachment is misused by the investigators. It’s correct use occurs in situations when a motorist crosses a line due to a mistake.)

“4) Where parking is allowed, a bicycle lane with a buffer space is the only way to ensure that cyclists are removed from the door zone of parked vehicles.”

Comments: The “only way?” This is demonstrably untrue. The research found that some bicyclists avoided the door zone no matter the road layout. Parking Crosses (shown in slides 6-8) without a left bike lane stripe can ensure that, as can competent bicyclists who are knowledgeable of the dangers of door zones.

Critique Conclusions:
This research demonstrated that the paid population of mostly unknowledgeable bicyclists ofttimes operated in the door zone. This occurred on both government placed bike lanes that invite and mandate this poor behavior, as well as on normal roads on which the bicyclist ought to be competent enough to avoid the door zone. The research findings would have been quite different had the CTR paid only knowledgeable bicyclists rather than modeling the behavior of those who are ignorant of a significant hazard.

The investigators wrongly concluded that a bike lane with buffer is the “only way” for bicycle drivers to avoid the door zone. Clearly, some bicyclists in their study avoided the door zone on all the different roadway configurations.

The authors should have concluded that competent bicyclists avoid the door zone. The data on the Cincinnati Wide Outside Lane are illustrative: there is a large spike of incompetent bicyclists operating in the door zone and a smaller spike of apparently competent bicyclists outside the door zone at 5 feet. Even on roads where the government-placed bike lanes compelled bicyclists to the hazardous door zone, some bicyclists had the knowledge and fortitude (motorist harassment for bicycling outside a bike lane in the then created “motor vehicle lane” can be substantial) to disobey the bike lane stripe and operate outside the door zone.

d’amico… how does the graphical representation, which i too found easy to follow – even ingenious – highlight the problems with bike lanes?

As I understand it, the most recent proposal from the city is to only make one side no parking. It’s hard to keep track of what the current plan is — http://www.lobv.org/ has what I know of to be the latest news.

Still, parking on one side is better than parking on both sides, but it doesn’t qualify as `no parking in bike lanes’.

Thanks for covering this! Glad to hear it went well, and that the petition is starting to have an affect.

http://www.dahmus.org/iofiles/trans/bl-wcl-pd.html

http://bicyclingmatters.wordpress.com/critiques/bicycle-facilities-added/

It’s worse than junk science and does not bode well for this new report.

Wayne