London saw a surprising benefit to ultra-low emissions zone: More active kids

It cuts across every demographic. Under 25k household income - a good 40-50% of households have a car. Housing estates - tons of cars. Well off - almost everyone.

https://content.tfl.gov.uk/technical-note-12-how-many-cars-a...

It mostly comes down to whether someone has a need (e.g. has children, fairly mobile in their job, has family outside of town, enjoys going on road trips etc) and actually wants to pay for it rather than anything else.

In addition to that, a bunch of stuff happened basically at the same time. We got ULEZ, we got a ton of low traffic neighbourhoods (e.g. streets where cars are not allowed at certain times of day regardless of emissions), we had COVID meaning that habits and demographics changed, we had Brexit which probably had some minor effect, etc. All of that happened within about 5 years and I don't think you can isolate any of them.

I don't really find most discussions about it interesting as a result of all of the above - it usually just ends up with someone trying to find evidence for their pre-existing position rather than anything that feels actually scientific, unfortunately.

I would think it probably greatly reduced the amount of traffic in that area, which all around just makes for a more pleasant experience being a pedestrian, biker, or scooterer.

Regardless, I think this is awesome and wish it could be tried in the United States. Kids being able to be independent and active is essential to their happiness and development.

They can play football or baseball or soccer or frisbee or tag. Doesn't matter. What matters is that you give them the room and let them do their own thing. Not only would this help them be more active, but it'd help them socialize a great deal more than they normally do.

I'm not against EV at all, even though it is overhyped on the one side and demonized on the other. What bothers me is the hypocrisy in messaging. You can not pretend going full EV in 10 years and not be on a never befote seen giant grid replacement right now.

So what is it? Are you going to make car ownership in the city a 1% privilege? Will not much change but will everybody have to pay the exemption fee (oh yes, that exists)?

Both can be an acceptable position, just don't pretend.

I can tell from experience there is a big difference in the air. In that area it smelled like exhaust and smog, while the center had no such thing.

When I reflect on it, I feel that the less affluent areas have been left out to dry / rot in the exhaust. While the upper class city center is now pristine.

* France requires postal pre-registration (they send you a sticker)

* in Italy you have to check with each municipality, who at best show you a low-res drawing of the LEZ

* (Italy:) Google Maps doesn't know about Low Emission Zones, so it happily sends you through

* (Italy, too:) There seem to be very little pedestrian zones. You can drive everywhere, through the Low Traffic Zone might not permit you through. For Google Maps, you can drive everywhere… but you'll end up getting a fine.

I'd like to see way more LEZ, but in practice, it is such a mess unfortunately…

There's More To Dutch Roads Than You Think - https://www.youtube.com/watch?v=b4ya3V-s4I0

In New Zealand I saw large vehicles like utes and defenders doing actual jobs on the terrain that they were built for. The only SUVs that I really saw were out in the wops where they wanted a dual purpose vehicle or the time I saw Saudis laughably trying to drive a 1.5 lane width full-size hummer in central Auckland.

Whereas in London, YoY since I moved here I only see more SUVs clogging the narrow roads. No pop-up headlights on a sports car for me, because they'd endanger pedestrians! But a 2 tonne defender with a brick wall of a front is perfectly fine! Not only that but it seems like >20-30% of the vehicles on the road are SUVs and are usually driven by a single occupant!

It's honestly think it's a sign of the times and of the direction our futures are going. The dystopian novels were real.

I think this article is mixing up correlation vs. causation.

Funny sidenote: since the ULEZ now covers Heathrow, what's the charge for an Airbus A380?

And think of all the accidents avoided from these guys not driving to school!

The study is here: https://ijbnpa.biomedcentral.com/articles/10.1186/s12966-024...

The data was collected during the 2018/2019 academic year and then during the 2019/2020 academic year (but before the Covid school closures).

First, some context: -The original ULEZ, which the referenced study looked at covers central London and should not be confused with the much larger recently expanded ULEZ which covers the whole city. Nor should it be confused with the much smaller congestion charging zone or the larger and older Low Emission Zone which covers freight vehicles. -The ULEZ rules are designed around penalising the driving of the oldest and most polluting vehicles only. In 2019 this was 80% of cars, the expanded ULEZ has overall vehicle compliance of 95%+.

As as result of the second point, it would not be expected that it would have a substantial effect on the number of vehicle journeys since 80% of passenger cars in the zone were already compliant anyway, therefore any effect at all is actually surprising. The paper notes a drop of 9% in total vehicle counts.

"Four in 10 London children stopped driving and started walking to school a year after the city's clean air zone went into effect."

This little quote heads the article. It seems like quite a result, right?

It isn't.

Let's look at the baselines here, something which immediately anyone who lives in London would be suspicious about because like me their first question would be: "who was driving their kids to school in central London in 2019? Are there enough for there to be four in ten at baseline to switch?". It turns out not many people do, and no.

Let's look at table 2 from the paper: (there were about 1000 kids in both the Luton and London samples) At baseline, 856 kids in London travelled using active modes and 105 using inactive modes In Luton that was 599 and 364 respectively

So first, we can say that "four in ten children" has to be interpreted pretty carefully here since 85% of kids were already walking to school (note that if they just took the bus the whole way this also counted as walking).

At most, we must be talking about changes to the minority of kids who weren't using active travel before, in other words maybe it's that "Four in 10 London children (of the minority who were being driven) started walking to school.

But, if we look at the changes, that doesn't quite stack up either.

In London: 47 kids switched from active to inactive (all measured based on travel "today" and in many cases there will be variation in modes across days) 44 switched from inactive to active 61 inactive/inactive 809 active/active

In Luton:

124 active/inactive 74 inactive/active 290 inactive/inactive 475 active/active

It doesn't look like, ignoring the Luton control for the moment, there was any modal shift at all for London!

Luton has proportionally shifted away from active transport and only in relative terms to the control has there been a modal shift.

This is already a much less positive message. "Kids in general less likely to walk to school, except in London where (potentially due to a low emissions zone) their behaviour didn't change." Where's my four in 10 gone?

The "four in 10" comes from the 44 kids who were inactive in the first sample but active in the second (out of 105 total inactive in first sample). Of course that is a much larger % of children from that group who switched in that direction than the 47 who switched the other way from much larger number of first sample actives. If your transition probabilities from A to B are much higher than B to A, but B is much larger group, you can end up in this situation here where you have impressive sounding % changes which nonetheless mean nothing and don't change the population behaviour at all.

It's a very fine thing, no doubt, to run multilevel binomial logistic regression models on data and come up with statistically significant odds ratios but I don't think these results remotely justify the news article headline and subhead.

Am I missing something here? Obviously if you apply sin taxes to driving then people who can't afford to pay them are going to be forced to drive less. I bet there would be plenty of "surprising benefits" if we banned all road vehicles and forced people to get around on foot and push bike too...

This article seems to be both making an extremely obvious observation (that the introduction of ULEZ is forcing poor families to get around the city in alternative ways) and missing the fact that such decisions come with both positives and negatives which need to be weighed up.

If we simply want to implement policies to benefit children's health then we'd probably be better off banning junk food. But we don't do that because we understand that there are trade-offs.

ULEZ has been a disaster for many working families and it's highly unpopular for a reason. If you're poor and don't live in the inner city, or if you don't have a nice middle-class office job and need your car/van for work then ULEZ makes you poorer and your life more difficult.