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.
"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.
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?
>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.
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.
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.
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.
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.
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?
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.
"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.
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."
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.
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 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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
[+] [-] andys627|10 years ago|reply
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.
[+] [-] WildUtah|10 years ago|reply
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.
[+] [-] hammock|10 years ago|reply
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?
[+] [-] hueving|10 years ago|reply
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.
[+] [-] pjc50|10 years ago|reply
[+] [-] c3534l|10 years ago|reply
[+] [-] cpursley|10 years ago|reply
[+] [-] Shivetya|10 years ago|reply
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.
[+] [-] unknown|10 years ago|reply
[deleted]
[+] [-] dumbmatter|10 years ago|reply
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?
[+] [-] lhopki01|10 years ago|reply
[+] [-] thehenster|10 years ago|reply
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.
[+] [-] codeulike|10 years ago|reply
[+] [-] klagermkii|10 years ago|reply
[+] [-] awjr|10 years ago|reply
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.
[+] [-] randallsquared|10 years ago|reply
[+] [-] nashashmi|10 years ago|reply
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.
[+] [-] trgn|10 years ago|reply
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|10 years ago|reply
[+] [-] unknown|10 years ago|reply
[deleted]
[+] [-] xemdetia|10 years ago|reply
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.
[+] [-] moron4hire|10 years ago|reply
[+] [-] vdnkh|10 years ago|reply
[+] [-] roflchoppa|10 years ago|reply
[+] [-] crystaln|10 years ago|reply
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.
[+] [-] dsfyu404ed|10 years ago|reply
[+] [-] revelation|10 years ago|reply
[+] [-] pfortuny|10 years ago|reply
[+] [-] rplst8|10 years ago|reply
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.
[+] [-] mattheusser|10 years ago|reply