The British Entrance Kerb - Ready To Ship

A very common design feature of Northern European streets is where footways and cycle tracks have their levels maintained across side streets. There are of course lots of different ways to do it, but the principles count.

The photograph below is a main road in Malmö, where there is a stone sett buffer area between the cycle track and the carriageway. The cycle track is "stepped" up from the carriageway and the stone setts are ramped as it passes the side street.

The detail varies (below), but the principles remain. The continuity of the walking and cycling space in terms of materials, levels and layout lend priority to those modes with drivers understanding that they are crossing someone else's space and the turn into or out of the side street is usually very tight for drivers.

The photograph below is from Billund, Denmark - the home of Lego. This example uses a little hedgerow as a buffer, but the continuous nature of the footway and cycle track is absolutely clear at this access.

Here's another example from Ettelbruck, a town in Luxembourg. Again, we have the buffer, the footway kept in the same material and at the same level across the side street and the ramped access. The turn is also nice and tight.

These are all nice and pretty obscure examples to demonstrate how common this is, but it is of course no surprise that the Dutch have taken this to the next level.

The photograph above was taken in Maastricht and you can see proper ramp units into the pedestrian street. In this case there is no buffer because everything is so narrow, but the levels on the rear part of the footway can be kept constant for the comfort of pedestrians. Having units doing the job rather than setts makes for a quicker installation and good uniformity of approach.

The photograph below is from Amsterdam showing great example of all of the little bits of detail working together to keep priority with those going ahead. In fact on this street, priority for those going ahead is set within the traffic laws, but actually the design does the work.

Here in the UK, we have struggled with these principles, but actually they have been here all along. Ignoring the cycle lane in the photograph below, we have a continuous footway with a buffer. The change in level is dealt with in the buffer area and the turn in and out is tight. Every so often you'll see nice little UK examples of this approach on social media.

The problem I find in the UK is that the principles are not well known among designers. In some places such as Waltham Forest (below), a conscious decision has been taken to roll out a consistent detail, although perhaps having to rely on paint to reinforce the layout isn't quite right.

As you will have guessed from the title of this post, I have just gone around the houses a bit. Of course, this is about showing you that we now have a real life version of the type of units the Dutch have been using for years with the first shipment about to head out into the wild from Charcon (part of Aggregate Industries).

The photograph above shows the left hand and right hand transition units with two ramp units set up in the centre. This is the version of the product which fits with British Standard half-battered pre-cast concrete kerbs (HB2 for the nerds). For lots more detail, have a look at this post from just over a year ago. The sketch below shows how the units (in pink) fit with the wider layout of a side street.

The interesting behind the scenes thing is the first units were going to be a square profile version in a stone effect finish for a scheme in Salford, but in fact, the first UK scheme to use them is the Coundon Cycleway in the UK's Motor City of Coventry where lots of standard materials are being used. It is also worth mentioning that the scheme is also using a 30° kerb between the cycle track and the footway. This is new cycleway will be a smorgasbord of design principles promising to be one of the best in the UK. Do follow Peter Howarth, the scheme's project manager, on Twitter to see photos of the scheme emerging and all credit to him for putting faith in the product.

This has been a bit of an obsession for me ever since I had my first chat with the technical people at Charcon around the concept and why it could help in delivering continuous side street treatments. I do need to give a hat tip to Catriona Swanson who got Salford City Council discussing the product with Charcon because it needed a decent sized project to make the development of the product viable from a research and development point of view. 

I also need to give a hat tip to Adam Tranter, the Bicycle Mayor of Coventry (among other things) who got me and Peter Howarth discussing the the units. What this has shown is once a few people see the value of a good idea, it can take a life of its own. Charcon tell me that they have had orders for the product from the Isle of Man and they are getting a steady stream of enquiries from designers and specifiers. 

I can't wait to see the first units going in, even if it has to be from afar at the moment. At last 2021 sees another piece of the jigsaw becoming available to us. 

A Glimpse Of The Past

The footways are being reconstructed on my street and the work has offered a little glimpse of the past and serves to remind us a little of the effort that goes into the fabric of the streets that we rarely see.

Our street is around 90 years old and sadly the wonderful old concrete paving flags are giving way to asphalt. It's a maintenance-related decision because asphalt is seen as easier to maintain than flags. That may be true to a certain extent and the new surface will be far better for many, but I like the warmer look of old fashioned flags. Anyway, that's besides the point for this post.

The photograph above is the excavated footway. you can seen the thin asphalt layer of the carriageway (about 50mm) over a lightish brown layer. This lower layer is an old-fashioned road-building material know as "hoggin" or "as-dug" (and there will be all sorts of regional names). It's a naturally occurring mixture of sand, gravel and clay which is just the right consistency for compacting into a good, solid base for a carriageway or footway.

The photograph above is a closer view. The material is a little lighter here because I took the photograph a couple of hours after the other one and the hoggin has dried out a little. Against the scale square, you can see the varying size of stones going from around 30mm-40mm in size down to the tiny particles of sand and clay. The stones are quite rounded which shows that they have been subject to the action of water at some time in the past.

The reason why this material compacts so well is that the graded sizes of stones and sand provide a tight "matrix" with the clay particles acting as a "filler" for the tiny gaps which are left. Hoggin can be compacted to a very smooth and impermeable surface and if profiled properly with decent drainage, this can be a perfectly serviceable material for paths. The problem comes when you try to run wheeled traffic on it because it starts to degrade the surface allowing water to get into the material and left unchecked, it will rut and fail.

The old-fashioned solution to this problem was by the use of "tar and chips". The old roadworkers would complete the carriageway from hoggin and then the surface would be coated with a tar-based bitumen and then stone chippings spread, maybe with a couple of layers. The tar used was a byproduct from the production of "town gas"; gas which was produced from coal. Tar is carcinogenic and so it's use in roads is another legacy of industrialisation.

This means that the hoggin was protected from wheels and rain. If potholes formed, then they were easily repaired and a new surface could be laid over the top. There is a modern parallel with surface dressing and microsurfacing, two techniques which are able to seal an old surface and add a little bit of resistance to rutting as well has having anti-skid properties.

My street doesn't have a tar and chips surface, it is relatively modern (although at least 30 years old I would guess). Any old surface has long since been replaced, but the overall construction is pretty simple. We don;t get heavy lorries on our street and so the thickness of asphalt is appropriate. Main roads will be more heavily constructed (with thick asphalt layers), although running constant heavy traffic on a construction like our street will fail - an issue where side streets are being used for cut throughs.

In building the carriageway, the old roadworkers will have relied on muscle a lot more than today, but there still would have been heavy rollers to help with the compaction - maybe even steam-powered. Today, roadworkers will have a little more help with grab-lorries, mini-excavators and a whole range of compactors from the whacker-plate type up to vibrating dead-weight rollers depending on the job.

The photograph above shows the footway after the slabs had been removed along with their bedding layer of sand. The old hoggin is still evident across most of the area, but the greyish and pinkish strips on the right are modern. The greyish material will be crushed limestone sub base and the pinkish will be crushed granite sub base. This is where utility works have taken place and rather than carefully setting the hoggin to one side for reuse, it was tipped away and replaced with more modern materials.

The photograph above shows the next stage of the work. New kerbs have been laid and thankfully the verges are being retained (although the soil is going to need to be cleared of kerbing concrete). The grey area is additional limestone sub base to fill up the space which used to be concrete for a dropped kerb to a driveway. This hasn't been compacted yet and so we get a good look at the different stone sizes. Like the hoggin, we have a range of stone sizes. In the case of the modern specification this will be large stones up to 75mm in size down to dust to fill the gap in the matrix.

The next stage will be to lay the asphalt. The hoggin and limestone will be compacted to a tight finish and then two layers of asphalt will be laid. First a 50mm thick layer with a maximum stone side of 20mm (known as a the binder course) and then a final 20mm thick layer with a maximum stone size of 6mm (known as the surface course).

The photograph above is the binder course and the photograph below is the surface course.

So there we are, a glimpse into a little bit of mundane road building history. Once the work is finished, we'll soon forget about it and go back to taking a nice new walking surface for granted until the next time someone digs it up!

It's 'A' Sin

I detest outdoor advertising. At best it's an ugly addition to the street scene and at worst, it makes it harder to walk along the street given that it adds zero utility.

One of the most ubiquitous pieces of outdoor advertising is the advertisement board, also known as the "A-board". In bygone days, you may have seen the odd one tucked outside a greengrocer displaying prices, but these days it seems that every shop and business operator feels the need to have one in the arms race to entice customers into their premises (Covid-19 notwithstanding).

In many circumstances, the use of A-boards significantly restrict the ability of people flow along a footway and in some cases, they can physically prevent some people from passing where the footway is narrow. For visually impaired people, A-boards create unexpected and unpredictable hazards which have the potential to cause a fall.

This A-board narrows the space between the

bench and the shop front.

To business operators and the public alike, the rules are not straight-forward, inconsistently applied and so it's no small wonder that streets get strewn with the things. I've often had it explained to me that A-boards are part of the vibrancy of places and that they show people that businesses are open. I've been told that they're needed to help direct people to tucked away businesses and criticising their use is anti-business. Well, I don't care. The ability for people to move safely and easily in an uncluttered environment trumps any of those "benefits".

From a legal point of view, A-boards are covered by provisions of the Highways Act 1980 (England & Wales). S130 is a general duty for the highway authority to protect public rights, including preventing obstruction. S137 sets a penalty for wilful obstruction of the highway - level 3 on the "standard scale", a reference to the Criminal Justice Act 1982 (£1,000) which can be imposed by a magistrate's court. S148 sets the same penalty for depositing things on a highway.

The seating space isn't taken from walking space,

but the poorly place A-board does.

S143 of the Highways Act 1980 gives powers to highway authorities to remove obstructions and S149 gives powers to remove things deposited on the highway. Scotland has its own powers under the Roads (Scotland) Act 1984, but I'm afraid I am not as conversant with these as I am the Highways Act. There are also provisions for licencing of things on the highway using S115E of the Highways Act which is a bit of a catch-all, but generally used for giving permission to miscellaneous "things" on the highway owned by third parties.

There is also planning legislation to contend with. In England, there is The Control of  Town and Country Planning (Control of Advertisements) (England) Regulations 2007 with other variations in the other administrations. The effect is, however, to generally exclude A-boards from planning law, so long as they are placed on the owner's land or with permission from the owner (including the highway authority). More guidance on this is available here. In some cases, a shop's forecourt could have accrued highway rights through public use further complicating the issue.

An A-board arms-race. Adverts jockying to grab

the attention of passers by sterilising a whole area

of footway.

In terms of managing the issue, there are a range of approached. For example, Edinburgh City Council has a complete ban on A-boards (apart from some specific situations). This isn't actually a ban per se, because placing things on the highway is already banned in law, it is just that Edinburgh has put into place a policy that it won't grant a licence for them. The London Borough of Hackney has gone even further and has a complete ban without exception. I like this approach because there are no arguments.

Other authorities have policies of tolerance so long as business owners follow general rules (positioning, carrying public liability insurance etc). I'm not entirely sure this is the right way to do it because no lawful ability for people to put A-boards out in the first place and in the absence of a licence with each owner, this is a policy of ignoring the issue. Authorities such as Hertfordshire and the London Borough of Havering operate this way, but with differing guidance. 

The footway on the left is pretty much blocked.

Many other authorities operate on a licence application whereby the owner must submit an application (with varying levels of detail) which will be assessed to reach a decision. A licence will be charged for on an annual (or longer) basis with the fee covering the administration and presumably a level of enforcement to ensure licenced A-boards accord with their licence conditions and non-licenced A-boards are removed. 

What is generally common is that where an A-board is in contravention of the local policy or a licence, it will be removed with a release fee charged. This is because having to go through the magistrates court process to have a fine issued is costly and time-consuming.

It's not just the A-boards, the streets are under pressure

for seating as well as containing "official" clutter.

So what? There's lots of clutter out there, so surely a few A-boards isn't the real problem here? That's true to some extent. There is lots of pressure on street space, whether it's "official" clutter coming from lighting columns, traffic signs and all of the other stuff; outdoor seating for pubs and cafes; and other things like telephone kiosks, telecoms cabinets and phone masts. However, other things being done badly is no excuse to make things worse.

My general approach has always been that things in the street should earn their right to be there and things which perform more than one function are even better. There are things we need to for basic utility such as providing lighting and having some traffic signs - of course these should be well designed. We might want to encourage outdoor cafe culture and that is fine if again, it is well designed and there is space which means that we should be rejected the poorly thought out. A-boards do not perform a useful function for the street or its users and so well done to the authorities which have banned the rotten things (or who won't licence them by policy if I'm being accurate!)

Cargocycles Can Tame Suburbia

I have different ideas for blog posts listed - some I have even started. I've just done a tidy up and found a post I had started to write back in July 2017.

I had got as far as writing the following;

As I piloted our cargotrike around central London on the Ride London Freecycle a couple of weeks ago a chap drew next to be and asked about it.

It's a Christiania and it caught the chap's eye as he was Danish (Denmark being home of the Christiania trike) and he was surprised to see one in London. He asked if we had hired it for the day, but when I said it was ours, he further wondered if it was our second car which was very perceptive! He himself had recently got rid of his second car as his heavy lifting was done on his Bullitt, another Danish classic.

Cargocycles are a common sight in Copenhagen.

I don't recall why I stopped writing the post, but it's an interesting thing to come back to. My revisited fleeting chat with the Dane sparks a conversation in which both highway and spatial planning come together in shaping how people travel and the tools they have available. It also prompts thought about how policy (and therefore what gets built) shapes our environments, how we interact with them (and each other) and who we prioritise. Of course, it also has me thinking about how cargocycles can be instrumental in changing our urban fabric.

Even larger cargocycles operate at a human scale

At a basic level, the experience of using a cargocycle in a typical Outer London borough is stark in contrast with using one in Central London (or maybe Waltham Forest). Decades of spatial planning for low density housing and a stratification of employment and commercial land immediately means that people have to travel and for some things they have to travel quite a long way. 

Cargocycles can replace light vans for deliveries

Outer London (as with many urban parts of the UK) has based decisions on significant numbers of households having access to private cars and from this flows the continuance of the same type of development and highway management which maintains the status quo. What is often missed is that where a household has access to a car, it is not available to all members of that household who are left to use whatever transport options remain.

Cargocycles can fill in the transport gap between

walking and driving, especially when something or

someone needs to be transported

The thing about cargocycles is that they can fill a transport gap where a distance to be traveled is a bit far to walk (either distance or time); where something (or someone) needs to be transported; and where the distance is easily cycleabe (and that distance increases with e-assist). For example, the suburban task of doing a food shop often means having to go to a large supermarket which is a product of spatial planning policy with highway connectivity which facilitates access to such by car. 

Cargocycles are the ultimate door to door shifters

of stuff because they can go where motor vehicles cannot

The large supermarket model also favours those who are able to purchase in bulk and so in terms of time efficiency, it makes sense to visit such a supermarket infrequently, but to do a large shop. Cargocycles can disrupt this model because they can deal with both the distance and the carrying issues created/ perpetuated by the model. That's not to ignore the problem with the centralisation of all sorts of services which by accident or design favour driving, but cargocycles create competition on this uneven playing field.

Cargocycles are great for shifting small children

and they take up way less space than cars

So what? Well, my fleeting Danish acquaintance got rid of his second car in favour of his cargocycle and he assumed I had done the same. In fact we have only ever had one car, but it is true that they cargocycle has replaced many car-based trips which are too far to walk, but easy enough to cycle and transport stuff. This is important because people dropping cars in favour of cargocycles are reducing car parking demand (at home or at destinations) and freeing up highway capacity.

A shift in development density could make store

deliveries by cargocycles commonplace

Of course, most people are worried about the safety of cycling with traffic and cargocycles will seem quite alien to many, let alone being able to imagine how they would use one (secure parking and storage is a significant barrier for example). This means that we are back with the chicken and egg problem of needing to build a decent cycling networks to enable people to switch to cycles in the first place, but places serious about being progressive will be doing this anyway.

Enabling cycling makes it easy to choose a cargocycle

As time goes on, there will surely be a critical mass of cargocycle users (including commercial users) which will further erode the need to run so many private vehicles and space can be given over to cycling (and by extension walking). This has implications for spatial planning and highway policy because it nips at the heels of the model of large supermarkets, urban retail parks, drive-through restaurants and the like. 

There is always a cargocycle for the job

Developers are not fools, they look at future trends, especially those who run pension funds and other investments. Sitting on a large low density commercial/ retail site starts to look like a long term risk where the transport mix starts to shift and so thoughts will turn to higher density mixed-use sites. The challenge can be that sites such as this have been serving private cars for so long, there has never been any investment in public transport and so it is clear that cycling is going to be a vital part of many people living and working on such sites in the future. In fact, could today's retail parks be tomorrow's local or district centres.

Cargocycles: for the win

Cargocycles are the pioneer species of the humanisation of suburbia. They can help terraform low density development and provide a genuine bridge between needing a car for some tasks and a reduction in suburban car ownership. 

The Great Stink Redux

One of my civil engineering heroes is Sir Joseph Bazalgette, probably most famous for leading the construction of major sewers in Central London as a response to a spiraling public health crisis coming from cholera.

Back in the mid-1800s, the established medical thinking was that cholera was spread by a miasma (foul smell) from polluted water. The main problem London had at the time was raw sewage was being dumped in rivers and watercourses from which drinking water was taken (there was no treatment as such). It took people like epidemiologist, John Snow, to make the link between rotten water and infection, although it wasn't until later that century that germ theory was established and overturned miasma theory.

Bazalgette was only permitted to proceed with the plan to intercept the sewers of Central London before they discharged into the Thames when the Great Stink of 1858 made conditions from the Thames so bad that it affected the sitting of Parliament. It was all lots of things happening at once, but the dealing with the sewage in the Thames had the medical theories playing catch-up to some extent.

For a civil engineer who often finds politics frustrating, the Great Stink is a great example of having to deal with professional inertia and political will in order to deal with a public health issue through developing infrastructure. It can be rightly argued that Bazalgette's work saved many lives, despite medicine not catching up for a while after and it has me thinking about parallels today.

I guess that Covid-19 springs to mind, but that is coincidental. I'm thinking of the way we have allowed our streets to be dominated by motor traffic. That we need lots of it for cities to function or be prosperous is analogous to the miasma theory - it's a long held belief within much of the transport profession as well as the wider public and therefore politicians. Like cholera, it's impacts can affect anyone, but more likely those living in poorer neighbourhoods. There is political resistance to change the infrastructure because of concerns that it won't work or that it challenges the status quo.

Of course, many have embraced the new germ theory that in fact we have to change how things operate, that it does work and that we can't afford not to do it. Are Low Traffic Neighbourhoods the modern equivalent of John Snow removing the handle from the Broad Street water pump - something we have found to be successful through experimentation (and epidemiology comes into it) before the accepted theories have changed?

Let's make no mistake. Streets are part of our living space and although Covid-19 has thrown that into stark relief, the Great Stink has been with us for well over 60 or 70 years. Rather than clean up our act, we have defecated into our drinking water and then wondered why we have road danger, sprawl and air pollution. We need to treat our streets as a public health emergency which requires both radical adjustments to how they operate along with structural change to how we design and manage them. Maybe we also need to make it personal with politicians - let them breathe the Great Stink of the 21st Century.