Sunday 7 December 2014

Chickens, eggs and elephants

Not for the first time in my career, I'm spending the run up to Christmas writing guidance on the design of cycling facilities. This time its part of the government's commitment to 'Cycle Proofing' and strengthening the Highways Agency's responsibilities to 'cycle-proof' all of its new roads. The stakes are high. A £15 billion budget for new roads offers the potential for some amazing new cycle infrastructure - bridges, tunnels and miles of segregated tracks. Imagine, a new tunnel for the road past Stonehenge should leave us a magnificent traffic-free route along the current road alignment. The theory is that with better guidance and education, traffic engineers will suddenly see the light and automatically provide cycle infrastructure. So will the 'egg' of guidance give birth to the 'chicken' of infrastructure?

Also not for the first time, I'm finding that the existing guidance contains a familiar set of instructions for planners and traffic engineers: - 2.0m wide cycle lanes, 3.0m wide cycle tracks, 2.0m wide footways, adequate headroom at tunnels and overhanging signs, no sign poles or lamp columns within the cycle track, no sharp corners or steep gradients and a requirement for every new road scheme to undergo a 'Non-Motorised User Audit' at each stage of design. It's all there in the existing documents from the 1980s up to the last revision in 2005, but it continues to be ignored. Indeed, much of the source material for the IHT Cycle Friendly Infrastructure guide and Sustrans National Cycle Network Guidelines and Practical Details, both published in 1996, was derived from the 'Design Manual for Roads and Bridges'.  On my desk I have a copy of the 1946 Ministry of War handbook for road design in urban areas that features many 'Dutch style' treatments of cycle tracks, separate footways and elevated road junctions with the cycle tracks and footways passing beneath at ground level. So our rewriting exercise is not coming up with many amazing new ideas, but is trying to move from 'advice' (i.e. you may do this)  to 'requirements' (i.e. you must do this).

1970s segregated cycle track and footway designed in accordance with existing UK DMRB



Cross sections from a 1946 UK handbook on road design

Engineers like standards i.e. a beam carrying X amount of weight has to be X dimensions with a load bearing capacity of XX. It is clear and unambiguous and enforceable by regulation if necessary. But what about where a countryside route for horse riders, walkers and cyclists crosses a new trunk road? Each user has different requirements for the ideal surface, headroom and preferences for lit/unlit. Is the route primarily for leisure or transport or both? If for some reason (e.g. a steep hill) we cannot meet the standard for one type of user should that user be banned and forced to take a more circuitous route? This requires judgement and experience, but the 'safe' option in the minds of many engineers is to do nothing because the 'standards' cannot be achieved.

Making the guidance more prescriptive could therefore actually lead to less cycling infrastructure being created, particularly when trying to retro-fit on existing roads where ideal dimensions cannot be achieved.  This is sometimes exacerbated by the consultation process, because campaigners are able to 'mock' the local authority or Highways Agency for failing to live up to its own design standards. The highway authorities therefore choose not to even try to do anything.

As always our brief is to include 'good practice from abroad' but on strategic roads there is not that much to say. We need some segregated space (not shared with pedestrians or motor traffic), a cycle track of minimum dimensions 2.0m one-way or 3.0m two-way is sufficient to accommodate all but the highest flows of cycles, and at junctions we don't want to turn across multiple lanes of traffic without the protection of a separate traffic light phase for cyclists or a bridge/subway.  Also, cyclists can't turn at right angles, see through walls or ride up a flight of steps, so no sharp corners or steep gradients please. So that's the design guidance in two sentences!

I do not believe the view that that traffic and civil engineers are too stupid to design cycle infrastructure. They design some pretty complex and amazing arrangements and structures for motor traffic. I'm sure that given sufficient political priority and an appropriate budget, they could indeed 'cycle proof' every new road and do a fairly decent job just by following existing guidance on what to do for cyclists going along or across high-speed, high-flow roads. The existing guidance includes advice to acquire land outside the highway boundary in order to provide for cycling where space is constrained, for example along the edge of a field on the other side of a wall.

The latest round of schemes coming forward from the 'pinch point' funding does not fill me with optimism however. Cycling does not seem to be part of the design brief. The aim is all about moving more motor traffic through a space. There is no recognition that moving cyclists and pedestrians more efficiently and safely might also be good for the economy and help relieve congestion. If cyclists are mentioned at all, it is usually only with regard to safety and their position as 'vulnerable' road users or 'slow modes'. Yet many of these 'pinch points' are at the edges of towns and cities where local traffic is using the strategic road network for short journeys that should be possible by bicycle. Ironically many of those drivers will be driving (and creating the congestion pinch point)  because they are afraid to cycle in the heavy traffic. Providing for cycling is almost always viewed as an additional 'cost burden' to a scheme (along with moving newts and planting trees), not as something integral that will make the scheme perform better.

The major issues that prevent good cycle infrastructure are not to do with design guidance. One significant hurdle is the scheme appraisal. Trunk roads mainly run through rural areas where there are few local trips, and certainly very few walking and cycling trips. The guidance documents for 'non-motorised user audits' and for environmental and financial appraisal suggest gathering data about the numbers of pedestrians, cyclists and equestrians using existing routes affected by the new road. These are unlikely to ever amount to huge numbers, so the economic case for investment will always be weak. This is like saying that we won't provide access for wheelchairs on trains, buses etc because our surveys indicate that only one in every xxx,0000 train journeys involves a wheelchair user and that valuable space on the train is being wasted. In some cases, a projected increase in cycling and pedestrian use will also generate a predicted increase in accidents, and this has a negative impact on the cost:benefit ratio, so making the business case around growth in the numbers cycling isn't necessarily the answer unless the overall health benefits of more people cycling are added into the calculation!

Regardless of the business case, there must be universal provision for walking and cycling alongside and across every newly built road that is accessible to these modes.  We should also as a nation be considering whether other transport corridors such as land alongside motorways, railways and 'easements' and service roads for major pipelines, pylons and wind turbines offer the opportunity to provide new routes for cyclists. One thing that history has taught us is that our transport infrastructure constantly evolves, and many of the strategic 'A' roads of the 1930s have now become local roads, but are not well designed for local users, while many of the disused rail corridors have been reborn as cycle routes. We should not allow the short term saving of 'value engineering' on individual schemes to undermine the long term benefits of creating a national cycle infrastructure network, yet on existing major projects, the provision for walking and cycling is often seen as an opportunity to save money using sub-standard alignments and materials.

The second major issue is capacity. All of our most 'useful' roads are inevitably full during peak travel times, always have been and always will be. Good new roads induce more trips because they make car travel faster and more attractive and this adds more traffic to existing roads. Where new roads and the old roads meet, a new 'pinch point' is created. These pinch points often become the location at which the cycle route infrastructure falls apart and cyclists are forced onto a busy junction with no protection.  It is not always possible to simply build a bigger junction to increase capacity.  In any case this is in conflict with emerging lessons from cities around the world that are reducing the amount of traffic entering urban centres in order to make them more attractive places to live, work, visit and invest.

This is the elephant in the room. Most 'experts' now agree that car based towns and cities have had their day and failed to create the conditions in which people can live happily and prosperously, but national and local politicians in the UK continuously invest in infrastructure that makes driving easier, and oppose any reduction in car parking space or junction capacity. In doing so they continue deny us the space to make good infrastructure for cycling on existing roads.






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