LTN Discussion

[Rockets]

Earls, Earl, Earl.

All you have done is posted a passage from the report that validates what we were saying that traffic decreased inside the LTNs but increased outside of it...remember Cllr McAsh's statement that if everyone did not benefit from a reduction in traffic then they should be considered a failure?

 

Let's look at what you posted...

...Mean falls in motor traffic on internal roads are around ten times greater than mean rises in motor traffic on boundary roads, adjusting for background trends... the results indicate that motor traffic has been reduced, and only a small proportion re-routed to boundary roads. This is suggested by the mean increase of 82 vehicles per day on each boundary road being much lower than the mean reduction of 815 vehicles on each internal road."

 

....what it says is the increase in traffic on the boundary road traffic is less than the decrease of traffic on the roads within the LTNs so somehow justifying LTNs as a success because that traffic from within the LTNs is not using the boundary roads and therefore it has magically "evaporated". All well and good until you actually analyse the data these reports are taken from and then you realise that the claims of "evaporation" are utter nonsense.

 

This research uses the council's own monitoring data (the same data Aldred and Co) used for their reports which came to the same, (knowingly), flawed conclusions. 

 

Let's look at East Dulwich for an example (and there are more examples from every council who provided monitoring data) for some of the reasons why this data is seriously flawed and incomplete:

• The only "boundary road" Southwark monitored east of the DV LTNs was Lordship Lane.
  • This makes the ludicrous assumption that displaced traffic would only use Lordship Lane to avoid the LTNs - anyone who lives locally knows this is not the case.
  • The council started to monitor Underhill but never published the results but talk to anyone who lives near there and they will tell you the traffic increased significantly post LTNs, likewise there was no monitoring on East Dulwich Road, Barry Road or Crystal Palace Road - in fact absolutely nothing east of Lordship Lane and nothing south of the interventions on Dulwich Common (although I think their excuse on Dulwich Common was this is a TFL road)
• On the boundary roads they did monitor Southwark also used the limitations of pneumatic monitoring under 10km'h to their advantage 
  • They deliberately placed the monitoring strips close to junctions to ensure slow moving traffic was rolling over them
  • In fact, the Lordship Lane South monitoring strip started its monitoring life near the bus stop just up from Court Lane  (going towards Goose Green near the crossing refuge) but then, mysteriously, moved to just before the junction of Melford Road (between that and the entrance to Byron Court) where the road narrows and traffic crawls (actually further towards the Grove Tavern from where it is indicated on the council's own map below). 

 

So, the research is very misleading and, I suspect, knowingly so, so that supporters will wave it around showing that the LTNs have been a "great success" because they know full-well that those who support them will lean heavily on their own confirmation-bias and not actually bother to look at the detail or properly read and understand what the reports says or detail behind it.

 

 

[CPR Dave]

1 hour ago, Earl Aelfheah said:

I suggest you read it (I mean if you're genuinely interested in the facts and not just confirming your bias). It's quite nuanced and the narrative is interesting. But overall LTNs have reduced traffic

I've read it thanks and added the bit you left out - traffic down inside LTNs, traffic up on boundary roads.

[Rockets]

On 25/11/2023 at 10:49, DulvilleRes said:

I am a huge supporter of local debate and democracy, and on that basis, I do have an issue with One Dulwich's lack of transparency.

Sorry still laughing at this!

 

On 25/11/2023 at 10:49, DulvilleRes said:

I would ask One Dulwich myself some of these questions, but I saw what happened to local people who were in favour of LTN's who put their heads up.

Oh my goodness, really! Here's their email address, drop them a line, ask them the question: https://www.onedulwich.uk/contact. I bet you have more chance of them replying that anyone questioning the council about the LTN policy ever did!

 

On 25/11/2023 at 10:49, DulvilleRes said:

As far as I am aware, the likes of Clean Air Dulwich have never posted their press releases directly on this forum

 

One Dulwich aren't posting them. I have posted most of them and I have nothing to do with One Dulwich - I have never spoken to any of the people that run it and I get their updates because I registered my support when they first started their campaign and anyone on that list gets emailed them. And the fact the posting of these updates seems so upset those who claim to "support local debate and democracy" suggests to me that I am absolutely doing the right thing! 😉 

 

Bottom-line is that there are some who will do anything to try and quell the dissenting voices - I am so glad One Dulwich are doing what they are doing because they are providing a counter-balance to the council/pro-LTN lobby narrative. And just think, if they hadn't have been doing what they were doing to mobilise the support against the measures the council would have had free reign to roll out whatever they wanted. This is very much the democratic process in action...One Dulwich is acting as a people's voice when the council refused to hear what people were saying.

[first mate]

DulvilleRes, please do email and ask One Dulwich and you can share their reply on here.

[heartblock]

Rachel Aldred’s latest report  - Changes in motor traffic in London’s Low Traffic Neighbourhoods and boundary roads - a meta -analysis

“There are known issues with data quality. Usually, reports used Automatic Traffic Counters (ATCs) to monitor traffic, in most cases ‘tubes’ across the road”  “These are imperfect. Parked or very slow-moving motor traffic may affect results"

“We have not accessed raw data directly from counters, as this would not be feasible for so many count points, schemes, and boroughs"

“it is important that boundary roads are not forgotten. They do experience often substantial traffic burdens, and just over half the boundary roads in this study saw increases over the monitoring periods"

"There are limitations to what one can conclude from average daily motor traffic counts. For instance, changes in motor traffic volumes do not correlate linearly with congestion, which is time-specific, nor do they directly map onto air pollution where speed and other variables play an important role"

 

[DulvilleRes]

Rockets – it is a great loss to One Dulwich that you haven't spoken to the people behind the lobby group, as you are so clearly a trendsetter when it comes to the LTN debate. You were posting about the Public Accounts committee/ National Travel Survey report a full month before One Dulwich’s latest missive highlighting it. I’m just puzzled, that as someone concerned with local democracy, that you have no knowledge or curiosity as to who might be behind the work you are promoting, especially in the light of the critical attention you pay to the credentials of anyone who might put forward a pro LTN point of view. I genuinely don’t understand this disparity of approach. 

The Daily Mail has been fairly regularly covering the Dulwich LTN issues, and recently describes one of the former local Conservative councillor candidates as a ‘local campaigner’. This would certainly correspond with pattern of LTN - related questions that the former Conservative councillors have been formally asking at a town hall level. Those questions are closely aligned to One Dulwich concerns. It could all of course be entirely co incidental, but is it possible that the ‘campaign’ referred to by the Mail is One Dulwich? 

As an aside, One Dulwich seem to have the ear of the Daily Mail. I find it quite surprising that hyper local stories seem to find their way into the paper quite regularly, especially in light of the fact that journalism, even at the comparatively wealthy Mail, is very much on the back foot these days. A lot of the news cycle is actually driven by PR culture, of interest groups reaching out to the papers. Again, there is no way of knowing how the Mail picks up its stories, but the question could be asked - is there some kind of connection between the two? 
 

[first mate]

But Dul, you are the poster that so wants to know who is behind One Dulwich, so why don't you email and ask them? Seriously, get an anonymised email, contact them and post what they reply.

Or is this just a rather sorry and disingenuous attempt to undermine Rockets's credibility...implying they must be running some sort of Tory PR op for One Dulwich also involving the Mail? Seems you follow stories in the Mail quite closely then?

It has become a bit of regular 'thing' for pro-Council- traffic-measures posters to insinuate anyone against or even questioning must be a Tory, as well as a Mail toting petrol-head. It's all a bit scraping the barrel when there is nothing left to defend the appalling mismanagement and undemocratic imposition of a raft of traffic measures by this council.

[Rockets]

DuvilleRes - I am happy to promote them by posting their missives on here because I agree with the message they are delivering. It's precisely the fact that I am concerned about local democracy that I am keen to promote their messages - because the council was killing the local democratic process with their actions around Healthy Streets, LTNs and, more latterly, CPZs.

 

As a Dulwich Village resident (we presume) I am sure you are benefitting from the closure (like I am) so, of course, you are reluctant to see voices suggesting they are anything other than wonderful. Look we all know what you are trying to do - tarring OneDulwich as a Tory-led lobby group (it must be really annoying that you can't find a link to some fascist, taxi-driving, covid-denying flat-earther as then you'd have the full-house! ;-)). 

 

You know there are a couple of Daily Mail journalists living in Dulwich right - one of them recently wrote about their cycle to and from their office and another "grassed" on Meat Liquor from their flat window during lockdown? So maybe, all they are doing is, like Peter Walker, using their local knowledge to create stories - although Peter did seem to benefit a lot from all of the Rachel Aldred, ahem, exclusives on LTNs.

Amazing, isn't it, how Aldred's statement in her latest report cast huge amounts of shade on the validity of all the previous "exclusives" yet the Guardian didn't pick up on that....

[Peckham Park]

LTNs and other traffic reduction schemes are supported by American billionaires providing grants to all forms of eco lobby groups. Southwark is part of a national lobby group UK100. Don’t see Dulres asking where they get their money from? https://www.uk100.org/

[first mate]

Yes and they also obliquely prop up big US tech companies like Lime by allowing them to occupy and monetise our public spaces.

[first mate]

Having just posted on another thread about proposals to extend the duration of the Gala Festival in Peckham Park, I wonder how those in favour of LTNs and other alleged pollution- saving and greening-of-the-environment moves, square that 'mission' with what this council are trying to do by extending privatisation of our park? Is there not an inherent contradiction in all this?

[Earl Aelfheah]

On 27/11/2023 at 12:20, CPR Dave said:

I've read it thanks and added the bit you left out - traffic down inside LTNs, traffic up on boundary roads.

I doubt it. Apparently you didn't even read my post properly. The quote is clear that there has been a small increase, on average on some roads, and bigger drops on others. The net outcome - an overall drop in traffic:

"...Mean falls in motor traffic on internal roads are around ten times greater than mean rises in motor traffic on boundary roads, adjusting for background trends... the results indicate that motor traffic has been reduced, and only a small proportion re-routed to boundary roads. This is suggested by the mean increase of 82 vehicles per day on each boundary road being much lower than the mean reduction of 815 vehicles on each internal road."

On 01/12/2023 at 17:13, scrawford said:

LTNs and other traffic reduction schemes are supported by American billionaires providing grants to all forms of eco lobby groups. Southwark is part of a national lobby group UK100. Don’t see Dulres asking where they get their money from? https://www.uk100.org/

You can always read the 'about' section on their website. There is no great conspiracy. 

Edited December 4, 2023 by Earl Aelfheah

[Rockets]

1 hour ago, Earl Aelfheah said:

The net outcome - an overall drop in traffic:

Only if you are monitoring every road which could be considered a boundary road...which they were not. Nor did they factor in that much traffic is not being recorded because it was travelling at under 10km/h at the monitoring points on said boundary roads....

....but you know, don't let the truth get in the way of a "good story"! 😉

[sally buying]

I have noticed in "Bellenden Village" area the black monitoring strips are again running across the roads.

Is Southwark planning more information gathering now we are approaching the quiet christmas period to implement new schemes no body wants.

Always appears to happen during many holiday periods.

Perhaps they might like to monitor how many older people have to wait standing for the P13 instead of putting in the large amount of cycle stands for the young and able bodied put in some seating

 

 

 

 

 

 

Edited December 4, 2023 by sally buying

[Penguin68]

5 hours ago, Earl Aelfheah said:

The net outcome - an overall drop in traffic:

As even the 'experts' admit that the measurent system of traffic was flawed, being positioned such that slow moving traffic didn't register, and we know that proper 'before' measures weren't made across all the relevant routes this '"conclusion' is fatally flawed. 

[Earl Aelfheah]

We have a lot of data gathered from across London and a number of different schemes. Of course you can pick out imperfections and question individual data points, or interventions. But it's difficult to ignore the macro picture imo. Unless you are absolutely determined to confirm your preconceptions.

Edited December 6, 2023 by Earl Aelfheah

[Spartacus]

2 hours ago, Earl Aelfheah said:

We have a lot of data gathered from across London and a number of different schemes. 

Who exactly are "We" in your reference Earl ? 

Are you part of a shadowy pro organisation like Dulvilleres tries to paint one dulwich as 😅

Remember what is key here is local data for our local scheme.

[Earl Aelfheah]

Yes, I'm part of a shadowy organisation

[Rockets]

On 06/12/2023 at 01:20, Earl Aelfheah said:

We have a lot of data gathered from across London and a number of different schemes. Of course you can pick out imperfections and question individual data points, or interventions.

The majority of which was collated via pneumatic tubes which has since been found to have a major flaw - incorrect readings when used in slow moving traffic. 

Edited December 7, 2023 by Rockets

[Earl Aelfheah]

2 hours ago, Rockets said:

The majority of which was collated via pneumatic tubes which has since been found to have a major flaw - incorrect readings when used in slow moving traffic. 

This is one of those often repeated, but roundly debunked talking points on 'anti-LTN Twitter'.

There are, inevitably some drawbacks involved in tube counters (as there are for all monitoring methods), but they are generally accepted as being pretty accurate. There is a reason why they are the preferred way of monitoring traffic flows. For instance, a study by McGowen and Sanderson (who described themselves as ‘suspicious’ of pneumatic tube data) found that when using short counting periods (e.g. 15 minutes), error rates were much higher than manufacturer claims of around 1%. Errors would sometimes involve over- and sometimes under-counting. However, these errors are cancelled out over longer periods such that ‘for daily counts, the road tubes have small error rates consistent with those reported by the vendors.’. There can be issues with parked cars (parked on the tubes), which is why they often don't extend to the curb.

The monitoring data available however, uses daily averages based on longer counting periods. 

There has also been claims that they can't count vehicles which are travelling less than 10mph. This isn't true. You can set a minimum speed default, as well as defaults for the class of vehicle you want to count etc. It all depends on what you're measuring and happens at the software level. In Enfield, there was and error made because they forgot to reset the default speed minimum (which was set to 10mph). This was spotted and the data re-analysed, but of course, it was used by those looking to undermine any and all data on the impacts of LTNs (a reaction which itself is instructive). This has now become a 'fact' amongst those stuck in the 'war on cars' twitter rabbit hole.

No traffic count data can be 100% accurate and of course that is not the bar. Pneumatic tubes are thought to be around 99% accurate, so the data is generally reliable and the sample big enough to give an accurate picture of what has happened to traffic flows. The peer review process ensures that the data will be poured over, the methods of collection and analysis interrogated and critiqued. It is not equivalent to people on Twitter and a few right wing opinion pieces desperately looking for ways to sow doubt in data and research conclusions they just don't 'like'.

Edited December 7, 2023 by Earl Aelfheah

[Rockets]

On 27/11/2023 at 23:12, heartblock said:

Rachel Aldred’s latest report  - Changes in motor traffic in London’s Low Traffic Neighbourhoods and boundary roads - a meta -analysis

“There are known issues with data quality. Usually, reports used Automatic Traffic Counters (ATCs) to monitor traffic, in most cases ‘tubes’ across the road”  “These are imperfect. Parked or very slow-moving motor traffic may affect results"

Earl, sometimes the answers you are looking for are right in front of your eyes.

 

The manufacturers advise to not place the pneumatic counters close to junctions or areas of slow moving traffic....which is exactly where councils monitoring for LTNs did place them.....I refer you to Melford Road......

[Earl Aelfheah]

No method is perfect. But they're considered to be around 99% accurate when using daily averages.

The more interesting question to me is, why you're desperately looking for reasons to discount all and any objective monitoring data (because there is no 100% accurate way of monitoring traffic flows)? I mean I can guess, but interested in your self reflections. 

Edited December 7, 2023 by Earl Aelfheah

[Rockets]

Because from day one of LTN's the data monitoring, collection and analysis has been (in my mind deliberately) flawed to give inaccurate data to try to convince people that the measures are effective and delivering against their stated objectives.

 

But can you claim Melford Road is 99% accurate when for huge parts of the day it is under the very condition that makes the monitoring inaccurate...and why did that monitoring strip get moved from nearer Court Lane...do you want to take a guess? 😉

Edited December 7, 2023 by Rockets

[Earl Aelfheah]

Oh I see. It's a conspiracy, involving multiple independent consultants, local authorities, and academics.

[heartblock]

ATCs do not count accurately in slow moving traffic.

Traffic diverted to boundary roads causes slow moving traffic.

ATCs have been used on boundary roads to measure traffic to 'prove' that there is 'no increase' in traffic compared to traffic measured by actual counts (not ATCs) before LTNs in place.

So - I agree with Prof Aldred that ' reports used Automatic Traffic Counters (ATCs) to monitor traffic, in most cases ‘tubes’ across the road”  “These are imperfect. Parked or very slow-moving motor traffic may affect results'

Southwark Council used these before and after 'counts' to claim that small traffic increases on boundary roads were not significant and would soon decrease as a result of increased use of cycling and walking for short local journeys.

East Dulwich already had one of the highest percentages of walking as a local transport activity pre-LTNs and the majority of car travel in ED is due to long journeys/ school runs from outside the area for private schools/ commercial traffic.

So..not a conspiracy - but certainly incompetent, flawed and lacking scrutiny throughout.