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And you can't just pay $75 a year and drive as much as you want on the ICC

Minor nitpick: I understand that was a news source that got the 55K number, but I've read through the studies and the actual number is a bit higher. That said, the overall gist of your post is still valid.

Let me correct myself...the numbers I referred to were the projected future traffic...I think that 55K figure is for right after the ICC opens. I'll go slink into the corner now and die...

I'm no ICC supporter, but your analysis would be stronger if you could compare the "value" of a CaBi trip to the "value" of an ICC trip. The number of trips is not a good comparison because I would guess that the value of a trip on the ICC is probably significantly greater than on CaBi. Sure, both systems can be used for economically productive activity but I would guess that the average CaBi trip doesn't generate quite so much economic activity as the average ICC trip.

If not value per trip, then certainly some other metric would be more appropriate than simply the number of trips.

plus distance as a factor.

Nonetheless, I think this is a worthwhile comparison. Thanks.

+ what about the terrible terrible injustice of "condemning" some parking spaces for bike sharing?

This is an overly simplistic analysis, but I'm not sure the "economic activity" differs much, except perhaps in the cases where the ICC is being used by trucks. It also would need to account for multi-passenger vehicles. A better measure would be passengers than trips. For CaBi those are the same things, for the ICC they are not.

I'm not sure mileage matters much. No one says "i'm going to go drive for 6 miles" they say "i'm going to drive to work" or the market or to something. Without the ICC people would choose to live closer to those things or use other modes. Example: In Rockville, you can get to DCA on Metro, even if it is a long haul. But the ICC might move BWI closer than DCA, but now by car. That's not really a win.

Froggie does hit on the point that a better analysis would be the 25 year cost (construction and operation) less the 25 year revenue (fees or tolls). But those numbers are harder to find.

and here's one more:

  • ICC traffic volume is significantly under projections (even for the segment currently in service), whereas
  • CaBi membership and trips are significantly over.

I'd suggest running this again after the ICC is finished up... comparing an incomplete ICC is like comparing a bikeshare system with a low density of stations: you're not quite getting the full picture of what it could be.

...Not to say the ICC will win out in the end; I'm pretty sure the numbers will still end the same :)

I'd say that if they laid a few railroad tracks for MARC (that could be leased by freight lines) instead of the ICC that it would costs less, be better for the environment, and arguably generate more economic activity.

Add a trail and we'd be in business...

Since CABI uses existing roads and lanes, this seems very, very problematical to me. A system that requires new thoroughfares (à la ICC) is generally going to much more expensive than one that doesn't. As cyclists, however, we want new infrastructure, so this kind of calculation may work against our interests.

Bossi, I'm using the completed ICC projected numbers. The number of trips on the completed ICC is 10,000 per day.

guez, it's true that CaBi uses the existing infrastructure, but very little of it. The ICC uses existing infrastructure as well because it connects in to all the other roads. In general the costs of the existing, complimentary infrastructure isn't counted in the costs. For example, we don't count the cost of all the rest of Metro when calculating the cost of the Silver line. Where CaBi causes wear or tear on infrastructure, removes parking spaces, or pushes out other uses on District-owned land (which isn't free, though admittedly is counted as so) those are fair costs to be considered, but I suspect they're trivial.


It's not just a question of wear and tear. The point is that CaBi wouldn't work at all unless the infrastructure was there, and that infrastructure cost money to build in the first place. Don't get me wrong: it's good to take advantage of existing infrastructure, but sometimes new roads need to be built, and that costs money. Some of the costs of future roads need to be built into the "cost" of CaBi. Even if there were no cars, roads would need to be repaired from time to time because of erosions, freezing and thawing, etc.

guez, "The point is that CaBi wouldn't work at all unless the infrastructure was there"

How much infrastructure does it really need. Even if we had dirt roads, CaBi would still work - and possibly better than driving. And isn't the above statement true for the ICC as well. Not to mention pretty much everything. If you built an airport but there were no other airports or airlines it wouldn't be much good. So do we include the cost of all the other airports and all the airplanes and all the airline infrastructure and the entire air traffic control system in the cost of an airport? No.

To a certain extent CaBi is a free-rider on the current road network, but what's really happening is we're monetizing an underused asset. No one counts that as a cost. Not in business. Not in government. No one. But, if you'd like to, I'd be interested in hearing what you think the true cost of CaBi is.

I suspect that the point made in the posting is essentially valid, which is why we're seeing things like CaBi. I can imagine a smart guy like Gabe Klein sitting in a meeting with his staff. They are desperate to add capacity to the transportation system. The throw around ideas about new roads, bridges, tunnels, trains, buses. For every idea, the cost is in the billions and the timetable is in years if not decades. (Except for the Circulator bus, but that's done and you can't do it again.) Then someone talks about walking and biking and the timetable is months and the cost is millions, not billions.

Think about this: imagine having the task of finding a 2% capacity increase in the transportation system. That could mean about 20 new lane-miles of roads for DC and about 10,000 new parking spaces. Or it could mean adding two more Metro stations and a couple miles of track. Or it could mean doubling the number of people cycling. I'll admit that no one knows exactly how to do that, but it's not going to cost billions of dollars. If transportation were my job I'd be throwing down paint for bike lanes too.

"To a certain extent CaBi is a free-rider on the current road network, but what's really happening is we're monetizing an underused asset. No one counts that as a cost. Not in business. Not in government. No one."

Monetizing an underused asset is a good idea. But sometimes building infrastructure is necessary: bridges, separated bike lanes, etc. When a new road is built, there is no reason to arbitrarily decide that it is part of the "cost" of automobile infrastructure but not part of the "cost" of bike infrastructure, as if only roads only existed for cars. Let's say we banned cars in central DC. Surely at that point, necessary repairs to roads, sidewalks, and bridges would need to considered as part of the cost of the bicycling/pedestrian infrastructure.

But if you want to move somewhere without paved roads and set up a bikesharing system, be my guest.

As for what the true cost of CaBi is, I have no idea, but I agree that it is much cheaper per rider-mile than the ICC. I would suggest, however, that at the very least we should consider a share of the cost of bike lanes. This should include not just the cost of barriers and markings, but the cost of maintaining the road surface devoted to cycling.

But this isn't a comparison of the cost of bicycle/pedestrian infrastructure to car infrastructure. I don't understand why CaBi has to carry the cost of the entire bike lane system as a "cost".

I think you're making the mistake of reading into this an argument that we don't need infrastructure. I recognize we need highways and bridges. But the cost of the ICC really is an automobile infrastructure cost, since right now they're the only ones using it.

This is more a response to those who would argue that CaBi is too expensive. Expensive compared to what? I would ask. Compared to the ICC?


I understand and agree with the general point, but you're comparing very different kinds of things: the cost of building road infrastructure and the cost of implementing a system for sharing vehicles (which still have to use road infrastructure). Either you need to take the cost of the road infrastructure into account (by considering not the totality, but rather CaBi's *share* of the bike lane costs) or you're really comparing apples and oranges. It doesn't really mean anything to say that CaBi is cheaper "per ride" than the ICC if you're talking about different kinds of costs. It's cheaper for me to buy a Starbucks in the morning when I drive to work than it is for me to buy a Metro ticket, but the coffee is only a small part of the cost of my drive.

Excellent post.

Left out are the costs of the cars, the roads connecting to the ICC and a little gas and insurance.

guez, We didn't have CaBi. Then we spent $5M. Then we did have CaBi.

We didn't have an ICC. We'll spend $2.5B. Then we will have an ICC.

That's kind of the definition of cost right?

Wash, what you're describing is pretty much a textbook description of marginal utility and marginal cost -- which is the proper way to look at it. Sunk costs don't matter because they're sunk.

Since our transportation system is pretty much built out the marginal cost of adding new capacity is sky-high -- except for cycling and walking.

I agree with the conclusion, but a stronger comparison would be passenger-miles, not just passengers.

Even then, you are giving an unfair advantage to CaBi because you are not taking into account time spent traveling per mile (e.g., 1/2 hour out of a person's day has the opp. cost of $x).

"Wash, what you're describing is pretty much a textbook description of marginal utility and marginal cost -- which is the proper way to look at it. Sunk costs don't matter because they're sunk."

Yes, I agree.

(same anon)

FWIW, I agree with Wash that miles simply don't matter. Since I decided to drive less, I've dropped my total miles (car plus bike) from about 14000 five years ago to less than 7000 last year. The result has been an increase, rather than decrease, in my quality of life. Trips matter, miles don't.

+1 on Jonathan's post.

Since I started bike commuting I also reduced my total miles significantly. All while having more fun...

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