FOI responses or research on braking and turning around LTNs and School Streets

[Rockets]

1 hour ago, Earl Aelfheah said:

There is air quality monitoring data freely available. I've posted it above. Pollution has not increased on any of the monitored roads.

On the backdrop of pollution falling across all roads (thanks to Ulez according to Sadiq) - what @Earl Aelfheah cannot tell us is whether the drop on some of the congested roads impacted by the LTNs is better or worse than roads not impacted by the LTNs.

What the data they are sharing doesn't tell you is if the increased congestion caused by displacement from the LTNs is increasing pollution on those roads. 

This is why the "12% area-wide drop in traffic" (whether you believe the 12% is accurate or not) is a misleading measure as if those cars are sitting in more congestion then pollution will be higher than if they are not. And everyone knows there has been more congestion on many of the displacement routes around the LTNs.

[Earl Aelfheah]

5 hours ago, Rockets said:

In 2019 it was a problem they acknowledged but by 2021 they either found a miracle cure or just didn't do the monitoring to avoid having to do any further acknowledgments

In 2019 there was no LTN, and yes, there was a problem with air quality. By 2021 they had introduced an LTN. That was the intervention (I wouldn't call it a 'miracle cure' but you can if you want) that they 'found'. They predicted that it would lead to a drop in air pollution, based on modelling. They have monitored air quality consistently since and it has improved across the area.

Edited 8 hours ago by Earl Aelfheah

[Rockets]

5 minutes ago, Earl Aelfheah said:

In 2019 there was no LTN, and yes, there was a problem with air quality.

Which was made worse by their intervention to improve active travel and air quality. Surely you must agree with that at least?

6 minutes ago, Earl Aelfheah said:

They predicted that it would lead to a drop in air pollution, based on modelling. They have monitored air quality consistently since and it has improved across the area.

But you still have nothing that links the LTN to the improvement in air quality - all you have is the council "modelling" that predicted a reduction in pollution? Do you have a link to this modelling? Was the modelling addressing roads within or outside the LTN?

You're clearly trying to weave your way out of this so let's do this one question at a time:

• Do you agree that congestion got worse on boundary roads like DV, Croxted, Lordship Lane at the junction of the Grove Tavern and Underhill, for example, when the LTNs went in?

[Earl Aelfheah]

1 hour ago, Rockets said:

But you still have nothing that links the LTN to the improvement in air quality - all you have is the council "modelling" that predicted a reduction in pollution?

Again (sigh) - there are vehicle counts that took place before the LTN was implemented and for a year afterward. It showed a general reduction in traffic across the wider area.

An independent consultancy were commissioned in advance of the LTN implementation to model the likely impacts on air quality before the changes. They concluded a likely drop in air pollution.

There is several years worth of air quality monitoring data from across Dulwich, all showing that pollution has fallen since the LTN was introduced.

All of this data strongly links the LTN to a reduction in pollution (that's not to say it's the only thing impacting pollution as I have already said).

The evidence 'supporting' your claim that pollution has increased involves a sentence about air quality in 2019, before the LTN was introduced, whilst ignoring the above. In other words, you offer no evidence.... It's almost as though you're entirely predictable

On 09/02/2026 at 16:13, Earl Aelfheah said:

Of course, Rockets will be here to tell you again (with no evidence at all) that pollution has increased. It hasn't.

Edited 7 hours ago by Earl Aelfheah

[Rockets]

18 minutes ago, Earl Aelfheah said:

Again (sigh) - there are vehicle counts that took place before the LTN was implemented and for a year afterward. It showed a general reduction in traffic across the wider area.

@Earl Aelfheah oh my.....come on, are you just playing silly for effect? Vehicle counts are utterly meaningless if those counted vehicles are spending time in congestion.

28 minutes ago, Earl Aelfheah said:

An independent consultancy were commissioned in advance of the LTN implementation to model the likely impacts on air quality before the changes. They concluded a likely drop in air pollution.

Which report is this - is this the 2018 Traffic Management Study? Do you have a copy?

29 minutes ago, Earl Aelfheah said:

There is several years worth of air quality monitoring data from across Dulwich, all showing that pollution has fallen since the LTN was introduced.

But air quality has been improving everywhere hasn't it?

29 minutes ago, Earl Aelfheah said:

All of this data strongly links the LTN to a reduction in pollution (that's not to say it's the only thing impacting pollution as I have already said).

Strongly links.....according to whom - you?

30 minutes ago, Earl Aelfheah said:

The evidence 'supporting' your claim that pollution has increased involves a sentence about air quality in 2019, before the LTN was introduced, whilst ignoring the above. In other words, you offer no evidence.... It's almost as though you're entirely predictable

There is a darn-sight more substantial local evidence of congestion than there is any evidence that the LTNs have had a positive contribution to pollution levels.

Are you avoiding my question on whether you agree whether there was increased congestion on LTN boundary roads (Croxted, Lordship Lane, Underhill, Dulwich Village) post LTN.

Yes or No?

[malumbu]

12 hours ago, first mate said:

If you have cars moving more slowly down a street, bumper to bumper and often idling, you are suggesting pollution will be reduced in the air on that road?

1. Traffic congestion is nothing new in London

2. Poor driving standards make a significant contribution to poor air quality, the vast majority of drivers cannot drive smoothly in traffic calmed area, accelerating/braking (wasting fuel as well, and increasing wear and tear).  And similarly drive smoothly on urban roads.

Ironic that that there is a call for speedbumps on Ryedale.

Of course that is because most drivers don't obey speed limits on urban roads.  Irresponsible.

What do you reckon?

[first mate]

4 hours ago, Rockets said:

There is a darn-sight more substantial local evidence of congestion than there is any evidence that the LTNs have had a positive contribution to pollution levels.

Are you avoiding my question on whether you agree whether there was increased congestion on LTN boundary roads (Croxted, Lordship Lane, Underhill, Dulwich Village) post LTN.

Yes or No?

I am also waiting for the response.