Saturday, 11 December 2010

Letter from America

Well, not quite. I am now back in UK after a trip to New York to speak at the “Stop Speeding Summit” conference hosted by Transportation Alternatives on 19th November. TA are the “not for profit” organisation based in New York who campaign for walking, cycling and public transport options for New Yorkers.

And it is Transportation Alternatives who I really must thank for their invite, funding my visit and also hospitality whilst I was there. This post is therefore dedicated to TA and their on-going efforts to make New York not only a “great city” but also a “great city to be without being dependent upon a motor vehicle”.

Tuesday 16th Nov

I arrived at Newark Airport in New Jersey at about 5:30pm on Tuesday 16th Nov. Getting through immigration was much easier than I had been warned and soon I was on the monorail from the airport to the Train station when I quickly caught the New Jersey Transit line to Penn Station. This was just a few hundred yards from the TA offices on 26th St. West and my hotel which was next door. I met up with Lindsey Ganson who was my TA contact and their Safety Campaign Director.

After a short meeting I checked in at the hotel and then Lindsey and Kim Martineau (TA’s Communications Manager) took me via the subway down to Lower Eastside where Kim had arranged for me to meet a New Yorker journalist the following morning. This gave me an opportunity to experience the traffic on the streets and get some background to TA’s work in New York. We saw some of the bike lanes which had been installed on some of the major streets with the bike lane next to the sidewalk (pavement), a lane for parked cars and finally 2 or 3 lanes for moving traffic.

I then headed back up to mid-town and after having been up for 21 hrs was ready to get back to my hotel and sleep.

Wednesday 17th Nov – Walk around with New Yorker reporter and presentation at Wagner Rudin Center

Next morning I was up early and after breakfast I went out onto 6th Avenue to take in the atmosphere on the streets. What struck me right way was that with wide roads, most one way, the traffic seemed to be very dense and fast. But then suddenly it would all disappear and for about ½ minute or so hardly a moving vehicle was in sight. It seemed that the traffic was running in pulses through the city. At TA I met Paul Steely White who is their Executive Director. Paul gave me some more background to TA and the way that the New York City Dept of Transportation is taking some innovative steps to assist cycling and walking.

Then Lindsey and I went downtown again to meet with Ian Parker of the New Yorker, who was going to do a walkabout with me. I had been given a speed detector by TA and the idea was to use this to check the passing speed of the cars on roads such as Houston St. Ian was originally from England so it was an interesting discussion. His article can be seen at

From there I was presenting at “brown-bag” session at the New York University Rudin Center for Transportation Policy and Management. The term “brown bag” comes from the notion that students would bring their sandwiches (in a “brown bag”) for a lunchtime session. It gave me a good opportunity to practice my conference presentation to the students studying for their masters degrees in Urban Planning.

Later that evening I had dinner with Paul Steely White and Noah Budnick (Deputy Director) of TA. We discussed the next day’s plans for meeting Jimmy Vacca who is the Council member chairing the city’s transportation committee, and also Senator Eric Adams.

Thursday 18th Nov Meeting with James Vacca and walk around with Senator Adams.

And this is when I got to ride a bike around the city. First it was cycling downtown to the very bottom of Broadway. Noah rode with me and I must admit that with all the one way streets I was not conscious of any problem with cycling “on the right”. In fact many one way streets have the cycle lane on the left. The reasoning is that parked cars that you pass are less likely to have the car driver opening their door on you. But you still have to watch out for passengers.

Jimmy Vacca is a hard-working councilman who took over the chair of the NYC transportation committee early this year. A profile can be seen at :-

I introduced myself as someone who could save NYC millions of dollars in costs of road casualties. I knew I had not more than 15 minutes and wanted to ensure that he remembered me. We talked about the campaign and how it helps everyone, especially the young and old. Then Noah and I cycled across the Brooklyn Bridge and down to the Park Slope area. Noah and I just had time for a coffee on a street corner. To be truthful, the scene outside was similar to one in many UK towns. A line of shops, an evangelical church opposite and surrounded by large terraced housing. We then met up with the Park Slope residents on another street corner and talked about their local campaign for a 20mph speed limit in Park Slope. Senator Adams then arrived and we all walked with him around a few blocks, taking turns to discuss the issues. He was very interested in the UK successes of 20’s Plenty for Us. He even used the phrase “paradigm shift”. Here was someone who understood the issues. It was not just about slowing down, but sharing the roads in a better manner. Clarence Eckerson of StreetFilms made an excellent video which can be seen at or on our website home page.

It was really good to see politicians with conviction and vision looking to make their town a better place for their people. Noah and I then cycled back across the Manhattan Bridge, through Chinatown and back to TA. The cycleway across the bridge now has a 20’s Plenty for Us sticker half way across.

Thursday night was spent preparing for the next day’s presentation at the “Stop Speeding Summit” conference. Last minute changes to slides were made including the header slide so that 20’s Plenty for Us morphed into 20’s Plenty for USA.

The presentation was a tricky one. I guess that some of you know that I don’t usually pull punches and here I was a guest in a foreign country charged with asking them to change their driving habits.

Friday 19th Nov – “Stop Speeding Summit” Conference Day

On the morning I walked the couple of miles downtown to the conference. Paul Steely White of TA opened the conference and introduced me as the first presenter.

9:00 – 10:30 Area-wide 20mph zones.

I gave my standard presentation with a few slides taken out to make it a little more compact. To my delight, and relief, the presentation was very well received and the audience had some excellent questions. A report of my presentation can be seen at

Next, Ian Sacs of the City of Hoboken gave a presentation on how they had started to implement their “20’s Plenty for Hoboken” policy. This asks residents in the New Jersey town of Hoboken to voluntarily keep to 20mph on Hoboken streets.

You can see their campaign at

10:30 – 11:30 Panel Discussion: Slower Speeds = Healthier New Yorkers

Several health professional gave presentations on programs they were leading to promote active travel. All saw the speed of traffic as a major impediment to modal shift.

11:45 – 1:15 Remarks from James Vacca, presentation by Dr. Thomas Farley, and the rap.

I was pleased to see that Council Member James Vacca (whom I had met the day before) gave a speech after lunch and pronounced his favour of a 20mph speed limit and the need to make New Yorks streets more attractive and safer for pedestrians. I particularly liked his statement that “the pedestrian is always in the right, even when the pedestrian is in the wrong”.

Dr. Thomas Farley is the Commissioner for NYC Dept of Health and Mental Hygiene. He presented with a focus on the effects of physical inactivity, especially the fact that 1 in 8 (800,000) adults in NYC are diabetic. The lack of active travel is clearly a problem and health professionals are seeing the consequences of inactive travel as an epidemic. For a New York Times report see In the UK health professionals tend to go further than pointing out the problems associated with high speed roads, and predominantly come out in favour of 20mph limits.

I was then asked to give to recite our 20’s Plenty for Us poem which Anna Semlyen (our Campaign Manager) had written for us. I suspect that this was really an opportunity to contrast the “old world” style with the presentation which followed from Dr. John C. Clarke who introduced his “Drive Safe, New York” rap. We have uploaded this excellent sound track to our website at

1:15 – 2:30 Panel Discussion: Automated Speed Enforcement.

The panel discussion on Automated Speed Enforcement was interesting because New York does not have any automatic speed cameras. Various presenters noted how effective they were in other states. Indeed in the UK they are deemed to be effective. However, what is found to work best is a mix of both fixed and randomly placed cameras. The former can reduce speeds on know problem streets, whilst the randomly placed and manned cameras initiate better compliance elsewhere.

For a recent review of the effectiveness of Speed Camera Enforcement in the UK see

2:30 – 3:15 Panel Discussion: Strategic Use of Crash Data

There was a discussion of data led interventions by Baltimore Police Department and the NYC Dept. of Transportation. It was very much about identifying accident spots and what interventions could be done. Like most data-led interventions it tends to ignore the substantial number of un-clustered collisions which can only be addressed with a wide scale intervention. Of course unclustered minor injuries and “near-misses” also play a fundamental role in conditioning vulnerable road users on the dangers that exist in the streets. Focussing on collision hot spots may well make some reduction in casualties but on their own will not change the perceived danger on the roads.

3:30 – 4:15 The Economic Cost of Crashes

Eric Tang of Cambridge Systematics Inc. gave a presentation on this subject and compared the “cost of congestion” to the “cost of crashes”. He quoted that the cost of crashes is higher than the cost of congestion in every US urban area. In New York the figures are Cost of Crashes - $29Bn, Cost of Congestion - $8Bn.

The closing remarks were made by Paul Steely White of TA. I think that the outcome was that attendees were very pleased with the conference and the recognition it gave to the need to address the speed of motor vehicles in New York City.

In the evening Paul Steely White took me to meet some of the USA Cycling team. I was offered a ride out on the Saturday morning but whilst very interested decided that after several very busy days, I would perhaps not be in good enough shape to keep up. Besides, I had specific instructions from my grandson to get a picture of the Statue of Liberty.

Saturday 20th Nov

My day was spent as a tourist, catching the Staten Island ferry, walking around the town and getting a few souvenirs for the family back home. In the evening, I was delighted to be asked to dinner at the home of one of the TA board of directors and met several of the board and advisory council. In particular, I was able to thank the sponsor who had paid the expenses for me coming to New York.

I was told that our campaign had been watched for several years and that it was noticeable how UK was successfully transforming its towns and cities. It was particularly noted how London has used lower speeds to create a better environment for walkers and cyclists.

Sunday 21st Nov

This was my last day, and so I had arranged to have lunch with Lindsey Ganson. Lindsey had not only been organising the whole conference, but had also ensured that my time was filled with the various interviews. It was also Lindsey who I had first spoken to in the summer when she inquired about our campaign in the UK.

We talked about the success of the conference and how it really was seen as a milestone in initiating the debate on lower speeds and their beneficial effect.

After lunch it was time to head back to the airport and travel back to UK, arriving at 7:30 in Manchester on the Monday morning.

Some reflections

On Transportation Alternatives

TA are great advocates for cycling, walking and public transit. Their mission statement is :-

“to reclaim New York City's streets from the automobile, and to advocate for bicycling, walking and public transit as the best transportation alternatives.”

With a staff of 15 and located in the central area of Manhattan, they are really making a difference changing the way in which transport in viewed in the city. With a receptive Dept. of Transportation they are really making headway in changing attitudes. And from my own experience in the city, walking, cycling and public transport are far faster and cheaper than going by car.

They have a young team of very dedicated staff who are all enthusiastic about making change happen. See some of their campaigns at

I therefore thank them for their hospitality and for bringing me across from UK to help in their campaign. The experience has not only gained 20’s Plenty for Us new friends but also enabled us to link with many other advocates of lower speeds in the US. It reminds me that behavioural change in the way roads are shared is actually a universal objective and that whilst our legislation, size of roads, style of driving and even the side of the road we use may differ, the challenges are still the same. And because we all campaign as people rather than cyclists or pedestrians, or English or American, we debate the same values which we attach to the quality of our lives and the freedom to choose our way of moving around our towns and cities.

My thanks go to all the staff, directors and funders of Transportation Alternatives.

On New York drivers!

Before I left, my daughter gave me a book on New York’s history. I leafed through it and found that it was not till page 776 that a motor car was mentioned. Clearly, New York became a great city long before the motor car came about, and I suspect will remain a great city even when the motor car is seen only as a passing phase that was confined to a short period in history.

But the motor car seems to be here for the foreseeable future and in Manhattan it certainly dominates the streets. I reckon that about 75% of cars were actually taxis, and all of them seeking to get as many rides in as short a time as possible. Taxis seem to accelerate up to 35-40mph and above as quickly as possible once the lights change. To them time is money and going fast is seen as the “New York way”. But on the other hand, I heard that within the central business area of Manhattan then the average speed of cabs from 8am till 8pm is never more than 10mph. So for all their pace and speed they must be stopped for the majority of the time.

To me, if you want to reduce speeds in New York then you have to “Tame the Taxi”. Do that and other traffic is bound to be slowed down as well. On the face of it this would seem difficult, yet taxis are highly regulated. Currently taxi fares are relatively cheap. Fitting tracking devices to measure their speed is neither difficult or expensive and fares could be increased slightly to offset any slight increase in journey times. At the same time, slower maximum speeds increase the capacity of roads and also decrease the fuel used and emissions produced.

“Taming the Taxi” would therefore be my approach to reducing prevailing speeds on NYC roads. That, together with lower and enforced speed limits could transform New York and make it an even better place to be. It would also really encourage cycling and walking.

On New York and 20’s Plenty for Us

Well 20’s Plenty for Us has had great success in the UK. We are changing the way our streets are shared and making a real difference in so many towns throughout the country. From what I have seen in New York then its possible there as well. Already the Dept. of Transportation is planning to introduce 20mph limits to a pilot area in the Bronx. We know from our own experience that pilots simply increase the aspiration and demand for the same treatment in other communities. And we know of no communities that once given a 20mph speed limit want it to revert back to a higher one.

The key factors in change are strong advocacy, sympathetic professionals and visionary politicians. Whilst I was in New York I saw all of these. I suspect it’s not a case of whether 20’s Plenty for New York but simply when 20 will be Plenty for New York.

And of course if they can do it there then they can do it anywhere!

My best regards to everyone I met in New York. and special thanks to Transportation Alternatives.

Saturday, 27 November 2010

Walk around Brooklyn with Senator Eric Adams

20's plenty for Us were presenting at the "Stop Speeding Summit" in new York last week. The groundbreaking conference hosted by Transportation Alternatives brought together Transport, Road Safety, Health and Enforcement professionals and Rod King started the conference with a review of the success of the 20's Plenty for Us campaign in the UK.
Other meetings were arranged with New York politicians, activists and officials. In the following video you can see Senator Eric Adams in a walk around the Park Slope area of Brooklyn talking to Rod King and other local activists :-

A Walk thru Park Slope with NY State Senator Eric Adams from Streetfilms on Vimeo.

Sunday, 17 October 2010

Presentation to Transport Planners Society

Last week I was asked to present in a debate on 20mph speed limits in Manchester. Here is a copy of what I said :-

For many years Britain has led the world in terms of lowest deaths per head of population on our roads. But that has led us into a state of complacency. It is true that we have been gradually engineering our roads to be safer. But for whom. Whilst in the Netherlands 10% of road deaths are pedestrians, in the UK it is 22.5% .

Our levels of active travel in the UK are some of the worst in Europe. And in a recent survey by Road Safety Analysis of UK child road casualties it found that for the worst 10 local authorities, 1 in 15 children would be injured or killed on our roads before the age of 16. And 9 of those 10 local authorities were in the North West.

So we may have gradually engineered away many of our black spots, and have better trauma care, and better in-car safety, but for our vulnerable road users we are, collectively failing to meet their needs for free and safe passage on our roads.

We use the term “Total 20” for the setting of 20mph as the default for all residential roads in a local authority. This allows the local traffic engineers to determine the exception as appropriate for local conditions. It does so without putting in additional speed bumps and only “light touch” enforcement. “Total 20” stands on its own merits in terms of cost effectively reducing speeds and casualties.

In Portsmouth we know that on faster roads, where casualties are most common and severe, there has been a 6mph reduction in speeds and a 22% overall town-wide reduction in casualties.

In Warrington the recent 20mph pilots resulted in a 800% First Year Rate of Return when the costs and achieved casualty reductions were analysed.

• We know that 30mph streets will never provide the basis for encouraging active travel.

• We know that children are far more at casualty risk around their homes than around their schools.

• We know that a 30mph limit set in 1934 as better than nothing is now inappropriate for so many of our streets.

• We know that a large percentage of all casualties are unclustered and cannot be addressed by data led interventions.

• We know that whilst speed may only be the cause of some collisions it is implicated in the inability to take avoiding action in the majority of incidents.

• And we know that in European cities the 30kph limit is the foundation of their cycling and walking strategies.

We need a fundamental change,…. A paradigm shift in the way we approach danger on the roads.

Total 20 provides the catalyst for that change. Its starts with the community aspiration for lower speeds where people live. And that aspiration means that compliance is not some driver reaction to a speed limit sign but a conscious lifestyle decision that we should all take steps to make our streets better places for us all. 20 becomes plenty when we see the presence of people for Speed becomes Greed when it dissuades others from walking or cycling due to fear of traffic.

It asks us to recognise that our journey times are hardly affected by our maximum speed but largely determined by the time we are stopped or in congestion.

And it is because that authority-wide decision requires the democratic and political processes for it to be implemented that it forces the community debate and creates that paradigm shift. And this is where the approach radically differs from most “Data led” road safety interventions.

You see there is no constraint in “Total 20” that anyone can rely upon. No guarantees to give councillors. It is “social engineering” rather than “highway engineering”.

It requires a move away from the drawing board and the statistical analysis of past collisions and asks how can we best act as a catalyst for behaviour change. How can we take that universal aspiration for a better place to live and transform that into our society examining its actions and making that “lifestyle decision” to slow down?

How can we transform the aspiration of children to cycle or walk to school and transfer that into their parents recognising that their driving may be part of the problem?

And we need to have faith in the people. And most of all we need to engage with those people. And that is the key to the success of Total 20. The more you do to reach out and engage and debate and discuss and inform and consult and listen, then the greater will be the success.

You see “Total 20” is an initiative that is community led but establishment endorsed. It needs that community leadership. And we know that 75% of those asked, including 72% of drivers believe that 20mph is the right speed limit for residential roads.

There are some key aspects to the “Total 20” approach :-

1) It delivers the benefit of lower speeds on most driver’s home streets. Hence giving them ownership of that benefit.

2) It is consistent with the message that wherever you mix motor vehicles with people then the people must come first.

3) It takes away the current isolated 20mph patches which merely re-inforce higher speeds on the rest of the network.

I have been campaigning for lower speeds on our urban and residential roads since I travelled to Warrington’s twin town in 2004 and observed that their 23% of in town trips being made by bicycle. This was not built on cycle facilities or off road routes, but on a 30kph (18.5 mph) speed limit for residential roads across the whole town in the early 90s.

Since then I have noticed is a huge shift towards the acceptance of lower speeds as a requirement for improving not only road safety, but the quality of life in our communities. So many organisations from Association of Directors of Public Health, to the National Audit Office and now the Dept for Transport say that 20mph limits are needed for residential roads. 20’s plenty for Us now has 60 local campaigns around the country and our feedback from those communities is that more and more politicians and council officers and police are looking to “Total 20” as a modern, cost effective initiative as a response to community aspirations.

But it is simply not enough to just “ask” people to slow down. It needs the establishment endorsement that comes with a mandatory speed limit being set.

We need to leave behind our “baggage” of what didn’t work in the 1980s and realise that our communities have changed.

We need to think way outside the traditional road safety box. We need to recognise that active travel and its consequent health benefits, better road utilisation, a less car dependent culture, lower noise and lower pollution are all valuable deliveries alongside lower casualties.

These cannot and will not be achieved by mere tinkering with a few isolated speed reduction techniques. The obsession with physical constraints creates that isolation. It creates the view that we can drive at 30 mph on most residential roads but only need to slow down occasionally. Indeed it even promotes faster speeds by large 30mph signs at the end of every isolated 20mph zone.

20mph zones with physical calming are 50 times more expensive per km than Total 20 schemes with their authority-wide economies of scale and communities with a collective commitment to safer roads. Or to put it another way “Total 20” allows 50 times the coverage than isolated zones for the same cost.

And I know that some will talk of the need to “manage community expectations”. Otherwise everyone will want lower speeds on their streets. I say harness those expectations, ride the tiger and use it to deliver a better and fairer sharing of the roads.

I know that some of you will be sceptics. Some will say people won’t change. But in towns across the country communities are asking for that change and politicians and officers are delivering it. Portsmouth is proving that slower roads stay slow and faster roads get slower.

The time has come to give all our citizens a “quality street”. Its time to humanise the space between houses which we call streets and give it back to the people who live in those houses.

20 is already Plenty for the citizens of Portsmouth, and Oxford, and Islington, and Newcastle, and Wirral, and Leicester, and Hilden, and Copenhagen, and Brussels, and Amsterdam, and Rotterdam and Ghent and Graz, and so many more. I trust that you also think that its time that we started to make 20 Plenty for our Northwest towns and villages as well.

At 20’s Plenty for Us we would be pleased to help you. Please contact us.

Thank You

Wednesday, 6 October 2010

Statement to Warrington Bourough Council

Warrington Borough Council recently asked me for a statement to go into their report on their recent 20mph pilots. It was as follows :-

Driving slower where people live is nothing new or radical. In fact it is already common in towns and communities all over Europe. Indeed, it was a trip to our twin town, Hilden, in 2004 which made me realise that so many of our attitudes to sharing the streets were unfair to the young, the old, the disabled, the disadvantaged and every one of us who wants their streets to be as much a place to live as to drive. From this came the formation of 20’s Plenty for Us as the national voluntary organisation supporting communities who want better streets through lower motor vehicle speeds.

In Hilden and other European towns the vast majority of in-town trips are made by walking, cycling or by bus. In Hilden an 18mph speed limit on residential roads was put in during the 90’s and became a foundation for active travel. Their children largely cycle or walk to school and drivers accept that a few seconds longer on a journey is no real inconvenience.

The only thing stopping us doing this in Warrington and other UK towns is our resistance to change. Whilst we disagree with the need for the pilots (there is ample evidence that 20mph limits do work), the recent 20mph pilots have shown not only that Warrington drivers will elect to travel slower, but also that residents will feel that their streets have become better places to live. The evidence from other towns which have adopted 20mph across the whole town is that this delivers even greater results. On slower roads it keeps the speeds low and on faster roads reduces it by 6mph or more.

That reduction makes a huge difference in reducing the danger on our roads. And Warrington really is in need of such a change. Every 12 hours in 2009 someone was injured on Warrington roads, every 4 days someone was seriously injured and every 60 days someone died. In Warrington 1 in 26 children will be killed or injured on the roads before their 16th birthday. For child road casualties we are in the worst 25% of towns in the country. This is not simply about reducing pedestrian and cycle casualties, but also motor vehicle occupants as well.

We all know that council budgets are tight, but the cost of road casualties in Warrington is put at £50m per annum. That’s £253 for every man, woman and child and 50% more than most towns of our size. The cost of implementing a 20mph limit throughout the town on all residential roads and excluding arterial roads is just £1m. Whilst it will not instantly reduce our casualties to zero it can become the foundation for making all of Warrington a better and safer place to be.

It will show that we can make the right judgements about what matters to a civilised and compassionate community. It is time for all of us to take a hard look at our collective sharing of roads and simply say that 20’s Plenty Where People Live. And that time is now.

Saturday, 4 September 2010

20's Plenty for Us video by Streetfilms

We were delighted to take part in a video made by Streetfilms of New York.

For more information and to view the video then go to the Streetfilms website page by clicking here.

Many thanks to Elizabeth Press at Streetfilms for her time and efforts.

Tuesday, 27 April 2010

Speed limits reduce deaths, but can they also cause more pollution?

That was the question put by Leo Hickman in his Ask Leo and Lucy column for the Guardian last week :-

There an estimated 450 20mph speed limit zones across the UK, many of which are located near schools. Since the first ones were introduced in 1991, they have become an increasingly popular traffic calming measure. Bristol, Portsmouth, Leicester, Oxford and a number of other towns now have city centre-wide 20mph limits.

Although they cut down on accidents, do they trigger other unintended consequences, such as increased pollution (both carbon dioxide and particulates) and traffic tail-back further afield? As ever, please share your thoughts on this subject below and I'll be back on Friday to add my own thoughts to the discussion.
We replied as follows :-

First, lets deal with this myth about cars being most efficient at 50-60 mph.

A study, by Peter De Nayer, a former AA fuel efficiency expert, involved fitting cars with a fuel flow meter and testing them at Millbrook proving ground in Bedfordshire. He found that a Citro├źn C4 1.6 diesel achieved 99.6mpg at 20mph but only 29.3mpg at 90mph.

The average car consumes 38 per cent more fuel at 70mph than it does over the same distance at 50mph. At 60mph it uses 34 per cent more than at 40mph.

The study, commissioned by What Car? magazine and based on five cars of different sizes ranging from a 1 litre Toyota Aygo to a 2.2 litre Land Rover Freelander, found that the most efficient speed was below 40mph for all five and as low as 20mph for two.

It was found that for most cars there was a variation of between plus or minus 10% in fuel economy between 20 and 30 mph. This was dependent upon gearing and engine characteristics. Hence for steady speeds there is probably no difference between 20 mph and 30 mph when averaged out across all cars.

However, as has been pointed out, it is acceleration and particualrly repeated acceleration that uses most fuel. By capping the speed at 20 mph the ALL acceleration between 20 to 30 mph is removed.

Whilst advocating wide area 20 mph limits for urban and residential areas we would prefer to see behaviour change used rather than speed bumps to control the speed of motor vehciles.

Where speed bumps are used it would seem perverse to reason that one only needs to travel slowly on the bumps and it is expected to speed up between them. If they exist within a low speed limit then it is actually illegal to speed up between them. Hence any argument that claims that speed bumps (where used) causes increased pollution through repeated acceleration is flawed by the fact that such acceleration is at best unwise/unnessecary and at worst illegal.

Reference can also be made to a report on pollution within Belgian 30 kph zones. This suggested that they reduce particulates and may be found at the 20's Plenty for Us website together with a wide range of other pertinent reports See :-

Of course the points made about modal shift to walking and cycling are very pertinent and I endorse the view that streets with 30 mph speed limits will never encourage active travel and will always by child unfriendly.

I do note that the question specifically relates to pollution caused by carbon dioxide and particulates. However maybe we should widen our perspective on "pollution" and ask how much our streets have become blighted by the presence and speed of so many vehicles in those public spaces between the houses where we live.

Rod King

20's Plenty for Us

Leo's conclusion was :-
So, if reducing emissions is your goal, the all-important factor seems to be what traffic-calming measures you use to ensure speeds are reduced from 30mph down to 20mph. It seems there's universal agreement, though, that speed humps are not the way to go.

I think Rod King of 20's Plenty for Us raises some very interesting and valid points on this issue. And I agree with the point made by Rod and others that 20mph limits assists in encouraging a modal shift away from residential streets being predominantly the domain of motorised vehicles and not pedestrians and cyclists. My own vote would be for more, not fewer, 20mph limits, regardless of whether evidence exists to suggest they might create marginally more emissions.

The full article may be viewed at

Sunday, 7 March 2010

Article published in Local Transport Today

The recent DfT report on "Pedestrian casualties in reported road accidents:2008", which was referred to in LTT 539, misses a worrying trend that since 2004 road fatalities in the UK have become increasingly skewed towards pedestrians. From pedestrians being 20.8% of road deaths in 2004 we have seen this increase this every year. (2005 - 21%, 2006 - 21.3%, 2007 - 21.9%, 2008 - 22.5%).

The report identifies that for pedestrian safety the UK does less well than other EU countries based on pedestrian deaths per 100,000 people. In fact, it puts us 8th out of the EU 19. However when comparing the %age road fatalities that are pedestrians then United Kingdom comes 17th out of 19. Only Hungary and Poland are worse. (European Road Safety Observatory)

Whilst absolute pedestrian casualties have been reducing, this has been at a far lower rate than that experienced by other forms of transport. Hence in the UK a road death is more likely to be a pedestrian than any time since 2001. Our road danger reduction is simply not working for pedestrians.

With 96% of pedestrian casualties on built-up roads, then now is the time for radical action to create a "paradigm shift" in the way we share roads with pedestrians, cyclists and motor vehicle users.

Whilst the DfT has recently made steps to encourage the use of lower speed limits for all residential roads through the use of "Total 20" schemes as in Portsmouth, it needs to relax its signage requirements and enable local authorities to make 20 mph the default speed limit (without repeaters) unless otherwise signed.

By providing clear "gateways" to 20 mph limited areas then no additional 20 mph signage should be required. In order to enable progressive local authorities to move forward with "Total 20" then the government should commit to underwrite any current signage erection and removal costs in the event of them retrospectively changing the default signage requirements on a national basis.

Such a move would overcome one of the major factors inhibiting local authorities from implementing this civic and life enhancing initiative. It would also enable them to meet many LPT3 targets at a far lower cost and greater value for money.

Note: Local Transport Today is the publication read by transport planners and officers in the UK.