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Simple - the top figure (92% of pre-Covid) is DfT/TfL from the Strategic Road Network whereas the Southwark figures (reduction of 21,000 vehicles) are from local road monitoring.


I did write a longer reply explaining it far better but whatever restrictions are on this forum to prevent "non East Dulwich" matters from being discussed seems to prevent me posting it.

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Ex- not entirely correct, there's another twist and you, I think, highlight where the council has been trying to hide/mislead on what is actually going on.


"Traffic has been rising across Southwark since the end of the 2021 COVID-19 lockdown, and was at 92% of pre-COVID levels in November 2021 at count points in the north of the borough, and above pre-COVID levels on the TfL network near Dulwich" - Southwark Council Dashboard.


So from this we can ascertain that in the north of Southwark the traffic levels are lower than pre-Covid times - that's understandable and in line with expectations as travel/commuting habits change post-pandemic.


The council have also been claiming 21,000 fewer journeys in Dulwich but given what they are saying about TFL network traffic levels around Dulwich that doesn't make much sense - in fact it is completely contradictory.


But this where it gets interesting because there's always been the issue of "boundary roads" and whether the council counts those as part of the LTN impact area.


I very much believe that what we are seeing here is LTN displacement in action. That the supposed reduction in journeys "within Dulwich" are just being pushed from the LTN areas onto boundary roads - and those boundary roads are the ones monitored by TFL - A205, Lordship Lane, EDG, Croxted Road - in other words the main arterial routes around Dulwich. It wasn't felt in the early days after the pandemic because the general reduction in traffic wasn't being modelled by the council - it was all being spun as "good news" of lower traffic (they claimed because of the LTNs).


This was always the worry that as things started to return to normal the squeeze of the LTNs would be felt by the surrounding roads at a greatest rate. It's why we can now explain how, despite of claims traffic being greatly reduced across the whole borough after the pandemic there were still roads in Dulwich that were showing increases in traffic and that could only be because of displacement.


Look at the latest info on the council's dashboard (https://www.southwark.gov.uk/transport-and-roads/improving-our-streets/live-projects/streetspace/traffic-data-analysis) and look at weekday am peaks for the roads they monitor in Dulwich (which I suspect are the TFL monitored roads because they are key bus routes) - many of them are consistently higher than pre-Covid and that should be ringing alarm bells because we haven't seen a return to overall pre-pandemic traffic patterns in London yet (maybe we never will but the trend is alarming). And I bet the A205 is even worse. With each data set it demonstrates that these are the roads soaking up the displacement as traffic routes around the closures. Which was inevitable from day one and is certainly a long way from the success criteria set by the council for LTNs.


Interested to hear you thoughts.

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That sounds as though there has been a significant transfer of traffic from local roads to the SRN, which is what those in favour want to happen and which those against, and on main roads aren?t in favour of in circumstances where the outcome is to overwhelm the SRN roads?


Intuitively it feels as though there should be a combined figure covering local roads and TfL roads. But I?m not quite sure how that would work. Unless you can take a snapshot of ALL the traffic in the area at various set points in time and then compare with previous set points in time, surely any reductions / increases that you measure only show for certain that traffic at particular points has increased / decreased but can?t tell you what the overall reduction is, as traffic may have diverted from/ to non- measured routes? I?m not explaining very well, but for eg you can say a reduction of 21000 vehicles on certain routes (and even then could be some double counting I suspect as presumably one vehicle could disappear from say three counts depending on its route- or is that adjusted for?), but there?s no way of knowing whether the 21000 cars have popped up on other roads that aren?t being measured?

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Good to know that I?m not alone in identifying the potential for a ?redistribution? conclusion.


Given I?m in favour of road user pricing, ideally based on in-car technology, I?ll keep my fingers crossed that we can track actual car movements/journeys sooner rather than later, as the info gathered would be really useful for these discussions. (Lengthy discussions on privacy and the surveillance state to be had, no doubt)

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rahrahrah Wrote:

-------------------------------------------------------

> Don't know whether this has already been flagged

> somewhere on this thread. But this looks like a

> good local campaign, aimed at reducing the number

> of people driving to schools:

> https://sustainableschoolr.wixsite.com/sustainable

> schoolrun


That does look like the start of a good campaign, will have a further read. Not sure that allowing councils to be able to introduce CPZs more easily should really be a focus (unless it?s restricted to areas around schools there is potential for misuse of powers), I?d rather see more no stopping zones and school streets. If schools (state or private) want to have no catchment policies (which tbh I?m not in favour of) then they should have to contribute to the cost of an appropriate school transport solution. The primaries are certainly more of an issue than the secondaries, as the site suggests.

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legalalien Wrote:

-------------------------------------------------------

> That sounds as though there has been a significant

> transfer of traffic from local roads to the SRN,

> which is what those in favour want to happen and

> which those against, and on main roads aren?t in

> favour of in circumstances where the outcome is to

> overwhelm the SRN roads?

>

> Intuitively it feels as though there should be a

> combined figure covering local roads and TfL

> roads. But I?m not quite sure how that would work.

> Unless you can take a snapshot of ALL the traffic

> in the area at various set points in time and then

> compare with previous set points in time, surely

> any reductions / increases that you measure only

> show for certain that traffic at particular points

> has increased / decreased but can?t tell you what

> the overall reduction is, as traffic may have

> diverted from/ to non- measured routes? I?m not

> explaining very well, but for eg you can say a

> reduction of 21000 vehicles on certain routes (and

> even then could be some double counting I suspect

> as presumably one vehicle could disappear from say

> three counts depending on its route- or is that

> adjusted for?), but there?s no way of knowing

> whether the 21000 cars have popped up on other

> roads that aren?t being measured?



And we have to remember that the council's monitoring area originally only ran only as far as (and not including) Lordship Lane in the very early days of this programme. Additionally remember their initial monitoring efforts were only on the closed roads (remember the phantom monitoring strip killer) and they had to be forced to install strips on Lordship lane etc (which they subsequently moved to a more monitoring advantageous position towards Melford).


I very much suspect they knew all along what the impact was going to be and have done their utmost to try and spin the narrative their way.


Welcome back Rahx3.....are you goi.....nah I won't waste my time ;-) That initiative you link to is very good - the app is a great idea but not sure CPZs are necessary around every school, seems like a sledgehammer to crack a nut and no-one should be encouraging the council to install more CPZs - surely school streets would be a much better idea? If this was adopted you're pretty much saying you need CPZs on every street across Dulwich - else you just move the problem a couple of streets away.


I would love to know what the council are doing to tackle the school run problem - that site gives some sobering stats on the issue for the Dulwich area and the influx (during term-time) of thousands of pupils from beyond a 3 mile catchment area. Are the council even talking to schools about what they can do?

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Just heard Chris Boardman on Radio 5 talking about the new e-bike try-before-you-buy pilots in Manchester which is a really good idea but in the interview he said that a quarter of car journeys in the UK are under 1 mile - where is he getting that stat from? That's not correct is it?
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Successive ministers have talked about the need to replace short car journeys with active travel. You'd think that I could easily find a reference to this, but no. So there is a messaging issue both from the centre but also the masses who are either not getting the message or not listening. That's an observation, not a loaded comment.
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Across the Uk ...this is correct, but the mean average is a poor statistical method of looking at behaviour and is in isolation of local factors.


In rural areas there is very, very poor PT. Try living in Lincolnshire without a car! In Dulwich/ED there has been a very high amount of active travel locally for years - the issue here is schools really. I'm not sure the conversion rate of local car journeys to active travel will be high in DV/ED because so many of us already choose walking - why? Because except for those horrid congested hours in the morning, it's a lovely place to walk, just a shame that me, kids going to schools have to walk in a car fume fog..


E-bikes are a brilliant way to travel, but rural areas really need an investment is buses/ trains.


Maybe kids who travel actively or by PT pay lower fees than those chauffeured to school in the Porsche Cayenne or the BMW X7... in these times I find spending 100 grand on a car pretty disgusting, especially when parked illegally on EDG with the engine running..

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But there is also a resistance to not using your car, in parts of Britain outside of London. Not jus rural areas, where you could argue that public transport and active travel are limited, but urban areas too. I've family and friends across the country who are surprised when I talk about not doing short distances by car. Public transport is seen as poor peoples' transport, and some are happy to run and cycle for exercise, but not to go to the newsagents. Loss of local shops exacerbates things. Back to my last message about messaging.
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Mark Wrote:

-------------------------------------------------------

> I'm afraid it is:

>

> In 2020, 25% of trips were under 1 mile, and 71%

> under 5 miles.

> Source: National Travel Survey 2020

> https://www.gov.uk/government/statistics/national-

> travel-survey-2020/national-travel-survey-2020#:~:

> text=Journey%20lengths,-Chart%203%3A%20Mode&text=I

> n%202020%2C%2025%25%20of%20trips,and%2068%25%20und

> er%205%20miles.


But a trip is not a car journey. Look at the chart on the link you sent - it shows 81% of trips under a mile were walked. About 14% are cars/vans and I would love to know how they categorise the use of vans - how do they categorise a delivery van doing multiple stops for example?


14% is still too high but nowhere near the 25% he claimed and he claimed this for cars - it's very misleading and he should know better in his role.

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That's why I checked Boardman's claims as I just couldn't believe it was that high. I have relatives who live in the country and they drive a lot because there is no other option - for example their nearest supermarket is 12 miles away - they don't drive short distances because there is nothing to drive to - the shortest trip they do is to the village pub and that is always done on foot for obvious reasons!
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Context is all


"In 2020 there was a sharp decline in average miles (-33% to 4,334 miles), trips (-22% to 739 trips) and hours travelled (-27% to 269 hours) compared to 2019, all having the lowest on record during a year when the coronavirus (COVID-19) pandemic resulted in restrictions on people?s travel."

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Quite right too. There is very little excuse for owning a car or driving in London now.


heartblock Wrote:

-------------------------------------------------------

> My friends don't drive at all in London and don't

> own a car..I'm not sure they even have a licence..

> in fact I'm struggling to think of any of us

> driving in London.

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If I read this correctly it's that 25% of trips are less than a mile and around 14% of that 25% are cars / vans, so around 3.5% of trips are by cars travelling less than a mile (not a question of comparing 14% with 25%?). I actually find it surprising that only 25% of "trips" are less than a mile. I wonder what the definition of "trip" is and whether some "very short" trips haven't been counted as trips. Hard to know

Rockets Wrote:

-------------------------------------------------------

> Mark Wrote:

> --------------------------------------------------

> -----

> > I'm afraid it is:

> >

> > In 2020, 25% of trips were under 1 mile, and

> 71%

> > under 5 miles.

> > Source: National Travel Survey 2020

> >

> https://www.gov.uk/government/statistics/national-

>

> >

> travel-survey-2020/national-travel-survey-2020#:~:

>

> >

> text=Journey%20lengths,-Chart%203%3A%20Mode&text=I

>

> >

> n%202020%2C%2025%25%20of%20trips,and%2068%25%20und

>

> > er%205%20miles.

>

> But a trip is not a car journey. Look at the chart

> on the link you sent - it shows 81% of trips under

> a mile were walked. About 14% are cars/vans and I

> would love to know how they categorise the use of

> vans - how do they categorise a delivery van doing

> multiple stops for example?

>

> 14% is still too high but nowhere near the 25% he

> claimed and he claimed this for cars - it's very

> misleading and he should know better in his role.

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I wonder what the definition of "trip" is and whether some "very short" trips haven't been counted as trips. Hard to know


Depends on the model (if you're modelling actual journeys). A journey is the same as a trip.

It does also depend on the context as well. Equally, if you're analysing (say) mobile phone data to determine movements, it does fall down a bit on very short trips. If you do a 500m journey in a car in stop start traffic, it will potentially record you as walking.


You can break trips down in to stages which is useful if you're doing multi-modal stuff. If a traveller drives to the station and then takes a train from there, some models will count it as one trip with two stages, other models might record it as two separate trips. It does depend a lot on what you want the model to actually show.


Basic example - a parent drives a child to school, drops them off and then returns home. You can record that as two entirely separate trips:

Home > School (2 occupants)

School > Home (1 occupant)


or you could record it as one car trip starting and finishing at Home. If you want to work out how many parents are driving a child to school then returning home vs how many parents are dropping their child off then continuing on to their own workplace for example, it's a critical distinction to make. The Home > School > Home trips are easier to replace by A/T - sending the kid off to cycle to school on some nice safe cycle infrastructure.

The Home > School > Work one is less easy to replace in that fashion.


There isn't really a right way or wrong way to record this so long as you're clear about what sort of travel demand you're looking at.


it shows 81% of trips under a mile were walked


Walking itself is rarely modelled as a "trip". It's quite tricky to do mostly because it's difficult to determine what counts as a walking trip.

If you walk up LL, stopping at 5 shops en route, does that count as 5 trips between shops or one trip including shops? That example by the way is critical for stuff like footfall predictions, it's not just unnecessary pedantry.


The basic premise of what Chris Boardman was saying is entirely correct though. There are far far too many very short journeys done by car. Again, part of the point of LTNs is to discourage that. If it's a direct 500m trip from Home to (say) Dulwich Hamlet but now the LTN has forced you to go to Townley, EDG, Village then it discourages that car trip in favour of walking. And yes, I have seen people drive 500m to school, the shops etc.

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Oh my??this Manatee just won?t sink.


Admin - keep the strength, you do a fantastic job.


Ex- but by the same bar do they count a delivery round as a single journey or many short trips? Chris Boardman was wrong to say 25% of journeys in cars are under 1 mile but I suspect he knew what he was doing b6 saying it. In his position he should have known better. It?s deliberately misleading like much of the data we see from the council and others in support of LTNs. It was the reason I was asking for someone from the pro side to decipher the council?s and TFLs contradictory monitoring data. LTNs clearly create huge displacement and not traffic evaporation and the data is really starting to amplify that as the benefit from pandemic traffic reductions are lessened.

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I think that we have reached an understanding from both sides, that the issue is too much traffic, and the main reason being that many drivers are not prepared to change their habits, eg cutting out unnecessary journeys, lift sharing or switching to other modes. Where we disagree is how this is best achieved, in particular the role of LTNs and if and where they should be applied. I doubt whether there is much more we can debate so perhaps time for the thread to end. Not that I have the authority to do so! Sweet dreams all.
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It would be interesting research to find out why people might drive a short journey rather then walk/cycle/catch a bus. In medicine we usually try to understand why something is happening before flinging 'cures' at the problem. Maybe Southwark could fund that research? As I say... my friends scattered around South, East and North London do not drive in London, but I know a few people in ED who drive short journeys - one to JAGs sports centre (prob a 20 min walk) and one to Sainsburys (I personally like to walk through the back via Greendale). I would like to know why they make that choice.


I think the thread should stay, sadly EDF may go anyway :( and we may have to put up with the Troll - who by the way I do not think is in anyway representative of any pro-LTN campaigners or supporters - and maybe we carry on thinking about where we go from here to actually improve the environment and lives of all residents in this area.

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Waseley, absolutely no requirement for you to continue reading or participating in this thread, so curious why you feel the need to close it? I suspect it will continue for some time.



Waseley Wrote:

-------------------------------------------------------

> I think that we have reached an understanding from

> both sides, that the issue is too much traffic,

> and the main reason being that many drivers are

> not prepared to change their habits, eg cutting

> out unnecessary journeys, lift sharing or

> switching to other modes. Where we disagree is how

> this is best achieved, in particular the role of

> LTNs and if and where they should be applied. I

> doubt whether there is much more we can debate so

> perhaps time for the thread to end. Not that I

> have the authority to do so! Sweet dreams all.

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