Custis Trail Riders – Take the VDOT I-66 Survey

[DismalScientist]

@WillStewart 9819 wrote:

Yes, citations are indeed important, as they help others understand how one came to take a particular position on a subject;

Generated and induced traffic;

1. Todd Litman, Generated Traffic and Induced Travel – Implications for Transport Planning, 8 June 2011, Victoria Transport Policy Institute

2. Patrick DeCorla-Souza, AICP, ACCOUNTING FOR INDUCED TRAVEL IN EVALUATION OF URBAN HIGHWAY EXPANSION, Federal Highway Administration
[/INDENT]

Thank you.
I do not argue that induced traffic does not exist. The argument that you made is that the “log jam” effect would decrease throughput in the long run because of lowering the cost of driving. This is equivalent to saying in Litman’s argument that the initial price decline along the short run demand is more than compensated by the outward shift in demand and in the long run, the price of driving would increase on net, ceteris paribus (all else equal). This is equivalent to an upward sloping long run demand curve. As a dismal scientist, I am compelled to state by the relevant licensing authority that upward-sloping long run demand curves do not exist. Hence, I said you statement was logically inconsistent.

The DeCorla-Souza article correctly categorizes sources of induced travel. My argument is that point 6 is important and I value automotive traffic being induced from unimproved facilities (Washington Blvd) more than I devalue traffic moved to the improved facility (I-66).
(Furthermore, if I lived closer to Arlington Blvd, I would make an even stronger argument that the restrictions on I-66 caused the joy and pleasure that the pseudo-freeway that Arlington Blvd has become.)

[DismalScientist]

@WillStewart 9821 wrote:

What tends to happen over and over again (Til Hazel, Toll Brothers, etc) is that land speculators influence the elections in outer suburbs and exurbia to install development-friendly politicians. These politicians then change land use plans (or grant waivers) so that developers can turn farmland into housing developments. The houses are inexpensive, because the land is inexpensive, and the taxes are initially cheap. When roads, schools, etc have to be built, then taxes go up and residents blame the politicians who come later.

Gee…. It seems mighty short-sighted of the voters out there to allow such politicians to be installed against the voters’ self interests.

[baiskeli]

@DismalScientist 9820 wrote:

True enough. Without increasing density, it is difficult to develop transit systems. The problem is that many people do not want to live in dense areas.

I’m not so sure about that.

Some people don’t, sure. But we don’t need all of them to for all of us to benefit. Certainly we have no trouble fillling the apartments and condos in the dense areas of Arlington, and elsewhere.

Do people want to limit geographic growth and bear the costs of increasing density; do people want to limit population growth in an area, thereby reducing economic opportunity and local asset values and forcing population growth issues to other areas; or do people want let things go on as they are and bear the increased congestion and infrastructure costs? I don’t think there is a political consensus in this area and I think proponent of various positions tend to discount these inherent tradeoffs.

I think you’re offering another false dilemma. We don’t have to force limits on growth or population. That’s why the term “smart growth” was coined. We can offer the choice of high density or not, with the choice of transportation modes that go with that, and let people choose what they want. Right now, we put far too many resources into the low-density, car-dependent side. Enough people will choose high-density, and this will benefit those who want to drive around too by getting them off the roads and easing development pressure in the hinterlands. And when it comes to public policy, that means not constantly throwing money at widening or building new highways all the time, for one thing.

We are building a huge Metro line along the I-66 corridor right now. That’s a good choice, and we’ve already made it.

[baiskeli]

@DismalScientist 9823 wrote:

Gee…. It seems mighty short-sighted of the voters out there to allow such politicians to be installed against the voters’ self interests.

Oh, boy, now you hit on another issue dear to me, but one with which I agree with you completely! But I’m not wading into this one.

[WillStewart]

@DismalScientist 9822 wrote:

Thank you.
The argument that you made is that the “log jam” effect would decrease throughput in the long run because of lowering the cost of driving.

Actually, that is not what I said. The cost of driving can be measured in several ways, including financial, time, stress, etc. My contention is that generated/induced traffic would create a logjam in the system (especially at the Rosslyn tunnel and Tysons ‘feeder’ road, if not also at the Roosevelt Bridge), reducing the person/hour rate of throughput. Part of this is related to culture, as well. A person in this area may be willing to accept a higher cost of driving if they are able to drive in by themselves (as the majority does, so the evidence is prima facia). Driving in alone invariably raising the financial and stress costs, and in many (or perhaps most) situations raise the time cost.

@DismalScientist 9822 wrote:

The DeCorla-Souza article correctly categorizes sources of induced travel. My argument is that point 6 is important and I value automotive traffic being induced from unimproved facilities (Washington Blvd) more than I devalue traffic moved to the improved facility (I-66).

This is a multi-variate problem, though, so my contention is that point 5 (and others) will overwhelm point 6.

[DismalScientist]

@baiskeli 9824 wrote:

We don’t have to force limits on growth or population. That’s why the term “smart growth” was coined. We can offer the choice of high density or not, with the choice of transportation modes that go with that, and let people choose what they want. Right now, we put far too many resources into the low-density, car-dependent side. Enough people will choose high-density, and this will benefit those who want to drive around too by getting them off the roads and easing development pressure in the hinterlands. And when it comes to public policy, that means not constantly throwing money at widening or building new highways all the time, for one thing.

We are building a huge Metro line along the I-66 corridor right now. That’s a good choice, and we’ve already made it.

“Smart growth” as you have defined it is a hybrid solution: increasing density in some places and letting development spill out in others. I imagine opponents of Smart Growth would characterize it just increasing density. Given that people have difference in their desires to trade-off congestion vs. density, I would imagine the likely outcome would be such a hybrid result.

We shall see if the Silver line is a mistake or not. I don’t know what the ridership will look like, but with the tolls on the DTR increasing imposing a tax on drivers, it will be interesting to see the reaction. (I’m glad I don’t live off route 7!)

[DismalScientist]

@WillStewart 9826 wrote:

The cost of driving can be measured in several ways, including financial, time, stress, etc. My contention is that generated/induced traffic would create a logjam in the system (especially at the Rosslyn tunnel and Tysons ‘feeder’ road, if not also at the Roosevelt Bridge), reducing the person/hour rate of throughput. Part of this is related to culture, as well. A person in this area may be willing to accept a higher cost of driving if they are able to drive in by themselves (as the majority does, so the evidence is prima facia). Driving in alone invariably raising the financial and stress costs, and in many (or perhaps most) situations raise the time cost.

This is a multi-variate problem, though, so my contention is that point 5 (and others) will overwhelm point 6.

1) I took your statement to mean in the long run quantity (throughput) falls. This implies to me that the total (private) price increased, whether expressed in monetary, time, stress, etc. terms.
The fact that people drive by themselves tells me that they view the costs of doing so (whether monetary or other intangible) is lower than their other alternatives, be they carpooling, bicycling, transit, whatever. I view the choice of transportation as an optimization problem, not one of “acceptance.” Just because people drive doesn’t mean they want to, only that it is the least costly solution for them.

2) It most certainly is a multivariate problem. It is hard to model. As invisiblehand points out, there are few natural experiments and how do you properly account for all else equal. There are massive endogeneity problems with trying to measure the effect of induced driving on the quantity of throughput demand? Where’s the data? 😮

[WillStewart]

@DismalScientist 9829 wrote:

The fact that people drive by themselves tells me that they view the costs of doing so (whether monetary or other intangible) is lower than their other alternatives, be they carpooling, bicycling, transit, whatever. I view the choice of transportation as an optimization problem, not one of “acceptance.” Just because people drive doesn’t mean they want to, only that it is the least costly solution for them.

There are cultural and habit ‘inertial’ factors at play here, however. For example, I introduced a good friend of mine moving back to the area to commuter bus service. He had never taken a bus to work in his life, although there were opportunites in the past. He viewed riding buses as something the lower classes did, not someone like him in the middle class. He’s now sold on the lower financial cost and lower stress (and undoubtedly lower time).

People are also creatures of habit. Even with gas prices over $3/gallon, people continue to drive to work by themselves, sometimes for long distances and in SUVs/minivans. One interview I remember is of a person commuting from Loudoun to Arlington in an SUV who answered the question about what he was going to do about the tripling in gas prices with, “What can you do? You just have to suck it up and pay the pump prices.” We come from a very different mindset, so putting ourselves in the shoes of others is not as easy as it would seem.

@DismalScientist 9829 wrote:

2) It most certainly is a multivariate problem. It is hard to model. As invisiblehand points out, there are few natural experiments and how do you properly account for all else equal. There are massive endogeneity problems with trying to measure the effect of induced driving on the quantity of throughput demand? Where’s the data? 😮

My two links above address this from a parameter and algorithmic basis, so additional cites help with empircal (and derived) data;

3. An Analysis of the Relationship Between Highway Expansion and Congestion in Metropolitan Areas, November 1998, Surface Transportation Policy Project

4. INDUCED DEMAND AND ELASTICITY, US DoT, 2002

---

EDIT: By the way, thank you for the collegial tone during our debate. All too often these days, exchanges are exercises in denigrating the other person instead of careful explanation of the facts and their perceived meaning.

[WillStewart]

@DismalScientist 9823 wrote:

Gee…. It seems mighty short-sighted of the voters out there to allow such politicians to be installed against the voters’ self interests.

Welcome to the destructive effect of the influence of money in politics. If you are chagrined by this as well, you may want to attend this event this Saturday.

[dasgeh]

I’ve been watching little kids on Halloween parade. If that doesn’t make you smile, nothing will. But I missed a punch of points I’d like to respond to…

@baiskeli 9806 wrote:

Thanks for providing a countervailing view on this interesting issue by the way – a bunch of people agreeing on everything would be boring as heck.

Completely agree. I think this is a great conversation.

@DismalScientist 9737 wrote:

Growth in the area causes more traffic.

Actually, more cars on the road causes more traffic. You can get more cars on the road by many means. My argument is that building more road will put more cars on the road, and if that increase in the number of cars is greater than the capacity (in terms of # of cars) of the new road you build, then you end up with worse traffic.

More importantly for the discussion of I66, removing the HOV restrictions would almost certainly add cars to the road — right now you have people who agree to carpool only so that they can use I66. If 1 out of every 3 cars on 66 every morning is only carpooling because of the restrictions, then removing restrictions means 1/3 more cars on the road. If you add 1/3 more cars on I66 in the morning, I believe you’ll exhaust capacity, making it slow. If I-66 is slow, drivers will still drive on Washington Blvd to get around it. So you have the same number of cars through Westover, and more cars in Rosslyn and DC. Is that what you want?

@DismalScientist 9737 wrote:

Freeways do not cause increasing traffic on parallel roads unless there is commercial and residential development along those roads and the freeways allow access to those roads.

You conclusion isn’t true in every circumstance. When the freeway is clogged (because of accident, construction, over capacity), it will increase traffic on parallel roads. If more people drive than the freeway can handle, then it gets clogged.

I think there are two main questions to consider:
1. Should we lift HOV restrictions on I66?
2. Should we widen I66?

1. I think the answer here is no, because it means a net increase in # of cars.
2. I say definitely not, not only because I think it will mean a net increase in # of cars in the long run (among other problematic growth patterns). Most importantly, it would cost money (even within the walls). Given limited budgets, any money spent to widen a road is money not spent on bike paths, Metro improvements, driver education, etc etc etc.

On a completely different note, does anyone out there know if there have been studies done comparing the public subsidy of roads (construction and maintenance) to the cost of fixed infrastructure for public transport. I’d be interested to know whether user fees for Metro cover the same types of things that drivers pay for (i.e. the trains, and their maintenance and operation), while the public subsidy covers that same types of things that the public subsidy of roads pays of (building and maintenance of tracks, stations, etc). Just curious.

[baiskeli]

@DismalScientist 9828 wrote:

“Smart growth” as you have defined it is a hybrid solution: increasing density in some places and letting development spill out in others.

No, I think it means when you increase density in one place, you don’t have to have as much development spill out, because the demand has gone down. For instance, some people who would have to live in Loudoun County can now live in Arlington if they want to.

I imagine opponents of Smart Growth would characterize it just increasing density.

You mean increasing density and STOPPING all other development? No, few would say that.

We shall see if the Silver line is a mistake or not. I don’t know what the ridership will look like, but with the tolls on the DTR increasing imposing a tax on drivers, it will be interesting to see the reaction. (I’m glad I don’t live off route 7!)

I hope it works.

[baiskeli]

@WillStewart 9833 wrote:

Welcome to the destructive effect of the influence of money in politics. If you are chagrined by this as well, you may want to attend this event this Saturday.

I don’t think you understood his point.

Here’s how the voters can stop installing politicians who work against their interests: stop installing politicians who work against their interests!

Oh well, here I am dragged into this too.

[DismalScientist]

@WillStewart 9832 wrote:

There are cultural and habit ‘inertial’ factors at play here, however. For example, I introduced a good friend of mine moving back to the area to commuter bus service. He had never taken a bus to work in his life, although there were opportunites in the past. He viewed riding buses as something the lower classes did, not someone like him in the middle class. He’s now sold on the lower financial cost and lower stress (and undoubtedly lower time).

People are also creatures of habit. Even with gas prices over $3/gallon, people continue to drive to work by themselves, sometimes for long distances and in SUVs/minivans. One interview I remember is of a person commuting from Loudoun to Arlington in an SUV who answered the question about what he was going to do about the tripling in gas prices with, “What can you do? You just have to suck it up and pay the pump prices.” We come from a very different mindset, so putting ourselves in the shoes of others is not as easy as it would seem.

My two links above address this from a parameter and algorithmic basis, so additional cites help with empircal (and derived) data;

3. An Analysis of the Relationship Between Highway Expansion and Congestion in Metropolitan Areas, November 1998, Surface Transportation Policy Project

4. INDUCED DEMAND AND ELASTICITY, US DoT, 2002

---

EDIT: By the way, thank you for the collegial tone during our debate. All too often these days, exchanges are exercises in denigrating the other person instead of careful explanation of the facts and their perceived meaning.

As a general point, I really don’t have a dog in this fight. I realize that I have a minority opinion in Arlington on this issue and nothing I do is going to change that. The end result will be determined by the interplay between the state government and Arlington. Furthermore, I am not, in general, a proponent of expanding the highway system and driving in general. As stated above, I view the I-66 thing as an exception where I think the externalities associated with an expansion within the walls are are minor compared to the externalities of traffic on other routes through Arlington.

On the point of people being creatures of habit, I don’t know what to make with such arguments. Although true, any remedy comes across as “I know what right for you better than you do.” I would not want to be on the opposite end of such an argument on any different subject.

On the STPP paper, there is a potential selection issue and a causality issue.

The selection issue involves whether all of the metro areas are similarly situated in terms of the initial level of congestion. If there are a large number of low lane growth metro areas that are not congested at the beginning of the sample and, because of that lack of congestion, they do not build many lanes. If at the end of the sample, they are still not congested, what does that tell us? Well, nothing. However, it does bias down the average increase in congestion for low growth metro areas, affecting the paper’s conclusion.

The causality issue is more important. Are roads built because population grows or because of congestion? The model does not address this. One way to approach this is to make the explanatory variable (i.e. which variable to view has high vs. low construction) as the percentage increase in per capita lane miles. As an extreme example, the population of Las Vegas increased 139%, yet its lane miles increased 50%. Clearly road miles did not increase commensurate with population, yet the study treats Las Vegas as a metro area with high highway growth.

The other study talks about the generic methodology involved in computing a long run elasticity from short run elasticities and other factors. I only scanned it, but it does not seem to present any real estimate responsive to this discussion.

[DismalScientist]

@baiskeli 9835 wrote:

No, I think it means when you increase density in one place, you don’t have to have as much development spill out, because the demand has gone down. For instance, some people who would have to live in Loudoun County can now live in Arlington if they want to.

Sorry, I was less than concise. I don’t know anyone who has to live in Loudoun. I would imagine people choose to live there given their relative valuation of commuting costs, relative amenities (lawn, lack of people riding carbon bikes in full kit when they can be riding a classic steel bike with shifters on the downtube as God intended, (OOPS, that came out?) etc), housing costs, job locations, etc. I don’t see how smart growth lowers housing prices in Arlington so that people in Loudoun would choose differently. If you mean that these people would choose to live in the high density areas afforded by smart growth, then there is a profit opportunity for high density development in Arlington and it doesn’t need to be encouraged by government.

[baiskeli]

@DismalScientist 9843 wrote:

Sorry, I was less than concise. I don’t know anyone who has to live in Loudoun. I would imagine people choose to live there given their relative valuation of commuting costs, relative amenities (lawn, lack of people riding carbon bikes in full kit when they can be riding a classic steel bike with shifters on the downtube as God intended, (OOPS, that came out?) etc), housing costs, job locations, etc.

Sure, and I’m saying that for some, the suburbs come out ahead because the alternatives are so rare. There isn’t much higher-density development to choose, and what is there is expensive for that reason. They may make the best choice for them given the choices, but the choices are limited.

I don’t see how smart growth lowers housing prices in Arlington so that people in Loudoun would choose differently.

You don’t see how someone living in an Apartment or condo in Arlington, perhaps not even owning or rarely using a car, could live cheaper than a standard home in Arlington?

If you mean that these people would choose to live in the high density areas afforded by smart growth, then there is a profit opportunity for high density development in Arlington and it doesn’t need to be encouraged by government.

Ah, but that goes right back to the point – development is inextricably linked to transportation. The government needs to provide the mode of transportation that makes high density development work. And of course there’s other things like zoning involved, to name just one of many factors. There is no pure free market involved here.

By the way, I’ve never debated a real economist and it’s scaring the hell out of me!

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