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OK I'll play...

The CEI comment was predicated on losing traffic lanes, and thereby increasing congestion. Although I am not sure, the 15th street cycleway removed parking, and therefore is not subject to the comment.

The comment seems to define congestion as reduced speed and is therefore equivalent to traffic calming. Whether this is good or not, depends on what one views as the appropriate speed. The conclusion is almost tautological. Traffic calming just sounds nicer than congestion.

In fact, the cited studies show that the average speed on the road decreased. After all, speeding was reduced dramatically. In order for average speed to remain constant, slower drivers would have had to speed up with the bike lanes.

This is corroborated by the data. The median speed on 15th Street fell from 28 to 22 mph. The sampling technique used by the NYC DOT is unlikely to measure true average speed as it is unlikely that a DOT employee would flagrantly speed (regardless whether the speed limits were appropriate :) )as the average civilian might do.

I agree that the emissions effect is unclear and the emergency response comment inappropriate if the bike lane is not physically separated from traffic lanes.

Headline: "Man Employed To Be Wrong by Organization Funded to Manufacture 'Wrongness' Wrong."


The strange thing is you see the "emissions" argument everywhere, and from what I can tell, it's utter horseshit. There's no evidence whatsoever that reduced traffic throughput causes an appreciable increase in emissions--other than an appeal to "common sense."

And, yeah, the "OMG PPLE ARE DIIEING!!1" argument is just embarrassing. Although, I would not that someone capable of embarrassment would not be working for the CEI in the first place.

Mark, the 15th Street cycleway also removed a lane of traffic.

The comment seems to define congestion as reduced speed But that isn't what congestion is. If the speed limit on a country road with 5 cars an hour is reduced, speed would go down, but that wouldn't be traffic congestion.

Mark, I guess it depends on how NYC DOT measured the travel time. Did they drive a car on the route and then measure that, or did they watch cars as they entered the study area and as they left and measure that time. Because the latter would adjust for the problem.

It is entirely possible for the average speed to go down and the average travel time to remain constant if there is less dwell time. Gunning it to a red light and sitting for 30 seconds and travelling at a slower speed to catch the light just as it turns green has drivers going at different speeds but similar travel times.

I always thought that congestion was gunk in the system that slows things down. Our difference in definitions is that you require that gunk to be cars. Further, I note the commenter uses the weasel word "often" to modify the occurrence of congestion, which could mean anything.

(I doubt that posting a lower speed limit, without the addition of cops would change actual speed on a lightly used rural road.)

As to NYC DOT methodology, I would think they actually drove to get travel times (or maybe used records from city vehicles with appropriately-programmed GPS units). The times are sufficiently long and distances far enough suggesting that the only alternative way to measure transit time would be to use synchronized video cameras at both ends and matched cars entering and exiting the study area. This also takes into account vehicles that turn out of the study area.

As to the mathematics of average speed, this depends on whether one is measuring speed over the entire study area, which includes the dwell times, or at a particular point. While it is certainly possible that bike lanes lower the incidence of speeding at particular points, but does not reduce overall average speed over longer distance, this begs the question of why bike lanes stop the seemingly irrational behavior of drivers speeding just so they can get stopped by the next red light.

On the emissions argument, I imagine the reason that you don't see evidence on the effects of congestion is that it is very difficult or costly to measure. One can measure a emission/speed curve (or fuel consumption curve) for a particular car, but it would be expensive to conduct fuel consumption/congestion curves for a fleet of cars under controlled scenarios. Furthermore, I don't believe the technology is available to directly measure emission levels in areas of congestion versus elsewhere.

I require the gunk to be other vehicles. I don't count, for example, roadside trees that psychologically encourage drivers to slow down. Or, in this case, a narrower road, which also encourages drivers to slow down.

If you follow the links, it turns out they did actually drive to get the travel times. Which still only means that the road is harder to speed on.

I think the speeds are measured in certain locations, but the travel times are done over the entire length (and that's what I mean by average speed).

I think bike lanes - or in this case narrower roads - stop the seemingly irrational behavior of drivers speeding just so they can get stopped by the next red light because they now have fewer options to speed. They need one of three lanes to be clear of rational people instead of 1 of 4.

I agree that emissions are hard to measure for the reasons you cited, which is why Scribner should not have claimed that narrower roads cause more emissions.

Bikes, parking, and urbanism in general seem to be particular blind spots for the right.

I would think that the irrationality would stop the irrationality, but, then again, I rarely drive in this city: That would be crazy.

Ooooooh the Koch Brothers! Scary!

On item #3 it seems Marc Scribner is perhaps a believer in design by fire truck. OK I have a solution! Dedicated emergency vehicle lanes. Right next to the dedicated bike lanes, of course.

Oh, but that would create more congestion and toxic pollution that helps bring on more heart attacks and thus the need for more dedicated emergency vehicle lanes.

Less cars on the road answers all his concerns. Just as free parking exacts a high price (as Marc admits is true), then so does undervalued roads. When cars pay full price admission there will be less on the road. That is my economic perspective!

I know Marc Scribner. I an know he's a cyclist. All cyclists stink.

Wow. That is some expert analysis, William.

Dear my Blog Friend,

Ha! I am a commuting cyclist. I don't own a car. But I appreciate "Henri's" comment, even though I suspect you have never read anything on transportation or traffic engineering in your life. How else could you explain: reducing road capacity in Manhattan improves (or has no effect on) LOS because Magical Fairy Cyclists can float above congestion?! Because Midtown isn't already on the left tail of the emissions U?! Because removing auto lanes doesn't have an equal or greater effect to EMS response as installing speed humps?! As someone who loves to bike, I suggest you read a bit more.As you're a self-styled Internet "cycling advocate," it's practically you're duty. Or something.

Love, Kisses, and all the Rest,

Ignore the punctuation and spelling errors above. The spirit is there, just not the editing.

If this is the real Marc,

How else could you explain: reducing road capacity in Manhattan improves (or has no effect on) LOS because Magical Fairy Cyclists can float above congestion?!

Gosh Marc, I don't know. Perhaps I looked at the actual data NYC DOT produced which showed that the average speed dropped from above the speed limit to slightly below it. Which means the road was over capacity. Imagine you had a 100 lane roadway with 1 user per day. And then you removed 99 lanes. Would LOS go down? No. That's the oversimplified explanation of a road diet, which is what this is.

And I'll add that LOS is terrible metric anyway.

Because Midtown isn't already on the left tail of the emissions U?!

If it is, prove it.

But your own study showed the platau to be between 25mph and 50 mph. The NYC DOT data shows that average speed is above 25mph. So no, it doesn't appear to be to the left on this road.

Because removing auto lanes doesn't have an equal or greater effect to EMS response as installing speed humps?!

Again, if it does, prove it. You make it seem so obvious, which means the data must be out there.

But again, I'll rebut. Removing lanes does not have the same effect, because most of us move out of the way when there's an ambulance. Speed humps don't tend to do that. Traffic is only congested a few hours a day - but speed humps work 24 hours a day. Most heart attacks occur before the morning rush - so congestion isn't really that big an issue. If congestion is a big threat to health, I have a solution to that, it involves fewer cars, since cars cause congestion.

And even if speed humps have an equal or greater effect, the lameness of the report you cited doesn't really prove that speed humps have a large effect - does it?

As someone who loves to bike, I suggest you read a bit more. As you're a professional Transportational Policy Analyst, it's practically your duty. Or something. And if you do read more, try some Philosophy texts - since that was your concentration. I'd specifically recommend some on ethics and intellectual honesty.

Let's face it, you're a professional analyst. You know more than me about this stuff, yet in about an hour I was able to totally discredit your points. And do you know why? Because the "studies" you cited are total bullshit - and you know it - that's why you don't mention the uncomfortable details. You know the positions you've taken are total bullshit as they're built entirely on rhetoric and are backed up only by bullshit studies. You know the positions you've advocated are false and that you haven't done the due diligence to back them up. You know that you willfully omitted facts that are relevant because they work against your position. What do you call that? I call that lying. I call that unethical. And what does that make you?

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