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Roads: GTA West Corridor—Highway 413


There is a quote from the government two thirds of the way down when asked directly about induced demand.

Traffic will be diverted for the first year or two, but historically people bend their behaviour to the available infrastructure. When a faster route opens up people change their behaviour to use it. Within a couple of years it's no longer the faster route and there are now more cars in the whole system. As far as I know there isn't an example of an urban freeway where this doesn't happen. There might be exceptions that I am unaware of though.
how come papers can't get a quote from an actual transportation professional on this then? The only ones they are quoting are misunderstood academic papers and planners who work in environmental planning and not transportation. There's a reason for that.

Induced demand is real but it doesn't mean new road infrastructure is pointless, or that induced demand automatically means 100% of new road infrastructure automatically triggers an equal amount of trips and results in absolutely 0 time savings.
 

There is a quote from the government two thirds of the way down when asked directly about induced demand.

Traffic will be diverted for the first year or two, but historically people bend their behaviour to the available infrastructure. When a faster route opens up people change their behaviour to use it. Within a couple of years it's no longer the faster route and there are now more cars in the whole system. As far as I know there isn't an example of an urban freeway where this doesn't happen. There might be exceptions that I am unaware of though.

The article states, "Asked whether the government’s estimates take into account induced demand, Jordanna Colwill, the minister’s spokesperson, said they capture “demand that would shift to the new highways from other modes or other adjacent roads.” That’s different from factoring in induced demand, under which the new highway would be expected to increase the overall number of cars on the network, not just draw them from other roadways."

I am a fan of Ben Spurr, but the author is wrong. Capturing shifts in modes would exactly reflect an increase in the overall number of cars in the network, which is what the model is doing. The increase in cars just isn't as high as those touting the induced demand boogeyman would expect (i.e., not enough to make the whole project pointless). Studies show that the addition of Highway 413 would add at most a total of 1000 vehicles to the GTHA by 2041. That's the induced demand for the corridor.

So I wouldn't call that an admission of induced demand not being considered in the modelling process, but rather the author's misunderstanding of the concept. What is induced demand? It's the latent and newly generated demand resulting from a new piece of infrastructure. Capturing shift in mode and route selection is a huge part of what induced demand is and the model reflects those things. The article also does a poor job of explaining the concept as well. Rather than explaining what it is in real terms, the author just states the end result of roads becoming as congested as they were before. That's all good and well, but provides no substance as to why this occurs. Are drivers just out driving all evening because they have a new road to drive on? Or is there a huge amount of latent demand pent up which this new infrastructure is now accommodating?

Whether time time savings benefit wears off in the long run is kind of irrelevant, as the goal is to provide benefits compared to a no build scenario, and the 413 and other auto capacity will always provide time savings compared to that. If we don't build, travel times in the region deteriorate and become even more severe. If we do build and over time end up with the same travel times but with twice as many trips accommodated, is that the same as being back where we started?
 
how come papers can't get a quote from an actual transportation professional on this then? The only ones they are quoting are misunderstood academic papers and planners who work in environmental planning and not transportation. There's a reason for that.

Induced demand is real but it doesn't mean new road infrastructure is pointless, or that induced demand automatically means 100% of new road infrastructure automatically triggers an equal amount of trips and results in absolutely 0 time savings.
It would seem far fetched to me that all the experts who oppose this are playing politics and misinformed. Even the guy at the end of the article that has a more favourable 413 opinion believes when all factors are considered it it still a bad idea. At some point they can't all be shrugged off as environmentalists with an agenda.
I am a fan of Ben Spurr, but the author is wrong. Capturing shifts in modes would exactly reflect an increase in the overall number of cars in the network, which is what the model is doing. The increase in cars just isn't as high as those touting the induced demand boogeyman would expect (i.e., not enough to make the whole project pointless). Studies show that the addition of Highway 413 would add at most a total of 1000 vehicles to the GTHA by 2041. That's the induced demand for the corridor.
I honestly don't think he is misunderstanding anything, and I would love to see the studies you are referring to. If you could send a link or some keywords that I could search I would love to give it a read.
Whether time time savings benefit wears off in the long run is kind of irrelevant, as the goal is to provide benefits compared to a no build scenario, and the 413 and other auto capacity will always provide time savings compared to that. If we don't build, travel times in the region deteriorate and become even more severe. If we do build and over time end up with the same travel times but with twice as many trips accommodated, is that the same as being back where we started?
By "long run" we should establish that were talking 3-5 years. And it's exactly the argument that a no build scenario would be better as the con's outweigh the pro's. It seems to be taken as a given that these extra car trips will exist no matter what and if we don't increase road capacity there will be "carmageddon." This isn't inevitable and real world case studies prove the opposite. Just as induced demand is an important factor to consider, "reduced demand" or "traffic evaporation" is a studied phenomenon as well. Loads of freeways have been removed without an increase in traffic, and some have led to improved city traffic overall. Another theory here is the Braess's paradox.
 
how come papers can't get a quote from an actual transportation professional on this then? The only ones they are quoting are misunderstood academic papers and planners who work in environmental planning and not transportation. There's a reason for that.

Induced demand is real but it doesn't mean new road infrastructure is pointless, or that induced demand automatically means 100% of new road infrastructure automatically triggers an equal amount of trips and results in absolutely 0 time savings.
Why must someone cite experts for a principle (in this case induced demand) that is a proven fact. It can't be disputed, there are mountains of evidence that clearly cannot satiate your desire to despite the facts.
The article is not saying that building new infrastructure is pointless, but building a road that will primarily be used by single occupant vehicles is a very ineffective way of transporting people. The tireless champions of new highways that say people will never use transit as the build-form of the suburbs are designed around cars refuse to acknowledge that transit ridership has in fact grown in these car dependant suburbs.
 
The tireless champions of new highways that say people will never use transit as the build-form of the suburbs are designed around cars refuse to acknowledge that transit ridership has in fact grown in these car dependant suburbs.

I almost missed that the word 'grown' was a link... great article!
 
Why must someone cite experts for a principle (in this case induced demand) that is a proven fact. It can't be disputed, there are mountains of evidence that clearly cannot satiate your desire to despite the facts.
The article is not saying that building new infrastructure is pointless, but building a road that will primarily be used by single occupant vehicles is a very ineffective way of transporting people. The tireless champions of new highways that say people will never use transit as the build-form of the suburbs are designed around cars refuse to acknowledge that transit ridership has in fact grown in these car dependant suburbs.


It indeed has grown - the problem is that it's not growing fast enough to offset new car trips from growth ;)

I did the math before and in order for the GTA to offset all new auto trips generated by population growth over the next 30 years, annual transit ridership needs to grow by about 30% annually every year from now to 2051. Good luck!
 
It indeed has grown - the problem is that it's not growing fast enough to offset new car trips from growth ;)

I did the math before and in order for the GTA to offset all new auto trips generated by population growth over the next 30 years, annual transit ridership needs to grow by about 30% annually every year from now to 2051. Good luck!
I'm unsure why you think a 30% increase is unattainable in 30 years.
 
I'm unsure why you think a 30% increase is unattainable in 30 years.
not that little!


This report says that there will be about 310,000 more peak-hour trips in Peel in 2041 than in 2011, an increase of about 44%. To offset that with non-automotive modes, non-automotive options will have to increase by 200% over the same period from about 155,000 peak hour trips to 465,000 peak hour trips! Further, Peel Region, a very suburban municipality, would have to be posting automotive modal share rates similar to dense cities to the likes of Cologne Germany, Kuala Lumpur, and Athens.

The report also uses dated assumptions in terms of population growth, which has since been revised upwards. To offset new automotive trips, sustainable options would need to increase even faster annually to reflect the faster rate of growth.

It also ignores the fact that peak hour trips rely on sustainable modes at far higher rates than non-peak hour trips. Which means that you need even greater offsets for those trips.
 
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not that little!


This report says that there will be about 310,000 more peak-hour trips in Peel in 2041 than in 2011, an increase of about 44%. To offset that with non-automotive modes, non-automotive options will have to increase by 200% over the same period from about 155,000 peak hour trips to 465,000 peak hour trips! Further, Peel Region, a very suburban municipality, would have to be posting automotive modal share rates similar to dense cities to the likes of Cologne Germany, Kuala Lumpur, and Athens.

The report also uses dated assumptions in terms of population growth, which has since been revised upwards. To offset new automotive trips, sustainable options would need to increase even faster annually to reflect the faster rate of growth.

It also ignores the fact that peak hour trips rely on sustainable modes at far higher rates than non-peak hour trips. Which means that you need even greater offsets for those trips.
Growing by 30% vs an additional 30% in overall ridership are 2 very different things. I agree adding 30% to overall ridership is extremely difficult, and with that I agree with you.
 

There's a Christmas tree shortage in Ontario as demand for real trees soars

See link.

Wonder if there are trees available along the Highway 413 right-of-way? 😭



65994171.jpg
From link.
 

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