California's DOT Admits That More Roads Mean More Traffic

http://www.citylab.com/commute/2015/11/californias-dot-admits-that-more-roads-mean-more-traffic/415245/?utm_source=SFFB

by sampo • 11 years ago

66 108 11 years ago

crystaln• 11 years ago

The idea that induced demand entirely compensates for new road capacity is ridiculous on its face. This would only be nearly the case if the road infrastructure is vastly behind what's needed. Even then, much of the newly accommodated traffic will be of economic benefit.

Consider that the theory states that traffic is unchanged because people will be incentivized to drive more because of less traffic. This is self contradictory - there can't be both less traffic and the same traffic.

pfortuny• 11 years ago

Inertia makes things react late to forces. Same here. The article clearly states that the new capacity is essentially filled in the long (10 year range) term, not the short one.

skellington• 11 years ago

Wow, what an illuminating study. If you build roads and the population continues to grow and/or pent up demand is release, those roads will eventually/immediately clog up.

Obviously people use roads until the equilibrium of pain is met (like any economic decision). But, there is a point where you can supply so much capacity that there won't be traffic. It's a lie to say that no amount of capacity can overwhelm all forms of demand.

The only real question is how much road would it take to fully satisfy demand and what would that cost vs the alternatives. (Ignoring pollution issues)

revelation2• 11 years ago

Nobody is saying that. The problem with induced demand for roads is induced demand for personal cars. Transport is a zero-sum game, someone who takes the personal car to work is someone not taking the train. As countless studies attest, this is not of economic (or personal) benefit. It locks people into a life-long dependency on cars with the terrible health outcomes for them personally and the humongous cost of human life in traffic deaths every year.

dsfyu404ed2• 11 years ago

"the terrible health outcomes for them personally"

Cite this, I dare you.

edit: the part I'm not buying is the combination of "terrible" and "personal"

It matters little whether you're sitting on your but for 45min in a car or on a bus, you're still not getting exercise. That's not really "terrible" as it's something that can easily be counteracted unlike (for example) working in a loud environment for 45min twice per day without hearing protection.

The "terrible" stuff (accidents) isn't really personal because it only comes into play on a statistical level (seeing as most people will never be seriously injured in a vehicle accident)

mikeash6• 11 years ago

Transport is not a zero-sum game. People optionally telecommute. People work odd hours (or don't work at all) and take optional trips at peak times. People move closer to or farther away from the places they routinely go (e.g. work).

dsfyu404ed2• 11 years ago

For high demand times of day the infrastructure is vastly behind what's needed...

maxerickson2• 11 years ago

Especially if you take "needed" to mean the amount of infrastructure that would be utilized in a particular place if it existed.

Much of the point of public planning is that in practice that definition of need isn't one that really creates fantastic outcomes.

rplst84• 11 years ago

I think in some major metro areas, the road capacity is vastly behind what is needed. My commute is is 26 miles of limited access highway that occurs at nearly 1/3 to 1/2 of the posted speed limit.

The only reason there is induced demand is that the infrastructure is too small to support the way our cities and metro areas have evolved. Maybe the way they have evolved is a product of the Eisenhower Interstate highway system, but we're already invested in that infrastructure. It would take an inordinate amount of money, resources, and effort to relocate and redesign our cities than to just build the correct size (and number) of highways to support the population.

In addition - one thing that it seems highway planners rarely plan correctly for is growth. The population of the Washington DC metro area has grown from about 3 million in 1980 to over 6 million currently. Many of the highways are nearly the same size over that span.

angdis2• 11 years ago

DC actually did plan for growth when they build the metro. Everyday it transports a staggering number of people which would be intractable for ANY highway system if these same people drove.

What they failed to account for, however, is the growth of exburbs like Ashburn VA and other places even further out like Frederick MD.

These remote places are built by developers who literally put ZERO thought into infrastructure and what will happen to traffic and many other things when thousands of well-paid people move into their McMansions in the middle of nowhere.

They just buy up farmland from farmers who want to retire, sell a fake dream of idyllic rural living, plop down a bunch of cookie-cutter houses, then take the money and do all over again somewhere else. People have been finally getting wise to this anti-pattern (it was known in Maryland since the 90's) and the citylab article is an example.

andys6276• 11 years ago

Federal, state, and local governments have ignored "induced demand" for 50 years and the result has been endless highway building. This is an effective subsidy for "sprawl" and is a huge driver of why the US built environment looks the way it does. Most of the US is "car dependent" - ie you must have a car to reasonably participate in the city - yes there are buses but they are not as convenient as having a car, yes there are bike lanes but they are dangerous and sparse.

I think the thing that we have to get through our heads is that sprawl is the result of many subsidies - NOT just peoples' preference to live that way. Take a look at any place where zoning hasn't required such high parking or low maximum densities; any place where government housing loan guarantees were equally available to dense developments as new single family home developments; or any place where governments have made reasonable attempt to add the cost of negative externalities of driving to fuel taxes. You'll see a lot less driving and a lot more walking, transit, and biking. For example - Canada or Spain.

Every time one of these articles comes up on here there are lots of Bay Area folks saying "but I like to drive my own car". That is fine, but don't make everyone else subsidize it.

We've dug ourselves into a major hole with car dependence. Lots of cities are digging out and building density especially in their abandoned downtowns - this is doubly amazing considering how stacked the deck is against them.

hammock• 11 years ago

Just to be clear for all the readers, the alternative to falling into the induced demand trap by building more roads, is to improve public transportation infrastructure. Such improvement has been shown, perhaps counterintuitively, to have the biggest effect on road traffic.

The shorter your commute via public transportation, the less traffic on the road.

With respect to the subsidization effort, there is very little transportation infrastructure in developed countries that is not subsidized in some way - though I'd like to see a discussion of that.

I can think of mining towns, logging roads, private university campuses, Disney World...what else?

jerf3• 11 years ago

Suppose you want to build a railway from TownA to TownB. It's ten miles and you can prove in every conceivable way that it will be profitable for both you and the two towns.

You still can't, because in a society with strong property rights, all the land is owned by somebody, and unless you're out west where one person might own the vast majority of the requisite right-of-way, you have basically no chance of every acquiring all the rights at any reasonable price. Geometry is conspiring to incentivize people in the middle of any given path to hold out for more money by holding the prospect of failure over your head. Reality has even shown that many people irrationally overestimate how much they can squeeze from you, so you realistically face the prospect of many people believing they are the last holdout and trying to squeeze you for so much that it renders the entire project economical.

Thus, the only conceivably private public transport must run on the roads anyhow. Anything else is going to be created by some form of government action; in some sense calling it "subsidized" is almost misleading in that it's entirely created by the government in the first place, even if half-privatized after the fact.

All the instances you name are situations in which one singular entity owns all the land, and thus doesn't have the problem of having to coordinate with dozens of irrational people all trying to squeeze you for cash.

pmorici• 11 years ago

Historically trains, and street cars were privately funded and operated in a lot of US cities. For example in the early 1900's Baltimore was one of the largest cities in the US and had a massive street car network that was privately operated.

https://en.wikipedia.org/wiki/History_of_MTA_Maryland#Baltim...

c3534l2• 11 years ago

Transportation is a classic externality. The costs of building infrastructure are direct, while the benefits diffuse. You tend only to see that sort of behavior by monopolies, like the examples you mentioned applying to companies that own very large swaths of land. You can sometimes see this behavior in R&D, too. Bell spent a lot of money on research and development because they knew as the only major telephone company they would be the only ones to benefit.

Shivetya• 11 years ago

Sprawl isn't simply because of subsidies, a lot of it has to with people changing jobs and ending up further from work or having work relocate and doing the same. Throw in trying to live closer to work in many towns is impractical because of cost.

When it comes to mass transit in cities, quit blowing money on trains. For some odd reason politicians and many people are hung up on light rail and it has the worst cost structure of all mass transit options. It isn't flexible and its cost per mile is staggering let alone the cost of maintenance.

we have no hole dug on our dependence on cars. The only hole is that a lot of road building and maintenance is politically driven as does not fix a problem but instead buy votes in politically sensitive areas.

bryanlarsen2• 11 years ago

What's the alternative to light rail?

To substantially reduce road traffic, you need to offer people an alternative that is cheaper and/or faster and/or more convenient.

Since most of the cost of a car is sunk costs (you have to pay your insurance & depreciation on your car whether you use it to commute or not), if there's free parking at work the car is going to be the cheapest option for most people.

So either you have to substantially increase the cost of driving (aka tolls), or you have to give them an option that's faster and/or more convenient. A bus using the same roads as cars can never be faster or more convenient.

Bus rapid transit (buses on dedicated roadways) may be an option, but a good BRT (aka one without traffic lights) isn't substantially cheaper than LRT.

maxsilver3• 11 years ago

For some odd reason politicians and many people are hung up on light rail and it has the worst cost structure of all mass transit options.

For many people, Light Rail (or trains / subways) are the only decent mass transit they have ever experienced in the US.

Every single major and minor city has a bus system. Most of them are nearly useless, often intentionally so by design. It's natural for people to demand something useful, and light rail is nearly universally more useful than busing (including BRT) in any given market.

It isn't flexible and its cost per mile is staggering let alone the cost of maintenance.

Those are benefits of light rail, not drawbacks. The higher costs and inflexibility of light rail represents an authentic long-term commitment to good useful transit in that area.

To replicate that value with a Bus system requires you to build grade separated, dedicated right of way. Which is where 90% of Light Rail's cost comes from. So if your going to spend that money, you might as well put in real Light Rail and get all of the benefit.

ryandrake2• 11 years ago

What's the solution, if not more trains or more frequent train service? Take a commute to the South Bay from my neighborhood: a little over 50 miles on three interstate highways (I-580, I-680, I-880), which takes 2+ hours during rush hours, due entirely to road congestion. How do you fix this? Bike lanes?

mcooley• 11 years ago

It isn't flexible

That part may be a feature. A bus stop next to your apartment building might be gone next week, but a light rail station is staying put and developers can more confidently build "transit-oriented" neighborhoods (denser, less parking, etc.).

c3534l2• 11 years ago

Yes, but a good public transportation system usually requires heavy government support and sponsorship. The subsidies to suburban, sprawling neighborhoods are much more difficult to see than the direct costs associated with building and maintaining public transportation. The perceived quality of public transportation also have a big impact. It's a very difficult thing to do politically, so I'm more surprised by the areas that have managed to create good transit than places that have failed to do so.

hueving5• 11 years ago

Every time one of these articles comes up on here there are lots of Bay Area folks saying "but I like to drive my own car". That is fine, but don't make everyone else subsidize it.

That cuts both ways. There are very few subway systems in the world that are self-sustaining. You can't just say to not subsidize one way of life while demanding people subsidize another.

throwaway2048• 11 years ago

Why? It's perfectly fine to beleive that one is more harmful in various ways than another.

mikeash6• 11 years ago

Sure, let's just bring public transit subsidies up to the same level as car subsidies, then.

colin_jack• 11 years ago

I guess the obvious argument would be that its worth subsidizing public transport as it has additional benefits, in terms of the environment and being open to the entire population not just those who are able and can afford to drive.

dragonwriter• 11 years ago

You can't just say to not subsidize one way of life while demanding people subsidize another.

You absolutely can. And you absolutely should, if the one you say should not be subsidized has net social cost compared to the other.

cpursley• 11 years ago

I've been saying this for years: federal interstates have contributed to sprawl by effectively subsidizing both land and driving. It creates all sorts of disincentives.

WildUtah• 11 years ago

"This is an effective subsidy for "sprawl" and is a huge driver of why the US built environment looks the way it does."

To be fair, the subsidies are not mostly in highway building. Suburban feeder style streets (4-8 lanes with lights, turn lanes) get bigger subsidies and drive more sprawl. But even those are a smallish factor.

The big subsidy is free and cheap parking. Most American cities require that businesses and new homes provide enough parking for everyone who ever wants to come to park free. That's a subsidy equivalent to about $10-30k per car per year, depending on your local real estate costs. The outright majority of space in real estate development in the USA is devoted to satisfying this centralized Soviet style command-and-control mandate.

Countries with the most free market real estate development in the free world, like Japan, still build freeways. In fact, Japan has a silly amount of freeways because you don't even need or want a car usually. Those countries are different because they require a lot less parking.

So the induced demand and highway subsidy question is not the most central to the car dependence and sprawl question. Parking mandates are much more important to the way life is actually lived in America.

pjc503• 11 years ago

Sprawl in the US, and the lack of public transport, is influenced by the legacy of racism. There are still plenty of people who will oppose public transport on this basis.

andys6276• 11 years ago

This is a huge issue IMHO. It's interesting to see comparisons of different transit solutions by how many people they get to switch modes. For example buses usually are very cheap but get few people to switch. Streetcars on the same route are much more expensive but get lots of people to switch.

klagermkii• 11 years ago

I really dislike "induced demand" as a reason to maintain a terrible experience of a desired product or service. Increase fuel taxes or even do demand charging, but don't have this thing where you make a car trip take three times longer because it discourages people from using their cars.

randallsquared• 11 years ago

I think the argument isn't "let's not improve things because people will use things more" but "let's not spend resources for little improvement". The induced demand argument suggests that the pain and utility of traffic are in equilibrium, and that there's so much latent demand that no feasible amount of pavement will reduce the pain appreciably. It seems to me of a similar genre to studies showing that safety equipment increases risky behavior.

awjr5• 11 years ago

That's the point, "induced demand" is simply the fact of making it easier to travel by car, encourages more people to choose to travel by car. It is not that the trip takes three times as long, it's the fact, they built a wider road and the journey took half as long, prior to the road being widened.

You cannot solve this by building more roads. You solve it by putting roads on a "road diet" https://en.wikipedia.org/wiki/Road_diet enabling modal share https://en.wikipedia.org/wiki/Modal_share . You create segregated space for walking, for cycling. You prioritise public transport.

You want more people to choose any other option, other than the car. This, however, is hard when traffic modelling still focuses on traffic flow (maximising car throughput) over modal share.

In the UK, it estimated that the school run is 20%-25% of rush hour. Our road design precludes kids cycling to school.

timthorn• 11 years ago

Our road design precludes kids cycling to school

No, there are plenty of children who cycle to school and in safety in the UK. The bigger issue is parents' fears of abduction and/or traffic.

Agustus2• 11 years ago

No, travel demand modeling includes transit shares and modeling.

More roads are a fantastic solution for encouraging mobility of individuals. Yes, it is difficult from a group planning point of view, but think about it from the users point of view. There is a single dad who is restricted by her availability of time to a thirty minute commute window. If he has no available car, he is forced to a bus route based job, or bicycle / walking distance job. Locations for bus routes are chosen by top-down planning based on productions and attractions, with a preference for utilization based on larger employers, think hospital and hospitality. The buses drive the single dad to a certain area and precludes him from looking for jobs in non-bus route areas. You are forcing an individual to choose a non-ideal job based on a push for modal share and the "Planners" basis of what is best, not the individual.

Road diets are dangerous for the populace. Look at Los Angeles current push for road diets that will decrease the levels of service across the city from 18% failure to 30% failure and the warnings that the emergency services say about the corresponding decrease in response times.

The school run in the mornings is a good thing to focus on, here in the United States, we force the kids onto a crazy schedule of arriving in class before 8:00am.

mattheusser• 11 years ago

Jevon's Law. Google it.

nashashmi• 11 years ago

I have started taking every article of complaint from citylab with a grain of salt. It always seems like there is an agenda with these articles.

In this case, they are trying to curb the building of roads. I do not know how that helps. Alleviating traffic and bringing increased capacity to roads helps spur economic activity.

The Big Dig Project on the Central Artery in Boston helped alleviate traffic and resume economic growth in an area where it had stalled. The capacity of the artery is expected to be fully realized by 2050.

In NJ, we are always stuck in traffic. And that is the main reason why NJ's economy has stalled. No more room for growth.

The point of the article and citylab's purpose is probably to direct more use of public transportation. But likewise, the more public transportation you have, the more use you will have there too.

I really don't see the point of this article.

trgn3• 11 years ago

The point is that building more roads doesn't reduce congestion. This is because the number of car trips increases as well. As the supply of roads grow, the demand for car trips goes up as well, to the benefit of no one.

It is definitely an editorial decision of Citylab to evangelize this finding. But in this case, not in a mendacious way, more in an exasperating i told you once i told you a million times kind of way.

That NJs economy stalled due to not having enough roads is a conjecture.

You don't need physical room for economic growth (well, I'd say in the US you don't). The US is incredibly wasteful, to the point of it being obscene, with its physical space. The upside is dubious. But the negative results of car slavery are clear: it excludes children and seniors of being independently mobile, it creates a terribly unattractive environment, high speed roads - aka car sewers - are a killer on property values since nobody wants to live next to on, driving claims more than 30000 lives per year in this country alone.

Cars have benefits though!!! I have three, should that factoid help convince you. But they work best in a handful of use cases: longer trips, hauling stuff, recreational driving in the country, ... Basically, what the commercials show you. But when you're shackled to them to do daily errands that you could just as well do on your own two feet if only the built environment wasn't so hostile to humans, they are terrible.

woah• 11 years ago

Why should I pay for you to drive?

Agustus2• 11 years ago

You do not. We all pay for our roads through gas taxes. The real question becomes then: Why should I pay for you to ride the bus?

dumbmatter2• 11 years ago

Adding 10 percent more road capacity leads to 3-6 percent more vehicle miles in the near term and 6-10 percent more over many years.

So... sounds like less traffic. Wonder why the title says "more traffic".

Some of the cars on a new highway lane have simply relocated from a slower alternative route. But many are entirely new. They reflect leisure trips that often go unmade in bad traffic, or drivers who once used transit or carpooled, or shifting development patterns, and so on.

Those all sound like good things. The point of roads is to use them. So people use them to have a shorter commute, or live a bit further away from work to lower rent, etc etc etc.

What is the actual problem? Did anyone actually expect that building more roads would lead to no increase in road usage?

codeulike• 11 years ago

Because there are alternatives that also increase people's mobility, as 'hammock' wrote below: "the alternative to falling into the induced demand trap by building more roads, is to improve public transportation infrastructure. Such improvement has been shown, perhaps counterintuitively, to have the biggest effect on road traffic."

thehenster• 11 years ago

"Did anyone actually expect that building more roads would lead to no increase in road usage?"

I think that's exactly it.

Perhaps all road building initiatives should be publicised as short term congestion relief and long term preference of cars over other forms of transport.

lhopki018• 11 years ago

The problem is you get into an endless cycle of adding more and more road capacity and still ending up with the same amount of congestion. If you invest that money in public transport or cycle infrastructure you end up lowering congestion and speeding up everyone's movement including those that still want to drive.

dumbmatter2• 11 years ago

I still don't see why "Adding 10 percent more road capacity leads to 3-6 percent more vehicle miles in the near term and 6-10 percent more over many years" is being interpreted as "ending up with the same amount of congestion".

If public transit or bike lanes would provide a better benefit for the same cost, then I would support them. But that's a separate and complicated discussion. Instead, this article seems designed to mislead people into thinking that expanding roads has literally no benefit, when obviously it does even if congestion remained the same (which it doesn't).

Maybe I'm too cynical...

jessriedel• 11 years ago

Yes, when you build useful things, people generally use them. Consider: "The parks are too crowded. But if we build parks, this mostly just lowers the density of park-goers in the short term. In the long term, people move to live near the parks and use the parks more, so that the density of park-goers rises again, and we loose most of the benefit!"

There's lots of constructive arguments to be had about the relative benefits of investment in roads vs. rail vs. whatever, and tons of good criticism to level against subsidies and un-taxed externalities (for all those options). But arguments complaining about the "endless cycle" of building useful things that subsequently get used are silly. This lowers the quality of the conversation about public transit, making it more difficult to convince others of the relative merits.

moron4hire• 11 years ago

Should we be focused on traffic--i.e. the density of vehicles on the road--or throughput of travelers? Because if you don't build roads, and let traffic build too high, there is a point where congestion becomes a major impediment and throughput plummets.

xemdetia• 11 years ago

Being someone who is familiar the Connecticut segments of the highways mentioned it seems much like a false comparision. I-95 in that segment is the major artery from the US west of New Jersey and New York to Boston and most of the northeast, and I-84 is much the same (except it goes through Hartford and is consistently a disaster).

Most of the segments of I-95 and I-84 they will want to improve already are 2-lanes and are frequently stopped due to accidents. While I agree with the article's claim that the increase in economic activity in those areas is dubious it's something that is needed. If anything it's going to increase tourism traffic to points north as well as Connecticut as there is already plenty of traffic from NYC/NJ through to other coastal areas (RI, Cape Cod). Also this includes traffic from points north to the Connecticut casinos that are in the heart of the state which is another major inflow.

I just don't understand if the roads CalTrans are describing and the author is trying to demonstrate are really equivalent, where 'thru' traffic is just as vital as in-state to in-state traffic.

roflchoppa• 11 years ago

Yeah not sure if I'm down for larger highway 84, where are they going to push out into? Ardenwood Farms? The Fremont city board already has told residents that it does not plan to slow down the building of new homes in the area. Which is a big issue because current public schools cannot fit all these students here... 1LTC says that y'all are being paid for by the same development companies from SF to build housing here.

vdnkh• 11 years ago

I live in NJ, in the shadow of NYC, and commute to work every day on some of the busiest roads in the state. The real problem I see are trucks. Big stupid semi-trailers and dumptrucks, queued up by the dozens with shipments fresh from the nearby *ports. Trucks, which exceed the lane space of a bus yet carry a single person. Sitting comfy in the left lane doing 15 under while traffic piles up behind them, another semi alongside blocking any traffic.

California's DOT Admits That More Roads Mean More Traffic

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