Thursday 30 July 2009

Shared Space - Coming Our Way

A post today by Martin Jones alerts us to the fact that the Shared Space concept may soon be introduced to some Bristol streets. Park Street and the Clifton Triangle are specifically mentioned. I've blogged about Shared Use before, expressing reservations about the willingness of British motorists to accept the concept.



So what exactly is Shared Space? The principle is quite simple and appealing. All road users share the same space on the street on equal terms and with no priority given to one direction of travel over another (although the drive-on-the-left convention would continue to apply) or to vehicles over pedestrians. So no pavement / road distinction, no traffic signals or give way markings at junctions and no specific pedestrian crossings (since pedestrians can freely cross anywhere, almost as if the whole street were a zebra crossing).

Of course such sharing is only possible at very low speeds, perhaps around 10 mph, and with limited vehicular traffic volumes, especially through traffic. We already have examples in the form of Home Zones, based on the Dutch Woonerf principle, but these have little if any through traffic so cannot be taken as models for how the concept might work on busy streets like Park Street. The forecourt of Temple Meads station is cited as an example of shared space, but it still has separate pavements and of course no through traffic since all vehicles using that space are accessing the station.


Ashford before....

There are some examples in the UK, notable Ashford in Kent where the former ring road has been downgraded to what is claimed to be Shared Space and the results certainly look attractive in still pictures compared to what went before, as described in this post by Tom Vandebilt and as shown above (before) and below (after) here. However it's clear that this isn't pure Shared Space but retains some segregation and priority, notably keeping separate pavement and road (technically footway and carriageway).


.....Ashford after.

I expect that what we might get in Bristol will also be some kind of hybrid, or bastard child perhaps. Neither one thing nor the other, rather like what was done in the Centre ten years ago. Therein lies a danger. We may end up with something which confuses the existing conventions without giving clear guidance as to what replaces them. The Centre has been a road safety disaster with 6 pedestrian deaths in a few years at just a couple of crossing points for precisely that reason.

There is very little practical experience of Shared Space in the UK and virtually none in Bristol, so it is easy to think that Shared Space will be some sort of panacea. But experience elsewhere suggests that results will be mixed at best. Recorded injury accidents may fall but what about low level harassment and intimidation which is not recorded or even acknowledged by the authorities? Such conflict could even become worse as measures that give some priority or protection to pedestrians and cyclists are removed.

I've no doubt that we need to change the conventions of how streets are used by traffic and to change the visual character of our streets so they look like sociable places. But I believe such change must be based on a deeper understanding of the nature of conflict between different road users which does not yet appear to exist amongst the highway engineers who will be entrusted with implementing Shared Space. So watch this, er, space.

10 comments:

Anonymous said...

"We already have examples in the form of Home Zones, based on the Dutch Woonerf principle, but these have little if any through traffic"

You should check your facts

Chris Hutt said...

And you yours. What point are you trying to make?

Tim M. said...

Haha, Park Street of all places! Hilarious.

It's not that I don't like the Shared Spaces idea in principle, but Park Street - really? Not only is it a major thoroughfare, but it's also quite steep - not exactly the best setting for such a thing. I think pedestrians and cyclists must be on an equal footing, so to say, for this to work.

If someone wanted to improve Park Street, they could make it a one way street. Even if it was two lanes with a landing in the middle, there'd still be enough space left to widen the pavements a bit (funding and traffic re-routing issues aside).

Also: the Temple Meads station forecourt cited as an example of a de facto Shared Space? Really? Does whoever said that ever walk to the train station? IIRC it has been labelled as an area 'hostile to pedestrians' in a study not too long ago, which sums it up pretty well. (I believe it was the 'Area Development Framework' document on http://www.plot6.co.uk, but I'm not entirely sure. That document is a great read in any case btw.)

And the Horsefair shouldn't even be considered for a Shared Space - it should be closed to non-Bus/Taxi traffic entirely (and maybe even to those as well).

David Hembrow said...

Woonerven are just fine. They're a concept from the 1970s which is very common and works very well. Residential streets are for the residents. There's a video here showing what it's like in a housing estate built specifically along these lines.

Shared space in areas with high levels of through traffic are a much later idea, and a less successful one. It's very unpopular over here. They've lead to "might is right" returning to the streets, and it's normal for cyclists to avoid the areas. I could ride through one on my commute - but like most cyclists I take a parallel cycle path.

Watch out for speed limits being reduced at the same time as streets are redesigned. It's a good way of getting the promised accident reduction regardless of what has been done to the streets. Also expect the unpleasantness to rise after a few months or years once the novelty has worn off.

Oh, and even though I live almost in the epicentre of shared space in the Netherlands, I've yet to see a single example of a "pure" shared space where there are no pavements. Most of them actually have formal crossings etc. as without them pedestrians found it impossible to cross the road.

To summarise: it's a (mostly) failed experiment. The Dutch have moved on...

The principle of residential streets being for people (woonerven) has stayed, though. That worked.

Chris Hutt said...

Thanks for that David. As always it's very valuable to have feedback from the Netherlands.

What you describe certainly rings true with me. I suppose making somewhere more difficult for cyclists will tend to divert cycle flows away, as you describe, which would lead to a lower 'accident' rate in the Shared Space zone.

I think it's inevitable that it will be tried more extensively in the UK, irrespective of failures elsewhere, since highway engineers and consultants must always have a new panacea to offer us when the previous one is exposed as just a placebo, otherwise we might well conclude that they're useless.

Unknown said...

Try googling/visiting Cowley Road in Oxford. 20 mph limit, road narrowed and raised to pavement height, artificial curves put into the road to try and slow traffic. Absolutely horrible - instead of overtaking when safe cars now take the slightest opportunity to try and force their way past.

Chris Hutt said...

Thanks St-Werburghian for info about Cowley Road, Oxford. the scheme can be viewed on Google maps and Google Street View via this link

http://tinyurl.com/l6qcg4

It's not what I would call shared space, more traffic calming with nominal 20 mph zone. Lots of buses so not much like Bristol!

Al Shaw said...

I guess the danger you are raising is that if the idea is implemented badly, without proper thought, it's failure risks discrediting the concept in the future.

I agree that thought before action seems in order in this untried area.

Chris Hutt said...

I think you're spot on with that comment Al.

A similar thing happened with 'traffic calming' and even 'home zones'. The idea sounds great in principle but the implementation by highway engineers tends to focus on the physical measures and not the behavioural change.

So we got 'traffic calming' measures which didn't actually achieve the desired behavioural change and in due course I suspect we'll get 'shared use' measures that don't either.

I think it's vital that 'shared use' is carefully defined in terms of the performance it is expected to deliver so that we can assess the effectiveness of any schemes.

Ian Perry (Cardiff, UK) said...

I have an alternative view from the Netherlands of shared space to that of David Hembrow. I too cycle on a combination of segregated cycle paths and shared space. The Dutch built segregated cycle paths to ensure that cars have an infrastructure free from cyclists and pedestrians and this is legally enforced. The Dutch cycle paths are for cars, giving cyclists (and moped riders) 1.75 metres of space to several metres exclusively for cars. Cyclists wishing to turn left have to cross the cars space at designated points that are often inconvenient and sometimes enforced by hedges and ditches between the cycle path and the road.
Cars and light vans are easily able to mount kerbs to park so as not to obstruct cars and they do, even here park on cycle paths, forcing cyclists to dismount, and wheel their bicycles up and down the kerbs and around the parked vehicle(s). As in the UK, not blocking the path of other motor vehicles is of paramount importance to the motorist.
In the UK, cycle lanes are often narrower than a bicycle and many cyclists would like the paths/lanes of the Dutch or Copenhagen’s, however, in Copenhagen only 40% of cyclists are satisfied with the cycle path width and capacity. Increasingly, cargo bicycles are used to carry children and goods. In Copenhagen. 25% of families with two children and 6% of all households now have a cargo bike and this is increasing. 22% of those with a cargo bike, use it instead of a car and 24% use it in addition to a car, thus the cargo bike is reducing car use.
Research suggests that cyclists make better shoppers, shopping more frequently and having greater disposable income to invest in the local economy than those who invest in private motorised transport.
Cargo bikes are wider and slower than traditional bicycles and other cyclists are unable to pass them on many segregated paths. Perhaps segregated paths (and lack of suitable parking provision) are hindering their adoption.
If we are serious about reducing the numbers of cars on our streets, we need to build infrastructures for alternatives to the car. The segregated cycle path is not an infrastructure for cargo bikes and even in Copenhagen and the Netherlands there are issues with segregated cycle lane capacities, whilst cars get more space and can carry less people.
The safety record of shared space in Ashford, Kent is excellent as it is in the Netherlands and Germany. By appearing to be more dangerous, it is safer as most people take more care. Cars do stop and wait for pedestrians to cross at points convenient to the pedestrian and vehicle speeds are much slower than on typical high streets.
Shared space can also be found in Freiburg (famously in Vauban), Germany, as can naked streets (in Wiehre), where cyclists and motorists safely share the unmarked streets and speeds are restricted to 30 Km/h. UK car parks are further examples of shared space.
To those opposing the shared space scheme for Bristol, why is it not wise for the council to be investing in infrastructure projects that are helpful to cargo bikes, maximise street capacity for cyclists, liberate pedestrian movement and make our streets places to enjoy? Do we have to design our streets and lives around a minority who might want to drive cars without consideration for others and park their metal boxes conveniently for them?
The slope of Park Street should not challenge the modern bus excessively and the scheme should work as in Newcastle city centre and Newbury where buses and a few other vehicles pass through an otherwise pedestrian area. By deterring motorists from using Park Street, and thus simplifying the road network, there will be benefits in congestion levels around Bristol according to Braess’s paradox and without traffic lights (where green means go) be safer than the disaster that was (and is) The Centre.