LCDS - Chapter 3, Cycle Lanes and Tracks

On Monday evening, from 8pm, the Embassy is going to be hosting a session discussing the new draft London Cycling Design Standards (LCDS), on Twitter (hashtag #LCDSHour). Katja Leyendecker has already provided an overview of the early chapters of LCDS, and in anticipation of Monday I'm going to give some initial thoughts on Chapter 3 - Cycle Lanes and Tracks, which covers cycle provision on links.

My immediate impression is that there is some good stuff in this chapter, but unfortunately it is quite woolly on what kind of provision should be applied under particular conditions, and there are a few strange recommendations that don't really correspond with best practice.

The good. 

The Cycling level of Service (p.59) is a good approach, based it seems on the CROW manual  characteristics of safety, directness, comfort and attractiveness. There are useful examples of how these criteria should be met, and how they might be failed. However, in what appears to be a nod to light segregation, 'adaptability' is added as a characteristic, which seems strangely irrelevant - 'adaptability' is not important to me when I am cycling along a road or a street. All I want is for the cycle provision to be good; 'adaptability' has no bearing on the level of service I perceive. There is a place for adaptability to be considered; it just shouldn't be here.

There's nice language about the importance of inclusivity, and of catering for anyone who wants to ride a bike. 

The intention in London is to provide for all types of cyclist. Assumptions may be made about how much space cyclists need, what can be provided to make them feel safer and how they behave under certain circumstances, but it is important to consider those who do not fit the stereotypes.

... followed by dimensions for non-standard bicycles, and the importance of avoiding barriers, and so on.

Effective width is covered clearly, with recommendations about how to maximise it, through the use of forgiving kerbing.

There's also a clear statement on how cycle tracks can be designed properly at junctions in paragraph 3.5.11 -

maintain the track at the same level by use of a raised table and apply corner radii that are as tight as possible. The side road should be required to give way to the track at the table... 

Continuous footway / cycleway treatments could also be applied to reinforce the visual priority in this case  

Followed by a useful discussion on how to minimise, reduce, or even avoid entirely conflicts at these junctions -

Where a cycle track is being considered but there are a significant number of side roads, it may be feasible for some of them to be closed or converted to one-way operation by point closure thereby enabling a track to be provided with fewer interruptions 

Equally, on the subject of making roads one-way, there is good stuff here on how to create more space for cycle provision by converting roads to one-way for motor traffic, with a good series of visualisations on how to achieve this. And two-way cycling on one-way streets is covered nicely - this really should be standard practice now.

But unfortunately these good recommendations - of which there are many - are rather lost in a long chapter which contains an awful lot of things that shouldn't really be in a design manual at all, at least not without explicitly clarifying that they are interim measures, or that they should only be tolerated under limited circumstances. 

More discussion of these problems below, but perhaps the most troubling general issue is the way this guidance explicitly abandons a matrix-based approach to cycling provision - one that suggests what should be appropriate, given the volume and speed of motor traffic on a particular road or street.

Instead there is a rather woolly 'place and movement' approach that makes vague suggestions based on the place or movement characteristic of the road/street in question. 

This runs counter to the way the Dutch design for cycling - explicitly matrix-based - as well as London Cycling Campaign policy recommendations. It opens the door to cycling provision being substandard on busy roads that are deemed to have more of a 'place' function. Motor traffic speed and volume would provide a more objective standard of whether a road or street is a genuine place, but objectivity appears to be replaced by more subjective guidance, which is worrying.

To take just a couple of examples of how this approach might not work, from this chapter itself. It states that dedicated cycle lanes

should not generally be used for streets with volumes above 500 motor vehicles per peak hour without a 20mph limit'

which is fine, but with a 20mph limit in place, how much motor traffic can be tolerated with simple cycle lanes? There is no answer in this chapter. A matrix would provide much-needed clarity.

Likewise, while the chapter is generally good on cycle streets, with guidance on how they should employed appropriately, it argues that they should be used only

where motor traffic volumes and speeds are already very low 

But how low? Again, no clear answer - this is all too subjective.

More generally, throughout the chapter, substandard provision is included, without comment. There is a long section on the apparent advantages of bus lanes - true as far as it goes - but no statement that they are not truly suitable as cycling provision, and appropriate only as an interim measure. 

There's a statement that shared use footways should have a maximum design speed of 10mph - no assessment of whether the kind of provision that necessitates this low design speed should even be contemplated in the first place. 

Light segregation - along with mandatory cycle lanes - are correctly identified as cheap and easy ways of transitioning  to more permanent measures. However there is an implication that light segregation has benefits of a more permanent kind, by not 'constraining' cyclists in the way that physical segregation does. Well, if people are being 'constrained', that suggests the provision (be it 'light' or 'hard') is inappropriately narrow - employing light segregation should not be a way of ducking these issues. (There are also curiosities - why should armadillos be placed on the inside of cycle lane markings? Why is it true that light segregation makes it easier for pedestrians to cross the road than properly-designed cycle tracks, with forgiving kerbing?)

Junction priority also provokes some worrying suggestions, particularly this statement that cycle tracks  

must be broken and converted into [cycle] lanes at priority junctions in order to reintegrate cyclists briefly with general traffic, enhancing their visibility.

This 'must' is directly contradicted by the recommendation in paragraph 3.5.11 quoted earlier (which comes just a page later in the LCDS!) which suggests cycle tracks can be continued through junctions. Indeed, maintaining a cycle track through a junction, at a raised level, with continuity, is both safer and more attractive than attempting 'reintegration', which is not employed by the Dutch, or by the successful Old Shoreham Road scheme in Brighton, which maintains cycle track continuity. Indeed, the LCDS chapter even curiously recommends bending in a cycle track, to the carriageway, in addition to the standard Dutch practice of bending the cycle track away from the carriageway at a junction, where space is available.

There is also a suggestion that - to achieve this 'reintegration', the physical protection must be broken some distance before the junction - 20m or more before the junction on roads with a 30mph limit - a recommendation which removes the ability to constrain turning vehicle speeds with tight geometry at the corner, and encourages left hooks (to say nothing of the attractiveness of 'reintregrating' with 30mph traffic). This is a design flaw with the current Superhighway 2 Extension. Physical protection should extend right up to the junction, to keep vehicle speeds low. 

Changing from 'lanes' to 'tracks' and back again means the height of a cycleway is constantly changing; not pleasant for cycling. A cycleway should be continuous, smooth and safe, and the physical design of the street should reduce or eliminate the danger of turning conflicts. It seems here that, instead, the quality, comfort and safety of the cycle provision is being sacrificed in an attempt to achieve the same objective. 

There is also something of a reliance on designing for the 'primary position'. If people have to adopt this position to keep themselves safe, then something is going wrong with the design of the street. For instance, on page 64, it is recommended that a primary position should be designed for, to deal with 'high left-turning flows'. Well, that should be dealt with properly, either through separating movements, or by reducing those high vehicle flows - the primary position shouldn't be endorsed as a compensating strategy. Likewise lane widths of below 3.2m - which necessitate the primary position - should not generally be recommended, except in low traffic areas. But this isn't clear from this chapter, which simply says avoid lane widths of 3.2-3.9m. 

My impression is that this Chapter of LCDS could be condensed, with poor, weak or subjective recommendations stripped out, leaving the good recommendations! That would be a considerable improvement, along with the retention of a matrix-based approach that I am not sure it is very wise to discard.


We'll have comments on Chapter 4 on Monday, as well as the discussion session in the evening.