Sunday, 7 January 2018

It's A Network Problem

I've been following the debates around a few of the higher profile "streets" schemes as they go through public consultation and the thing which is striking me most is that the consultations rarely mention the wider network and nor do many of those debating the issues.

Much of the problem (I think) is the way in which consultations have turned into mini-referenda where the public is invited to choose sides with the inevitable loss of the "yes, but" or "no, unless" views which can be the ones to offer different insights. It's also about the nature of the things being consulted on which are often corridor-type projects (regardless of mode) where area projects would be more appropriate.

There are so many examples to pick on, but in London, Transport for London consulted on "cycle superhighway 9" which includes cycle tracks on Chiswick High Road. Those in favour of the scheme describe the existing situation which is hostile towards cycling and those against raising a whole list of reasons, but essentially, they're not liking the threat to the motor-centric status quo (and yes, I am biased). 

In my experience, those against a scheme often have far more to say than those who support and it is easy to see how decision makers are influenced by the volume of objection in terms of noise and points made! However, in these consultations, there are some voices where people are raising genuine concerns about displacement of through (motor) traffic onto side roads, the impact on bus journey times and that loading/ servicing of commercial premises will be more difficult.

There will be people against change and no matter what you tell them, that is their position and effort to try and influence their view is on diminishing returns. People with genuine concerns can be brought along and this must mean looking at the issue from a network level. For example, if we know there is going to be traffic reassignment (at least initially), or perhaps more importantly there is going to be a perception that this is going to happen, then perhaps we should build that into the scheme. 

This is not to say that I'm advocating a position of where we should accommodate everyone's view, it is simply not possible, and with that, it must go back to a conversation about what our streets are for and to for those making decisions (and their advisors) to be honest with themselves and the public at large. With CS9 though Chiswick, some people have said that support protecting cycling, but not in that location. 

Even if you don't know the area, you can easily see from a map, that the alternative is to stick people on the A4 which is not somewhere that space is going to be reallocated or on a wiggly route around backstreets where every modal filter proposal will end up as a mini-refurendum!

Looking at this as a network issue, we must set out our broad priorities for the area. At one end of the scale, we have the A4 which is about getting longer distance (motor) traffic into West London. At the other end of the scale we have residential streets which should not be there to provide capacity for through traffic (although many people would disagree with me there). 

Then we have Chiswick High Road. Like many similar streets in the UK, we have the tension between people wanting to use it like the A4 and people wanting it to be a local street serving the community. The problem is that one cannot ever be fully compatible with the other. If we treat the High Road as a movement corridor, then we are going to need traffic signals at certain junctions to deal with conflict and controlled crossings to give people a fighting chance to cross. 

We are going to need bus lanes if we are to prioritise public transport (we don't always). We are going to have pressure for on-street parking and loading. We are going to have pressure to have wide footways (because it's a shopping street). We are also going to have pressure for the other things like nice street trees, tables and chairs in front of cafes and occasional maintenance and utility works.

By trying to permit everything in places like this which have evolved over many years, rebalancing space towards any one mode (regardless) will have an impact and and unless we think about the network as a whole, this impact will be felt over an area which is why we should think about the area as a whole.

We don't seem to like prioritising in the UK. Many local authorities will have a hierarchy of movement - here's Hackney's which I reproduce just as an example, rather than a critique;
  • Pedestrians
  • Cyclists
  • Public transport users
  • Freight distribution (local)
  • Car users (multi-occupancy)
  • Car users (local)
  • Car users (non-local) 
The problem with this approach is two-fold;
  1. Having a hierarchy is one thing, applying it is another,
  2. It's a one-size fits all approach which doesn't recognise the network approach.
Clearly, we are not going to prioritise pedestrians on a road like the A4 and to suggest we are is nonsense. Depending on what such a road connects, we may not even need to put pedestrians at the top of the hierarchy. For example, if the road has direct pedestrian access every 2km or so, then perhaps we have a cycle track which pedestrians might occasionally need to access (say to bus stops). In that situation, we provide a legible and separated layout where people walking need it most (between the access point and the bus stop) and the rest can be a shared-use cycle track.

In our residential area, we might rightly put pedestrians and then cyclists at the top of our hierarchy, but public transport, freight and non-local car users are not going to feature. Perhaps the hierarchy needs to explicitly mention school children as they may be prioritised above local car users (and to be fair to Hackney, they have schemes where pedestrian zones are in force around schools as school travel times).

If our High Street follows a hierarchy like this, it is not going to be possible to include all users (because space is a finite resource) and so we need to prioritise. Walking, cycling, public transport and local freight must surely be the most important and the ones we can fairly easily accommodate. For private car users, we create a motoring grid to get them to and from the A4 (for example), but if we are to prioritise the High Road for the modes I have suggested, people cannot expect to easily drive along its whole length.

Where we keep trying to accommodate everyone (and fail), we continue with enabling people to drive short journeys and this leads to the regular issues of congested High Road type places and "rat running" in side roads. If we looked at change at the network level and prioritised properly, we would surely be able fairly accommodate sustainable travel modes, make quieter residential streets and also make our High Roads nicer places to linger, while dealing with essential servicing.

The other thing to grapple with is the issue of "we don't have a problem". The best example is where a controlled parking zone is being considered. Those in the core of the area have an issue, but at a distance away, people won't. The problem is, that a smaller CPZ will push the parking issues to the fringe and those who didn't have a problem now do. Rinse and repeat. 

The problem here is properly admitting to those that don't have a problem now that they will and that is why a comprehensive scheme is needed. A streets scheme is no different and only by looking at the network can we foresee what the issues might be and then challenge them head on. If it means we have to be a little slower in design and consultation terms, then so be it.

Perhaps looking at the network will mean that once we decide what we are going to do and how we are going to prioritise (once we have consulted), then we have a plan which we can stick to. We can use temporary materials to rebalance and reclaim space as it allows us to cheaply tweak things if there is an issue, and then we can gradually upgrade an area as funding permits (while noting there will be big ticket changes needed). 

This approach could also align with the needs of utilities and maintenance works. For example, as we apply some concrete blocks as modal filters to protect residential areas from High Road changes, we could have the utilities on the High Road undertaking diversions and upgrades which would take out capacity and so give people the chance to get used to it. At the same time, we implement bus service changes, loading reforms and so on.

Yes, it means more time and planning up front and potentially longer "on site" disruption, but everyone knows the plan and they know the end game. What we can perhaps avoid is putting in a large expensive scheme and then having to go back and retrofit it or the surrounding area to deal with issues which were, in truth, foreseeable.


  1. I live in Chiswick *and* in one of the streets proposed for filtering because of rat-running so I've been up to my eyeballs with CS9 for the last few months.

    What you say all seems very sensible however to me, a difficulty seems to be prioritisation between different modes of motor transport. Chiswick High Rd now doesn't have bus lanes in both directions for the entire length of the street.

    TfL modelling predicts increased journey times for some journeys and opponents of the schemes use "won't anyone think of the buses" as an objection. In some cases this may be genuine but I think a lot are just using buses as a proxy for their car journey and what they really mean is "I will be delayed".

    Of course, any increase in journey time gets translated into a "it will cause pollution"" objection.

    Even if there was a bigger picture plan, I'm not sure it would make the process much easier. Filtering to block through traffic will still mean complaints from residents who no longer have that easy route out. Residents who don't suffer from parking problems won't want to pay for a CPZ even if it is highly likely an adjacent scheme will push traffic onto their streets. Lots will object to a PCZ until they actually experience inconvenience parking.

    1. And that's the rub - objections because people think it will be an issue (CS9) people objecting because they don't have an issue (CPZ). At least with a grand plan, the issues will have been thought about in the round and people can see where it is heading. I wonder how other cities and towns have managed it?

    2. Yes, I can see the advantages of a grand plan with a set of policies, such as:
      - non-residents should not be parking in a residential area therefore the policy is CPZ above a defined threshold
      - through traffic should be using defined arterial roads, not residential streets, therefore the policy is filtering residential streets above a defined threshold

  2. Couple of points:
    1. A precis of this blogpost would make a useful (even a necessary) preamble to your modal filtering guide. Apologies if I missed seeing this when I read the guide but I recall thinking this a lot when reading it.
    2. I don't believe anybody can make a *genuine* argument for allowing through traffic on residential streets. Everybody wants to live on a quiet, safe street with minimal motor vehicle traffic. Those who argue for allowing through traffic on other people's residential streets are just being callous and unfair to the people who live on these streets. Hence it is critical to have a monofunctional classification policy like the Dutch have for their road transport network, where there are only three road types and the function of residential streets is liveability for the residents, not transport capacity. As residents will always constitute close to 100% of an area where change to an arterial road corridor is proposed, this policy would eliminate the chance of inevitable arguing over removal of through traffic from residential streets. It won't guarantee democratic success for the arterial road proposal in itself but at least the arguments for the proposal will have to be made by and large on its own pros and cons, without the emotional heat about which residents will lose out or continue to lose out due to through traffic.

    1. Thanks Jim - I'll add the suggestion to my drafts folder for the second edition!

      From what I read, even the Dutch get opposition to schemes (funny that with them being people).

      My gut feeling (yes anecdote) is there will be a hard core minority who want to drive no matter what, so don't waste too much energy on them; convince the waverers that it might be a bit of a long way round when you drive, but your road will be quiet; plus you might actually enjoy making those short trips by foot/ bike.

  3. Also useful to have a global strategy and set of goals that supports your hierarchy - for example, if you want to prioritise walking & cycling, you might need to start charging people to drive to reduce the road space needed for motorised transport without increasing congestion, you might need to plan a wide inclusive cycle network so those people who've found it more exepensive to drive have an opportunity to shift modes safely, etc etc. This is where, so far, Khan and Shawcross are failing.