Widening Highways Doesn't Fix Traffic. So Why Do We Keep Doing It?

[edale]

Originally Posted by Innsertnamehere

To answer your first question: yes, absolutely. And also: Induced demand has limits, and isn't in itself a bad thing. Inducing new trips is inducing new economic activities and inducing improved connections for people. Ultimately those more cars are allowing more people to go to the places they want to go, when they want to go.

Often the "no improvement" travel time statistic is also only for peak rush hour, when a roadway operates at it's absolute worst. Road widening projects often cannot accommodate peak-hour demand as it is simply so high, especially on roads which are severely congested and see significant amounts of trip-avoidance in peak periods. A widening on that kind or road will still result in substantial reductions in congestion in off-peak periods. At the very least, it allows people to make their trips at more preferred times as they don't have to wait out rush hour any longer.

I know around the GTA, all highways which have been widened in the last 2 decades operate substantially better than they did before, even if they perhaps still bunch up at rush hour.

Where the discussion needs to be held is what kinds of trips we want to induce - do we really want to induce new vehicle trips into a downtown core, for example? It's better to build transit for that sort of condition. It's a lot more nuanced than just "road widening = bad".

Good post. I agree with what you're saying here.

There is one US city where I think the freeway and transit infrastructure is woefully undersized-- Pittsburgh. I know the topography makes things difficult, but they have a very limited freeway network, and the ones that are there are mostly 2 lane things that I'd say closer resemble a parkway than a true freeway. Pittsburgh has a decent transit network with the T and some true BRT, but it's not nearly robust enough to make up for the undersized road network, imo. It makes mobility there really challenging, and I think has probably held the metro back a bit.

[Yuri]

Originally Posted by Innsertnamehere

To answer your first question: yes, absolutely. And also: Induced demand has limits, and isn't in itself a bad thing. Inducing new trips is inducing new economic activities and inducing improved connections for people. Ultimately those more cars are allowing more people to go to the places they want to go, when they want to go.

Often the "no improvement" travel time statistic is also only for peak rush hour, when a roadway operates at it's absolute worst. Road widening projects often cannot accommodate peak-hour demand as it is simply so high, especially on roads which are severely congested and see significant amounts of trip-avoidance in peak periods. A widening on that kind or road will still result in substantial reductions in congestion in off-peak periods. At the very least, it allows people to make their trips at more preferred times as they don't have to wait out rush hour any longer.

I know around the GTA, all highways which have been widened in the last 2 decades operate substantially better than they did before, even if they perhaps still bunch up at rush hour.

Where the discussion needs to be held is what kinds of trips we want to induce - do we really want to induce new vehicle trips into a downtown core, for example? It's better to build transit for that sort of condition. It's a lot more nuanced than just "road widening = bad".

Budgets are limited though. São Paulo invested heavily on car infrastructure for decades and as result transit moved slowly. That changed radically around 2000 and since then tens of billions were invested on public transit and virtually now new car-related infrastructure inside the city. Outside it, the 100 mile-long ringroad is almost completely but it has a more regional character.

If you have a choice, go with transit. And needless to say a city organized around transit is much more pleasant than driving through endless suburbs and those hideous strip malls.

[TWAK]

We need some lanes up here...basically all the state highways are one-lane roads and it hurts economic activity.

[badrunner]

Originally Posted by TWAK

We need some lanes up here...basically all the state highways are one-lane roads and it hurts economic activity.

But you'll just be inducing demand so it's pointless

[muppet]

a reminder that the Netherlands was a carcentric nation as recently as the 70s and 80s, but the traffic deaths and political empowerment to complain about them slowly led to to the set up of the vast biking infrastructure that converted the whole nation after 2 decades. It won't happen overnight but piecemeal, with growing impetus.

[TWAK]

Originally Posted by badrunner

But you'll just be inducing demand so it's pointless

The freeway we do have (only 8 miles long) is generally empty and way below capacity, but that could happen on the southeast side of the lake if built. The the county loses about 1 billion a year in economic activity (supposedly) due to the lack of transportation options for manufacturing and ect. There's not even a rail line, which would be nice as well...

[Innsertnamehere]

Originally Posted by muppet

a reminder that the Netherlands was a carcentric nation as recently as the 70s and 80s, but the traffic deaths and political empowerment to complain about them slowly led to to the set up of the vast biking infrastructure that converted the whole nation after 2 decades. It won't happen overnight but piecemeal, with growing impetus.

I encourage you to look at the kind of work the Netherlands has done to its freeway network over the last decade. It has one of the largest and most complex freeways systems on the planet, and much of it was built in the last few years.

It’s almost like these kinds of things don’t need to be so black and white. You can have efficient car movement and still provide alternatives and create attractive cities.

[iheartthed]

Originally Posted by Innsertnamehere

I encourage you to look at the kind of work the Netherlands has done to its freeway network over the last decade. It has one of the largest and most complex freeways systems on the planet, and much of it was built in the last few years.

It’s almost like these kinds of things don’t need to be so black and white. You can have efficient car movement and still provide alternatives and create attractive cities.

I've only been to Amsterdam, but there certainly did not seem to be a lot of urban freeways there by U.S. standards. They also didn't have stroads.

[Crawford]

Originally Posted by Innsertnamehere

It’s almost like these kinds of things don’t need to be so black and white. You can have efficient car movement and still provide alternatives and create attractive cities.

I'm not sure that's true. At least in the North American context, "efficient car movement" pretty much guarantees crappy cities. It means people will live car-centered lifestyles, which is incompatible with good urbanity.

Major cities shouldn't have "efficient car movement". That usually means something is seriously wrong.

[Innsertnamehere]

Originally Posted by iheartthed

I've only been to Amsterdam, but there certainly did not seem to be a lot of urban freeways there by U.S. standards. They also didn't have stroads.

Not in the immediate core, no.

some major highway projects completed in the last decade in the netherlands:

Large collector distributor highway outside of amsterdam:

https://www.google.com/maps/@52.3244.../data=!3m1!1e3

New freeway between Rotterdam and the Hague:
https://www.google.com/maps/@51.9486.../data=!3m1!1e3

Widening of a major highway to 10 lanes near the Amsterdam Airport:
https://www.google.com/maps/@52.2480.../data=!3m1!1e3

A new underground urban expressway immediately adjacent to downtown Maastricht:

https://www.google.com/maps/@50.8356.../data=!3m1!1e3



Some more currently underway - these are both new construction urban freeways:

A new tunnelled connection to the Port of Rotterdam:
https://www.google.com/maps/@51.9028.../data=!3m1!1e3

A new connection in suburban Rotterdam avoiding a major freeway pinch point:
https://www.google.com/maps/@51.9573.../data=!3m1!1e3

The Netherlands definitely has large arterial roads as well, they are just better about not treating them as "main streets" at the same time.

A typical Dutch arterial road looks more like this - 4 lanes with a grass median, access controlled, dedicated cycling facility beside it. Still very excellent at moving cars. The difference is that they don't ram these right through town centres like the US does.

https://www.google.com/maps/@51.9578.../data=!3m1!1e3

[Innsertnamehere]

Originally Posted by Crawford

I'm not sure that's true. At least in the North American context, "efficient car movement" pretty much guarantees crappy cities. It means people will live car-centered lifestyles, which is incompatible with good urbanity.

Major cities shouldn't have "efficient car movement". That usually means something is seriously wrong.

in and out of downtowns, not so much, I agree. Not a good formula for a healthy downtown centre.

In suburban areas and for regional transportation? Highways are absolutely critical.

As I said initially - we have to understand what infrastructure choices we are making and where which kinds of infrastructure makes sense. The Dutch model is to generally push traffic to highways and limited access roads, which makes driving much safer and takes traffic away from pedestrian areas. Which is why tourists who don't rent cars when visiting the Netherlands often think there are very few cars, because they simply don't see them. The reality is that much of the Netherlands, especially outside of the major cities, sees only marginally lower rates of automotive ownership and use than in North America.

I am generally a big supporter of building large highways and small local streets. Stroads are terrible pieces of infrastructure that work for nobody. Freeways are generally excellent pieces of infrastructure however, other than where they shovel large numbers of cars into downtowns at the expense of transit. which in turn causes downtowns to become traffic sewers and parking lots.

The original point of this thread however was discussing the concept of Induced Demand - which while an actual phenomenon, is generally severely misunderstood by the general public and is absolutely not what the OP article implied which is that any and all road projects are entirely pointless.

[iheartthed]

Originally Posted by Innsertnamehere

Not in the immediate core, no.

some major highway projects completed in the last decade in the netherlands:

Large collector distributor highway outside of amsterdam:

https://www.google.com/maps/@52.3244.../data=!3m1!1e3

New freeway between Rotterdam and the Hague:
https://www.google.com/maps/@51.9486.../data=!3m1!1e3

Widening of a major highway to 10 lanes near the Amsterdam Airport:
https://www.google.com/maps/@52.2480.../data=!3m1!1e3

A new underground urban expressway immediately adjacent to downtown Maastricht:

https://www.google.com/maps/@50.8356.../data=!3m1!1e3



Some more currently underway - these are both new construction urban freeways:

A new tunnelled connection to the Port of Rotterdam:
https://www.google.com/maps/@51.9028.../data=!3m1!1e3

A new connection in suburban Rotterdam avoiding a major freeway pinch point:
https://www.google.com/maps/@51.9573.../data=!3m1!1e3

The Netherlands definitely has large arterial roads as well, they are just better about not treating them as "main streets" at the same time.

A typical Dutch arterial road looks more like this - 4 lanes with a grass median, access controlled, dedicated cycling facility beside it. Still very excellent at moving cars. The difference is that they don't ram these right through town centres like the US does.

https://www.google.com/maps/@51.9578.../data=!3m1!1e3

They also put money into mass transit, unlike the vast majority of U.S. cities. I can't think of any U.S. city that should be spending a single dime on adding traffic lanes instead of building rail transit.

[badrunner]

The Netherlands also has one of the few four level stack interchanges in Europe just outside the Hague: https://www.google.com/maps/@52.0612.../data=!3m1!1e3

Maybe the prettiest one in Europe? I would say overall it has very impressive autobahn-level highways.

[Nouvellecosse]

Originally Posted by Innsertnamehere

I encourage you to look at the kind of work the Netherlands has done to its freeway network over the last decade. It has one of the largest and most complex freeways systems on the planet, and much of it was built in the last few years.

It’s almost like these kinds of things don’t need to be so black and white. You can have efficient car movement and still provide alternatives and create attractive cities.

You can definitely have efficient car movement in metro areas if achieved through user fees like road and congestion tolls, especially when adjusted to ensure the optimal traffic volumes. But otherwise congestion will be a perpetual problem that isn't feasible to solve by expanding the road infrastructure.

Even the most cursory research shows this to be true of the Netherands as well. There's a whole section for congestion in the "Road transport in the Netherlands" wiki page" which states the following:

"Traffic congestion is common in the Netherlands. The high population density generates significant traffic volumes on both motorways and regular highways. Most congestion occurs in the Randstad, but congestion is a daily structural problem around almost all larger cities. The Dutch motorway network may be one of the densest in the world, but many motorways are lacking sufficient capacity, and many bottlenecks of 4-lane motorways are present throughout the Netherlands. Traffic volumes are higher than in other European countries, comparable to those of Germany and the United Kingdom."

In other words, even with this proportionately huge road network (one of the world's densest) and even with all it's public transport, it the Netherlands hasn't managed to built its way out of road congestion. I agree that the issue isn't totally black and white, but if anything it's closer to being black and white than most people assume.

[Crawford]

I've driven in Netherlands, and it's more or less like Germany. Very good roads, but transit and pedestrian-oriented. Nothing really like North America, where there are few exceptions to complete auto domination.

[Innsertnamehere]

Netherlands has peak hour congestion absolutely, That is not really practical to avoid in major cities.

Ultimately this is what congestion is like in the Netherlands at 6:40pm on a weekday however - a few accident related traffic areas, but no volume-related congestion whatsoever (every red area has an accident report shown).



That's a pretty solid, efficient road network overall. Obviously there will be congestion at 5pm.

Again, I'm not arguing "highway widenings or bust" - just that we need a more nuanced look at infrastructure spending here. The formula shouldn't be "all money needs to go to widening roads" just like it shouldn't be "all money needs to go to transit". It's the same thing with induced demand - it's not always a bad thing, it's not always entirely true, and it absolutely does not automatically negate any road infrastructure project's benefits.

The Netherlands is great at finding this balance - they build roads where roads make sense and transit where transit makes sense.

[iheartthed]

Originally Posted by Innsertnamehere

That's a pretty solid, efficient road network overall. Obviously there will be congestion at 5pm.

Again, I'm not arguing "highway widenings or bust" - just that we need a more nuanced look at infrastructure spending here. The formula shouldn't be "all money needs to go to widening roads" just like it shouldn't be "all money needs to go to transit". It's the same thing with induced demand - it's not always a bad thing, it's not always entirely true, and it absolutely does not automatically negate any road infrastructure project's benefits.

The Netherlands is great at finding this balance - they build roads where roads make sense and transit where transit makes sense.

So this doesn't really rebut why the Netherlands was mentioned. They consider various modes of transit when making infrastructure decisions instead of just only considering cars. In 95% of the US, cars are the only serious consideration.

[MolsonExport]

The monster known as the 401 (the busiest in North America, and perhaps the world) was once 4 lanes wide (now 18 lanes through Toronto). Partly induced demand, mostly due to population growth. Rush hour was equally a nightmare in 1962 when it was 4 lanes, and now when it is 18 lanes.

[MolsonExport]

Motor Vehicles per 1000 population, # vehicles, year
Netherlands 588 10,248,388 2020
United States 890 295,836,000 2022

obviously that doesn't tell the whole story, nor even most of it. It is more about how much people drive.

[iheartthed]

Originally Posted by MolsonExport

To be fair, the Dutch were pretty much the only western country with urban bike lanes in 2010. I'm sure they're still way ahead of everyone else but that gap has certainly closed over the past decade.