CityCyclingEdinburgh Forum » Infrastructure

The scandal of the 30mph buses

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  1. SRD
    Moderator

    There are definitely issues regarding arctic habitats that we need to worry about, but polar bears get way too easy a ride (according to a friend of mine who used to work for the Env dept in the Canadian North).

    Posted 12 years ago #
  2. splitshift
    Member

    buses, polar bears ....surely if some one could come up with say a ...tram system for the city, then all the problems would be dealt with at one goooo.......mmmmmmmm I see trouble ahead ..

    Posted 12 years ago #
  3. chdot
    Admin

    "but polar bears get way too easy a ride"

    You mean it's all their fault??

    Posted 12 years ago #
  4. Ahem...


    EricBarry by blackpuddinonnabike, on Flickr

    Posted 12 years ago #
  5. kaputnik
    Moderator

    Based on LB timetable.

    The number 5 bus runs between Morningside Station and Salisbury Place, a distance of 2,800m.

    At peak times it takes 13 minutes.
    Off peak it drops to a best time of 9 in the early morning nefore 730AM and after 630PM.

    That makes an average speed of 8.1mph at peak times and 11.7mph off peak, basically through the 30mph East-West corridor. Of course some of that will be pick up/ set down times. But it doesn't seem an insurmountable challenge to get that sort of average with a max limit of 20mph!

    If I used bus tracker I could work this out in more detail. Will also need to use that for the 41, as the stop distances on the paper timetables are too far apart to work out for the "20mph" zone.

    Posted 12 years ago #
  6. kaputnik
    Moderator

    @anth, that looks awfully familiar to something that appeared in a not-too-long-ago copy of citycycling!

    Posted 12 years ago #
  7. Funny that, there might be a re-appearance of it in a future citycycling!

    Posted 12 years ago #
  8. Hmmm, Councillor Barry quotes from the February... (with comments...)

    "Britain has some of the safest roads in the world - most of the time these traffic measures are a distraction - I think they have a reverse effect."

    Oh, he thinks they would have the reverse effect, I'm convinced!

    When we put an unrealistic speed limit on a street, people tend to disregard it. And the police seem to be very good at prosecuting drivers."

    Awww! Poor drivers being prosecuted for breaking the law! And unrealistic?

    During the bad weather I had to drive at 20 miles per hour. I was in third gear all the time when I could have been in fifth or sixth."

    Er... Could have been in 5th or 6th? Presumably not in a 30 zone that was being considered for a 20???

    My fuel consumption went up by nearly 50%. So this speed limit could increase pollution in the community.

    50%? 50%?!?!? That, sir, I contend is tosh of the highest order.

    Questioning the positive results of the Portsmouth scheme, Councillor Barry said: “I don’t think the figures actually stand up – I don’t know what the circumstances were in Portsmouth before this."

    Well why don't you find out before spouting off about them?!? Hmmm??? You don't think they stand up, so what are you basing that thought on? Maybe, just maybe, in Portsmouth they hit upon a good idea.

    Cars stop in half the distance now than they did 20 years ago – that’s the reason accident rates are coming down."

    Hahahahahahahahahahahaha! That is all...

    Posted 12 years ago #
  9. Klaxon
    Member

    Hey

    I've been a lurker here for at least a year and never registered because on the whole I don't identify as a cyclist however in the fair weather months I do commute so. Reading this topic however has infuriated me greatly, particularly your posts Anth where you are quick to tear into the Cllr's points ad hominem however make no attempt to explain why he is incorrect in his views. He's completely right in saying by setting a speed limit too low for what can be subjectively considered reasonable by drivers compliance is low and it criminalises those whom have no business other than correctly using a motor vehicle. On a clear road at off peak times it's reasonable to go at 30 in 5th, it sacrifices an element of control for fuel economy.

    The fact there have been negative aspects of the Portsmouth experiment is raised but instead of finding out farther what these are and providing some judgement as you suggest the councillor does, you just again personally attack him.

    Please could you stand off your soap box and explain to me why, in objective terms applicable to all road users, why lowering main road speed limits is a good thing.

    Posted 12 years ago #
  10. Dave
    Member

    Klaxon - what is considered reasonable by drivers is just a product of conditioning. If the current limit was 40mph and we were trying to reduce it to 30mph, someone like yourself could make the exact same arguments with different numbers.

    Bearing this in mind, you might agree that the ultimate effect of blanket 20mph limits on the next generation of drivers will be for people to consider it the norm and be happy going at that speed. It's a cultural shift, sure - and so by definition it goes against the current norm.

    The phrase "criminalises those whom have no business other than correctly using a motor vehicle" is also subjective. Thirty years ago people would defend drink-driving in just those terms - it was common practice and there weren't *that* many extra deaths, why criminalise the ordinary law-abiding driver who just had a few pints at the local?

    Nowadays being caught drink-driving is not far above paedophilia in the public mind. Now, speeding because you feel it's reasonable when society has decided to try and reduce vehicle speeds is simply law-breaking. There are all sorts of other laws that I'd love to break (tax evasion, ignoring planning permission regulations, the list goes on) and I could make a pretty good argument that it would be a victimless crime in many cases, but I still don't get to do it. Only in the area of driving tons of metal past people's houses and businesses do people come out with the odd idea that they should be able to choose how they do it and are unfairly victimised when society enforces laws to restrict Mr Toad.

    Posted 12 years ago #
  11. Dave
    Member

    Aaaanyway. I really just came on here to enclose my reply to Councillor Taxi:

    Hi Eric,

    Thanks for your thought-provoking response. I wasn't aware that polar bears were anywhere on the committee's agenda versus the safety of our children. You live and learn.

    I took the liberty of putting your 200 bus journey days in the context of the overall amount (using the figures you provide) and calculate that this represents an increase of just 0.05% - what a lot of buses we have!

    Happily, there will be no increased emissions as the result of a 20mph limit. The Transport Research Laboratory demonstrates a basically constant CO2/km figure for buses at the speeds we are talking about. Even for private vehicles we must balance any possible decreased efficiency at 20mph with the savings on acceleration and deceleration that come with the smoother traffic flow.

    On which topic - I can think of several sets of lights on the affected bus routes which would arguably no longer be necessary under a 20mph limit. Potentially these lights could be removed to save our buses from untold minutes of delay. I daresay in most cases the buses would save more time than was lost, or at least mitigate the paltry time losses we're talking about.

    You've also missed the obvious point that as conditions become more pleasant for folk not in cars, we would expect to see a fall in car use and as these are invariably single occupancy (or school run), a great saving in terms of congestion and pollution would no doubt follow. At the moment I spend half of my drive to work in Leith waiting for other people to get out of my way!

    Bearing all of this in mind, you will understand why ordinary folk find yesterday's decision to display a disturbing lack of vision.

    Kind regards,

    Posted 12 years ago #
  12. chdot
    Admin

    @Dave

    Well put - both posts.

    Unfortunately -

    "Proportion of young drink drivers increasing"

    http://www.telegraph.co.uk/motoring/news/8675865/Proportion-of-young-drink-drivers-increasing.html

    Posted 12 years ago #
  13. "The fact there have been negative aspects of the Portsmouth experiment is raised but instead of finding out farther what these are and providing some judgement as you suggest the councillor does, you just again personally attack him."

    Because the councillor has been elected into a position to represent the people and as such when making a decision on a matter is duty-bound to inform himself correctly of the facts rather than basing decisions on what he thinks and attacking good results achieved elsewhere while admitting that in the same breath/keystroke that he hasn't bothered to look into those facts to make sure he is attacking correctly.

    I, meanwhile, have not been so-elected, and have no such duty, however I've still, very quickly and easily, been able to avail myself of more facts than Councillor Barry has seen fit to even try and find.

    Councillor Barry is an elected representative.

    "Please could you stand off your soap box and explain to me why, in objective terms applicable to all road users, why lowering main road speed limits is a good thing."

    Quite simply because less people die, and streets are, to a certain extent, reclaimed. I'm not actually too concerned about this as a cyclist, more as a pedestrian. Crossing the road in Beirut is easier than Edinburgh! (and yes, I've done it - traffic in Beirut just stops for you - takes some courage, but it's an interesting concept).

    As a driver (anyone on here will tell you I'm probably one of the most petrolheaded cyclists around) I've got a wee sports car that could make a mockery of any city centre speed limit. But it doesn't. Because I'm driving it. The streets all round my house are 20mph, not that most (even with traffic calming measures around) would have you believe it. I drive at 20. Strangely my fuel consumption hasn't hit astronomical levels. Nor has my gearbox dropped out the car (on the specific engineering issues involved I really need Smudge here, he understands these things). Nor do I find myself growing older by the second as I 'potter' along.

    "... it criminalises those whom have no business other than correctly using a motor vehicle."

    That's a Daily Mail standard term that is. It criminalises those who break the law - it is perfectly possible to drive correctly at 20mph, with control. People who are incapable of doing so have no business being in charge of a tonne of metal and glass.

    It's a bit like the argument that a 20mph limit means that people have to virtually stare at their speedo non-stop in order to make sure they comply. Why this is differetn from any other speed limit I don't know, and when I'm driving I find a mere glance every now and then is enough to keep my speed in check.

    Now, if that 'aint enough what I'll do tonight is get some hard and fast statistics and engineering fact. Will you come back to comment on those statistics and facts?

    Posted 12 years ago #
  14. chdot
    Admin

    "Will you come back to comment on those statistics and facts?"

    I suspect he will - obviously likes a good argument discussion.

    Hope so; need more people on here who say "I don't identify as a cyclist however in the fair weather months I do commute".

    It's about CHOICE - and I think most people on here believe that more people would choose if the felt the roads were 'safer' - 20mph would make things MUCH better.

    Posted 12 years ago #
  15. The Atkins report on the Portsmouth scheme looks like interesting reading, proving this most certainly isn't a black and white issue. A map of accidents involving injury pre and post-20mph zone implementation is very compelling though, it must be said (statistically speaking a 22% drop in injuries - countered with an 8% rise in deaths - there is interweb discussion of why that would happen (most reads as 'small sample statistical anomaly' - sheesh, I've given myself a lot of reading, maybe I should stand for election to the Council... ;) )).

    Posted 12 years ago #
  16. Instography
    Member

    Anth, I know I'm being lazy but do you have a link for the Atkins report?

    Posted 12 years ago #
  17. Morningsider
    Member

    Klaxon - you might find the following to be of use.

    Why has there been a drop in road collision casulaties: The recently published UK Strategic Framework for Road Safety identifies three key factors:

    1. Improved vehicle safety
    2. Dedicated road safety engineering projects
    3. A reduction in speeding due to better enforcement, traffic calming and better driver education

    So, no direct mention of braking distances - although it might fall under improved vehicle safety.

    The Portsmouth 20mph scheme: The evaluation of the Portsmouth scheme (http://www2.dft.gov.uk/pgr/roadsafety/speedmanagement/20mphPortsmouth/pdf/20mphzoneresearch.pdf) concludes:

    "In conclusion, early figures suggest that the implementation of the 20 mph Speed Limit scheme has been associated with reductions in road casualty numbers. The scheme has reduced average speeds and been well-supported during its first two years of operation"

    This research project does not seem to have concluded that driving at 20mph rather than 30mph adds to driver distraction.

    Impact on journey times: As Dave and Kaputnik have already demonstrated (and the Portsmouth study also shows) the average speed on many urban routes is already well below 30mph - so implementing such a limit has minimal impact on journey times or enforcement requirements.

    Fuel consumption: Fuel consumption does not increase by 50% if you reduce speed limits from 30mph to 20mph. Even the AA argues that any increase will be around 10% (http://www.theaa.com/public_affairs/news/20mph-roads-emissions.html) and this applies to "free flowing streets" which are subject to traffic calming - not what was proposed in Edinburgh.

    Given all this - I would suggest that Anth was right in his criticisms, even if he didn't have the evidence to hand to back them up.

    Posted 12 years ago #
  18. Tis here Instography.

    Posted 12 years ago #
  19. "... even if he didn't have the evidence to hand to back them up."

    I'm working on that... ;)

    Posted 12 years ago #
  20. chdot
    Admin

    "Tis here Instography."

    Sorry anth, resident person with fingers on research - M'sider - beat you to it AND he says you're right!

    Posted 12 years ago #
  21. chdot
    Admin

    "I'm working on that"

    GREAT

    I think this all could prove quite interesting...

    Posted 12 years ago #
  22. Dave
    Member

    The obvious point to make about gearbox efficiency is that if the prevailing urban speeds are increasingly 20mph rather than 30mph, manufacturers can just optimise their cars for that speed instead.

    One powerful incentive would be to start calculating the urban MPG rating of vehicles based on a 20mph limit. That would strongly incentivise manufacturers because one of their chief sales metrics would depend on optimising emissions for the slower speed.

    It makes no more sense to think of 30mph as a fundamental physical high point for engine efficiency than 30mph as a fundamentally better speed to drive at.

    Posted 12 years ago #
  23. Cyclingmollie
    Member

    Dave: "I took the liberty of putting your 200 bus journey days in the context of the overall amount (using the figures you provide) and calculate that this represents an increase of just 0.05% - what a lot of buses we have!"

    Well done on pressing your councillor on this Dave. It is a classic trick of politicians to present what appears to be a big number but which on inspection turns out to be a really small number. E.G. £5 million for better dental care sounds like a lot until you realise it's less than a pound per person per year - less than a toothbrush.

    Posted 12 years ago #
  24. "GREAT

    I think this all could prove quite interesting..."

    Well... I've grown attached to this wee soapbox... ;)

    "It is a classic trick of politicians to present what appears to be a big number"

    The other trick (used by the media) is percentages. Such as 'Kitten owners 57% more likely to contract cancer!' and you find out that it's a specific type of cancer with a specific type of kitten and 57% equates to one extra case in the world every 13 years.

    Posted 12 years ago #
  25. chdot
    Admin

    "57% equates to one extra case in the world every 13 years"

    YOU MADE THAT UP!

    (Keep up the good work...)

    Posted 12 years ago #
  26. Cyclingmollie
    Member

    "The Tiger That Isn't - Seeing through a world of numbers" by Michael Blastland and Andrew Dilnot has lots of examples of how stats can confuse. We could send a copy to Councillor Barry but he'd probably just learn a whole new set of tricks.

    Posted 12 years ago #
  27. Instography
    Member

    Thanks for the link. It's quite a shoddy piece of research. My guess, is that it was woefully under-funded. Everything about it is methodologically weak - speed surveys on one day, averaging accidents rates over three years without examining a long-term trends, no looking at displacement effects, poor residents' surveys. The lack detail is worrying. If you were minded to it would be quite easy to take it to pieces.

    Broadly, on the data that they have, it seems to show that the scheme achieved what could reasonably have been expected - a small reduction in average speeds in areas where average speeds were already low. You can see why opponents would say it has spent a lot of money to achieve nothing.

    What they don't show is the bit that would have been most important. In any measurement exercise speeds will be distributed around the mean. Where the mean is close to 20mph before and after introduction, what you should be most interested in is examining variation around the mean rather than the mean itself since the reduced variance would suggest that while average speeds are broadly the same, the small reduction in the average will have come about by a comparatively large reduction in the speeds of those vehicles where the 'before' speed was substantially higher than the mean.

    Posted 12 years ago #
  28. chdot
    Admin

    "maybe I should stand for election to the Council"

    Weeeelll...

    Generally 'the system' favours established political parties. Clearly there have been all sorts of new parties - usually via splits or mergers - or with a private benefactor or two.

    SDP through the various socialist splinters to UKIP etc.

    The party with the most interest in this topic is obviously Green (only councillor to speak in favour of full 20mph proposals), but I don't suppose they are looking for candidates for 'winnable' seats.

    SO the alternative is 'as an independent'. Generally not doing too well these days.

    The PR system for the Scottish Parliament made it happen first time round for small parties and single issue candidates. Now with the 'sophistication' of the voters, the collapse of Tommy & Co., and the wising-up of the main parties there's only Margo left - and she's a bit well known.

    At local council level few independents have even managed to get many votes - in spite being 'known' locally.

    There's a local by-election in a few weeks with an independent candidate.

    He's standing on the single issue of the trams. In theory - given 'public anger' - he should get nearly 100% of the votes. In practice I suspect the winner will be from one of the established parties - but not ready to put money on which one!

    Next year might be different. Our esteemed Council Leader is standing in a different seat, which may or may not be due to the fact an independent is planning to stand in her current seat on the issue of a school closure! http://edinburghnews.scotsman.com/topstories/Big-names-to-quit-council.6811582.jp

    If you asked people (in Edinburgh) if they would vote for "none of the above" a lot would probably say yes. If asked 'would you vote for an independent if you didn't know them or their policies very well' a lot would say no.

    At various times in various places there have been 'rainbow alliances' but they are difficult to organise and don't tend to last.

    It would be nice to think that a 'we really want the best for Edinburgh and we'll give you free apple pie' party would pick up a lot of votes/seats - BUT...

    I think the best thing 'we' can do (individually and perhaps collectively) is think about some basic issues - more 20mph areas, rapid response pothole teams, more pedestrian crossing that change when people press the button, dedicated/named park keepers for all parks, benches every 1/4 mile on main off-road walk/cycleways (etc. etc. - think I'll start a 'manifesto' thread).

    Then - next year - rationalise it, maybe get groups like Living Streets, the AA, Friends of Corstorphine Hill (random selection!) to back some or all of it, put it online ask ALL candidates to tick whichever boxes they agree with and have the answers publicly visible...

    Posted 12 years ago #
  29. chdot
    Admin

    THIS IS GREAT.

    "Where the mean is close to 20mph before and after introduction, what you should be most interested in is examining variation around the mean rather than the mean itself since the reduced variance would suggest that while average speeds are broadly the same, the small reduction in the average will have come about by a comparatively large reduction in the speeds of those vehicles where the 'before' speed was substantially higher than the mean."

    I (almost) don't understand it - but means 'we' won't get bamboozled (technical term) by officials selectively using statistics (if they have them in the first place!).

    Posted 12 years ago #
  30. "Then - next year - rationalise it, maybe get groups like Living Streets, the AA, Friends of Corstorphine Hill (random selection!) to back some or all of it, put it online ask ALL candidates to tick whichever boxes they agree with and have the answers publicly visible..."

    That, chdot, is a startlingly good idea. Count me in for helping with that.

    I did actually seriously consider standing as an independent a few times (council and MSP level) but it was that whole party-politics thing that made me realise independents are (virtually) doomed to failure before starting.

    Posted 12 years ago #

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