Thursday 21 November 2013

Time for Cycling


With Dr Who back on the TV this weekend it’s a good excuse to be all timey wimey. Cycling requires travel in both space and time after all. There are two elements to every journey, the distance and the time it takes. In cycle racing the one who gets there quickest is usually the winner. People generally want an easy life and will happily choose to cycle if it is as safe and convenient as driving, because in most towns and cities cycling is already quicker and more enjoyable.
So what has this got to do with infrastructure? Well, the battle over ‘space for cycling’ is well understood. It’s pretty clear that squeezing onto a narrow road or busy junction with fast moving cars and HGVs is unappealing to many people. Physical separation by getting rid of excessive traffic in town centres and residential streets, or by creating cycle tracks and crossing facilities where traffic speeds and volumes can’t be addressed, is the solution.

However physical segregation presently comes at a price when cyclists cross the path of other traffic. Many cyclists won’t use existing cycle tracks because they involve lots of stopping and starting.  There is an advantage in staying on the carriageway where you can keep moving. The penalty for increased separation is decreased convenience, additional effort to stop and start, and therfore additional journey time through delays at junctions. It doesn’t have to be that way, but to take full advantage of more space for cycling we also have to win more time for cycling. Dedicated time is one of the ways in which cyclists and pedestrians can be physically separated from vehicles turning across their path.
It only takes cyclists and pedestrians 5-10 seconds to cross a road or junction from a standing start. Most people no matter how young or old can lap the Manchester Velodrome in less than 30 seconds, but if you’re good, you can do it in half that time.  You’d think that traffic signals would be set to cater for the average, rather than the Olympian, to pass through a junction without other traffic bearing down on them. However time for motor traffic is regarded as sacrosanct by engineers keen to avoid (or not exacerbate) delay to drivers so if you’re a pedestrian or cyclist, you have to be quick off the mark. 

Similarly delay while waiting to cross a junction is invariably passed to the pedestrian and cyclist because you can of course ‘stack’ hundreds of pedestrians and cyclists in to far less space than is taken by a few queuing cars, and then force them to sprint across the road. As well as creating chaotic and unpleasant conditions for pedestrians (and ideal conditions for city pick pockets), these delays are especially disproportionate given that people are usually only walking and cycling short distances and could easily spend half of their journey time standing still watching moving traffic. Living Streets are highlighting this in their current #timetocross campaign because for an increasing elderly population, running across the road in a crowd of people is impossible as well as unpleasant, but all that could be resolved with just 3 more seconds for pedestrians at crossings. For cyclists, a 3 second head start would be enough to avoid many 'left hook' collisions where a vehicle turns left into cyclists going straight on at traffic lights.
Unfortunately, even relatively minor junctions such as supermarket exits usually feature a ‘pedestrian refuge’. That tiny, cramped island fortress of guardrail in the middle of every busy junction. Is it really a safety feature? Or is it there to enable traffic to have the maximum time at the junction, while pedestrians and cyclists scurry across in the gaps between.  The ‘staggered’ refuge that requires a sharp turn and an unpleasant rest in the middle of the road is entirely to serve ‘capacity’ requirements of motor traffic and is invariably unsuitable for conversion to a toucan crossing, which is one of the only legal options for creating segregated cycle crossings in the UK. However, making this into a straight across that is convenient for cyclists and pedestrians is often refused by traffic engineers and network managers because it would require additional crossing time and delay motor vehicles. If we are to have more segregated cycle infrastructure in the UK, we have to have direct crossings, with separate flows of cycles and pedestrians able to cross a carriageway in one single movement. Current UK legislation doesn’t even cover how to sign and mark these parallel crossings hence the DfT is unable to publish design guidance!  

The target for the number of stops per kilometre at junctions on a main cycle route in the Netherlands is zero. Of course in a big city this target is never achieved, but it is an indication of the absolute priority given to pedestrians and cyclists in the design principles and in transport policy.
In the 1950s, 60s and 70s British engineers did at least give some thought to this by providing bridges and subways for pedestrians in New Towns and in ring road systems, just that they got it the wrong way round.  The cars should have been made to go up and down and the pedestrians and cyclists stay at ground level. Or at least there should have been a halfway house compromise, to avoid the damp, dark, indirect, crime ridden subways  and bridges that have given the concept of grade separation a bad name among pedestrians and cyclists.

There really is no excuse for the paucity of time allocated to non-motorised users. It is possible to design traffic lights that offer a ‘green wave’ to cyclists in just the same way that we currently do with SCOOT for motor vehicles.  A detection loop on a cycle track can trigger the lights to change on the approach to a junction so that when the cyclist gets there they have a green light amd don’t lose momentum, and this can have a push-button  back up system in case the loop doesnt detect that snazzy carbon fibre bike of yours.
It is possible to design side-road , junctions with ‘tight’ geometry – angular kerbs, speed tables and narrow entrances, so that cyclists and pedestrians can be given priority and turning vehicles have to wait until they can safely manoeuvre. It is possible to continue the footway and cycle track over a side road entrance and make vehicles give way and bump up and down to cross it, instead of always making pedestrians and cyclists do the crossing no matter how minor the junction.

 It is possible to give right-turning cyclists a safe space to wait on the nearside and a dedicated time to cross, avoiding the need to cross moving traffic lanes and wait in the middle of the road.
All of these things are possible, but crucially they require time.

There is still a possibility to get this right in new road schemes. For existing junctions in busy towns and cities however, cyclists and pedestrians need to engage in the Time War to ensure that safe space for cycling also means a similar level of priority and convenience for cyclists as is offered to motor traffic. That takes political courage and a recognition that its time to treat cycling and walking as legitimate modes of transport that can achieve the objective of efficiently moving people (not just vehicles) around congested towns and cities.

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