Saturday, 10 April 2021

#LDNCycleSafari Goes Solo: A Trip To Thamesmead - Part 1

In the late 1990s/ early 2000s, I worked in Thamesmead, Southeast London. It is the place where I was exposed to all sorts of interesting construction. It is also the place where I worked on a project which helped me become a chartered civil engineer, so I will always have fond memories of the place.

I haven't been back since 2004, but on a chilly Good Friday, I made a pilgrimage back to Thamesmead to see what has changed in the intervening years as well as what was as I remembered it. In this week's post, I will be looking at some of the old and in next week's, I shall be looking at some of the new.

Thamesmead straddles the modern London boroughs of Greenwhich and Bexley, but there is a long history of human activity in the area. For a few hundred years, it was part of the Royal Arsenal which was established on the Plumstead and Erith marshes.

My stint in the area was working for Thamesmead Town Ltd, a company set up by the London Residuary Body which was responsible for the disposal of the assets of the Greater London Council (GLC) which fell victim to being abolished by the Conservative Prime Minister, Margaret Thatcher. I'll explain some of the engineering as I go on, but looking back I really do think that the loss of the GLC was a huge loss for London and the UK as a whole in terms of innovation. But that's a story in its own right.

Thamesmead is probably most famous for the GLC-era development of what was essentially a new town - The Town of Tomorrow. It was meant to be a modern development of high density housing, schools, communitry facilities, open spaces, water and everything else people needed. The development welcomed its first residents in 1968 and at the time, people were vetted to make sure they would be able to afford to live there (it was going to be quite exclusive). 

Changes in social housing policy and approach meant that the original vision was short lived and the new development became what was known as a "sink estate"; a pretty derogatory euphemism for a place and its people gradually starved of investment of both financially and socially. The original part of the development is also infamous as providing the backdrop to some of the scenes in Stanley Kubrick's disturbing dystopic 1971 film "Clockwork Orange"; itself based on Anthony Burgess's 1962 novel. In many ways, this was a watershed moment for this short-lived Utopian vision for a new town in London.

The photograph above is Southmere Lake. One of the scenes from A Clockwork Orange was filmed beyond the Lakeside building with the orange hoarding at Binsey Walk. The lake and Lakeside building were also the backdrop for the 2009 - 2013 TV show, Misfits. Everything here is now boarded up and being redeveloped. 

Thamesmead has probably got examples of housing from each decade after the 1960s and 70s. My turn of the 21st Century experience there saw a mixture of houses and flats being built, but Thamesmead Town was there to facilitate development by remediating industrial land and building core infrastructure including roads, sewers and canals. The old Royal Arsenal lands are contaminated with all sorts of nasty chemicals from explosives manufacture and ancillary services, including the wonderfully named "Blue Billy", a byproduct of gasworks. 

One of the key pieces of work I was involved with was ground remediation which was the removal of the top layer of contaminated soil and replacement with a water-permeable membrane and clean sand. One of my schemes was Meadowford Close where I oversaw the remediation process and one one occasion ended up getting the Metropolitan Police bomb squad out to check something we dug up. It turned out to be old Royal Arsenal ordnance, but inactive thank goodness! In fact, most of the nasty stuff dug up on the site were home-grown weapons of mass destruction.

I also got involved with the completion of the new roads, footways and cycle tracks. There is some interesting walking and cycling networks in Thamesmead which reflect their eras, but sadly they haven't really reached their potential. I also got involved in building sections of canal. Thamesmead is built on reclaimed marsh which is protected by a river wall, itself being part of the London flood defence system of which the Thames Barrier is part.

The photograph above was taken in May 2000 of the walking and cycling bridge between Delisle Road and New Acres Road over one of the newer sections of canal in the area south of Gallions Reach Park which was originally called Gallions Reach Urban Village. There's a spine cycleway along here, which unfortunately ends at Barnham Drive (as seen today, below) which should have continued east through the site of the Thames Gateway Bridge to connect up with routes to Thamesmead Town Centre (I'll come back to this later).

The town has a canal system which links a series of large lakes. As well as providing amenity (including sports on the lakes), open space and ecology, the system is vital for fluvial flood prevention - in other words, it's not the Thames which is the main issue, its the water coming from the upstream catchments. 

The water level in the lakes and canals are at the same level as the general groundwater and in a flood event, the levels rise and it's that rise over the whole area of the water courses which provide flood storage. The canals are only 610mm deep (2 feet) and so easy to walk through (although I seem to remember that Southmere Lake is twice that depth for boating - I can't remember the details of the others). Obviously the hydrology isn't without complexity, but the storage above the general water level does mean water seeps into the ground beyond, but far slower than it being pumped out.

From memory, the original GLC design for the system was for a 1 in 205 year storm event which was well ahead of its time with roots in work Bilham did in the 1930s. I can't quite remember which year, but there was some extensive flooding around Plumstead when I worked in the area with Thamesmead having the odd canal path with some puddling - that's how good the system is.

The original canals had concrete walls and bases (although not watertight). More recently (well, 20 years ago), the canal system was still engineered, but this time in a more naturalistic way. The photograph above from August 2002 was taken from the southern tump of the "Twin Tumps" canal looking out to what is now Waterside Close - you can see the very shallow shelf for marginal plants. A tump is a little hill and in the case of the Twin Tumps, they are old Royal Arsenal structures each of two C-shaped earth bunds with the smaller 'c' back to front overlapping the larger 'C'. This arrangement was for sending explosions from stored ordance up rather than out.

Depending on the tides in the Thames, water is either stored in the Thamesmead system or discharged into into the river via suices or pumps. Lake 4 Pumping Station is shown in the photograph below and uses 4 Archimedes screw pumps. Recently upgraded, it can apparently shift 2.4 tonnes of water a second!

The original parts of the development also had habitable rooms from first floor level and some of the more contemporary developments had townhouses without living accommodation at ground floor (just garages and utility rooms). This was a second line of defence from flooding. The original parts of the development also had above ground walkways connecting buildings and blocks away from traffic which perhaps added to some of the social and security issues which blighted the estate.

Thamesmead has a network of large dual carriageways which looking back are completely over-capacity and create severance issues. There have been some alterations with bus lanes and surface level crossings, but they both remain a barrier and make it easy to drive around the area. They are part of a wider and incomplete network of roads. 

For example, the Thames Gateway Bridge (a revised and descoped version of the originally planned East London River Crossing - ELRiC) was part of earlier plans for network of motorway-style roads across and around London with a link connecting the A406 North Circular, south to the A2, but the work never got beyond Thamesmead. 

Where the walkways were built for the original parts of the development, slightly later phases carried on with grade separation, but with walking and cycling being taken under the roads, often next to the canals.

The photograph above is on the edge of the town centre, taking walking, cycling and a canal under Central Way. You can see the stepped arrangement keeping walking and cycling separate and the view through the underpass. The wall to the left of the footway in the photograph below is a sealed section of canal wall because the route is lower than the water level in the canal. This arrangement really has a Dutch feel to it.

On the other side of the underpass, the design changes to something more 80s where the footway and cycle track end up at the same level (below). The 80s to 00s saw development of the walking and cycling network like this. The earlier sections simply have a different surface (block paving for walking, green asphalt for cycling) with later sections having a tactile block between the two. 

What I think has happened is the underpasses were built with the original main roads with connections made as development progressed through the years. Unfortunately, the original vision seems to have been lost going forward.

A bit further south along this route is Hutchins Road where there's a typical shared area junction for walking and cycling (above), but it also hints that the walking and cycling networks do operate independently of the driving network as the left and right options here go through areas that cars cannot.

The local cycling network could do with some investment be quite a lot of it is both showing its age and also that separated infrastructure does last a very long time and is not hammered by constant traffic. From the Hutchins Road junction, I chose to turn left to head east which takes one through an area of open space. There is a wide section of shared use, but then the separate and stepped infrastructure returns with a bridge over a canal and an underpass beneath Bentham Road

This underpass (above) also has a the canal running under, but the walking and cycling route is above water level. Bentham Road in this case is taken over the bridge on a long hump which means the vehicles make the effort not the people walking and cycling. Because the bridge is piled, the carriageway either side is susceptible to settlement and 20 years ago there was work to reconstruct the approaches.

A little further on and we reach a junction outside Hawksmoor School. However, this is no ordinary junction because it is a cycle track junction with adjacent stepped footways (below).

It's a wonderful thing to see - a wonderfully safe environment from which to access the school, although the paths will feel lonely at some times of the day and night not helped by the housing to the west of the school facing away from the walking and cycling network.

A little further west and there is at least a sports court to entice some activity and the route carries on following the canal (which eventually links to Southmere Lake. A little further on and the route becomes shared as is passes in front of a local shopping parade at Claridge Way (below).

From here, I threaded my way onto some local streets which isn't always easy because the wayfinding fails a bit. I was looking to head south towards Southmere Lake, but that requires crossing the Southern Outfall Sewer which crosses the area from west to east in an embankment which also carries a greenway known as the Ridgeway. Eventually I worked out that I needed to access Poplar Place and a shared path beyond - the access wasn't clear because of a recent bit of redevelopment which could have treated the path far better rather.

I was aiming for the junction of Eastern Way and Carlyle Road, a huge and over-engineered grade separated junction through which a shared path runs to connect wth the Ridgeway and the earliest part of the Thamesmead development to the south of the Southern Outfall Sewer. This route through the junction is an incredibly lonely place to be because it is so tucked away from housing. Threading my way up and south took me to a bridge crossing Eastern Way, but at a lower level than the junction. It's an impressive piece of period architecture and engineering from the early 1970s.

This sort of brings me full circle as I started talking about the earliest part of Thamesmead built around Southmere Lake and I'm nearly back there with the walking and cycling route. This part of the journey will continue in another post, but now I want to head back over to the newer parts of the development to the west of the town centre.

The Thames Gateway Bridge project saw a corridor of land reserved for the construction and operation of the project to the west of Thamesmead town centre. Once complete, the long term plan included the connection of the canal and road system from the western part of the town centre to the town centre itself with the area under the bridge becoming part of a local open space. The bridge was cancelled by Mayor Johnson in 2008 and so it simply isn't clear what will happen to this piece of land.

The photograph above was taken from the top of Gallions Hill, a constructed landmark feature of Gallions Reach Park. The wooded area just beyond the more formal park contains the Tripcock Wetlands, a project I led the design on and which I used as part of my chartership submission. This project uses bioremediation to treat waste water from an adjacent engineered land fill site used to contain contaminated soils arising from the wider development, thus reducing the need to shift materials. I put out a thread on this project on Twitter

Anyhow, it is over this undevelopable area that the bridge was meant to rise from around the Western Way/ Central Way junction (below) to connect with a junction at Royal Docks Road on the north side. The yellow lines on the image below show the approximately extent of an originally planned toll plaza. Had the bridge been built, then I guess technology would have rendered the plaza obsolete.

Curiously, part of the junction on the north side has been built. There is a southbound slip road from the A1020 Royal Docks Road which has an odd stub looking towards the southern side of the Thames (below).

The slip road is then carried over the A1020 on a bridge which is way too wide for a one-way slip road (below). This is where the Thames Gateway Bridge would have ended, but it now leaves a curious piece of 20th Century urban infrastructure.

What this all means is that the western side of Thamesmead out to the Royal Arsenal neighbourhood is now pretty cut off from the town centre. Driving is easy along Western Way and Central Way, but walking and cycling only really have the river path which is now part of Quietway 14. In fact, in order to access the town centre, one must travel east beyond the town centre itself and then circle back via Linton Mead and Central Way. 

The photograph above is part of Quietway 14 along the Thames, recently upgraded - it used to have a long gravel section around Tripcock Point. The route is a trip through history with sections of an earlier vintage (below). In fact, this is all part of a the Thames flood defences - some were made accessible when built and some have been open up in more recent years.

The stub of Barnham Drive I mentioned earlier has a doppleganger on the other side of the Thames Gateway Bridge Corridor at, well, Barnham Drive. In fact, in connecting up, there would also be a walking and cycling spur to Newmarsh Road which already provides a quiet and mainly traffic-free route out to the east - it would have been via another underpass at Central Way, but unfortunately it has been buried in favour of a toucan crossing. Getting this underpass back into use and connecting up the route was another project I worked on, including the link to Pitfield Crescent.

The photograph above is the Central Way underpass in June 2000, shortly after we opened it up and had the water pumped out.

So, we're back again to the west of the town centre and the Gallions Reach Urban Village part of Thamesmead. There are walking and cycling routes running along the canal (below) between the stub of Barnham Drive and the river in the east (connecting to Q14) at Princess Alice Way.

One final curiosity this week is the roundabout junction of Merbury Road/ Warepoint Drive/ Miles Drive in the heart of the Gallions Reach Urban Village part of the development. Warepoint Drive and one arm of Merbury Road have cycle tracks. They are only on one side, it's not clear that that are two-way and to be honest, the roads are pretty quiet (below).

Where they meet the roundabout, an annular cycle track is provided and when you cycle, you're kind of led to go around clockwise. For the eastbound direction from Warepoint drive, this means you end up crossing 3 arms of the roundabout to continue on Merbury Road where crossing one arm and going anti-clockwise might make more sense (and I assume anyone who does cycle here regularly on the track does this).

The crossing points have small refuges (too small for most users), but we have a compact roundabout with an annular cycle track and tight geometry for traffic. Like lots of place around Thamesmead, if you half close your eyes on a sunny day, you can almost see the Dutch design principles!

I shall leave you this week with a video of my ride around Thamesmead.

Saturday, 3 April 2021

Kerb Your Enthusiasm: Flush

The other day, I posted a photo of a dropped kerb at a brand new toucan crossing which had been left sticking up about 25mm above the road surface. I thought it was obviously poor, but some disagreed.

Having a flush dropped kerb at crossing points really shouldn't be a point for debate and frankly, it's not. If you disagree with flush kerbs then you are purely and simply wrong.

The photograph above shows the offending kerb and before I talk about why kerbs should be flush in these situations, it's worth exploring a couple of other points. Notwithstanding drawings and scheme specifications, the actual type of kerbs we have available make kerb upstands more likely simply because the units are not designed to be laid flush.

Many British Standard kerbs are designed for road only applications and a general approach is to lay them with a nominal 125mm upstand. The image above shows a HB2 standard half battered kerb laid with a 125mm upstand and a BN3 bull-nosed dropped kerb. Half battered means the top part of the kerb is angled back from vertical and bull-nosed means the traffic-facing corner is rounded. Between the two is a transition kerb.

To get the dropped kerb laid flush with this units, we either have to run with a general upstand of 100mm or cut slices out of the transition kerbs to be able to tilt them down to meet a flush bull-nosed kerb. The problem with a flush bull-nosed kerb is that it's hard to properly compact asphalt tightly up to it.

The sketch above is a representation of the stones within the asphalt at the interface with a bull-nosed kerb laid flush. The stones and other particles within the asphalt matrix to the right of the red line never compact properly and the result is they "fret" or gradually come loose through traffic and weather action and eventually potholes form.

These dropped kerbs are actually designed for vehicular traffic, not pedestrians. Many manufactures make kerb ranges which are all square edged which means it's easier to get the dropped kerbs right, but the British Standard kerbs remain the most common and with retrofit schemes, they are often the option which fits into existing kerb lines.

The other feature of the bull-nosed kerb is that the upstand can help direct water and this is often the reason designers give for not providing a flush kerb; so that the crossing point doesn't get flooded and in low temperatures, ice doesn't form.

The sketch above shows a bull-nosed kerb with water (in blue) as it would run past assuming a general gradient along the road. The upper image has an upstand and with 500mm of water running along the channel of the road, this is the "flooded" area which stays in the road. The lower image shows that water would go over the kerb and the bottom of the ramp. The width of water running along the road channel is a function of intensity, road gradient and road crossfall.

However, this is the situation during a downpour with water running along the road channel and so in both cases, if the rain is that heavy, pedestrians are still going to have to deal with water. A well-designed crossing will have involved the designer looking upstream (hydraulically speaking) to see what the drainage is like. Having a gully just upstream of the crossing will help reduce the amount of water passing the crossing point.

After a rainfall event, there might be some residual water sitting on the kerb, but this will drain away. In the round, I don't buy this argument because it is tenuous at best. I imagine that crossings with puddling problems will be more down to local surface irregularities and quality of installation rather than flush kerbs being a drainage problem on principle. Perhaps designers are double checking local levels properly because it's more staff time and therefore cost.

In the UK, we provide flush kerbs at crossing points to favour wheelchair users (electric, self-propelled and attendant propelled), mobility scooter users, people pushing prams and buggies; and indeed push scooters. The intention is to make the transition from footway to carriageway and back as smooth and easy as possible. It does then follow that we provide appropriate tactile paving to aid visually impaired people (more on that here).

If we are left with an upstand, it means that users with small wheels risk catching them which could end up with people people being tipped from their conveyance - a fair greater risk than the theoretical possibility of it being a bit wet.

The wheelchair in the photograph above has a small pair of wheels which can turn in all directions (like supermarket trolley wheels). If being self-propelled, the user may not be able to easily mount a dropped kerb with an upstand and if being pushed by an attendant, there is a risk that the person gets tipped out if those wheels get caught on a kerb.

The answer to this problem is to use square edged kerb systems which certainly fit with urban realm outcomes far better than the British Standard units. A nominal kerb face of 125mm can be high for people stepping up when crossing away from a formalised crossing point, although I should add that some advocates for visually impaired people would prefer the high kerbs for certainty in detectability.

The other option is to turn the bull-nosed kerb upside down as it has a square edged base (or use a square edged channel block). It requires a skilled roadworker to get this right, but there's no excuse. Some specifications (including guidance) suggests a tolerance of flush to +6mm which is fine, but in my experience, a skilled roadworker will be able to locally set out a dropped kerb to be flush.

If you look very closely at the photograph above, you will see that the flush dropped kerb has been formed with bull-nosed kerbs laid upside down. There is a very slight upstand on the right-hand end, but it is well within 6mm.

None of this stuff is particularly complication, but it does require good design, clear instruction and skill roadworkers to bring it all together for the right result. If you have upstands on crossings near you - demand better.

Thursday, 25 March 2021

#LDN Cycle Safari: Barking Riverside

As I continue to get my lockdown exercise within a sensible cycling round trip of home, my options are becoming somewhat exhausted. However, I realised there was a relatively new development I hadn't had a nose around and it was as good a reason as any to get out in the fresh air.

So, I wound my way through the hostile streets of Outer London (east) down to the A13 in search of something a little different at Barking Riverside. The area is part of the post industrial Thames Gateway which loosely covers both sides of the Thames from the edge of Central London out to the Thames Estuary. There have been a variety of development models and attempts to regenerate areas; the fortunes of which have ebbed and flowed with the tides.

The area covers the area roughly between the River Roding in the west and The Gores (another water course) to the east. It's hard to pin down exactly what is going on given the mish mash of old industrial land, existing businesses and housing which charts the areas history from marshes at the end of the 19th Century to modern times. The area continues to develop and redevelop with a new residential area under construction towards the eastern side of the site. 

My visit took me to the central area between River Road and Thames Road, a newer development bounded by industrial areas to the north and west, a declining industrial area to the south (flanking the Thames) and a part of the old Barking Power Station complex to the east. This phase of development is known as "Rivergate" on the site masterplan with other areas at different states of construction.

The photograph above was taken on Renwick Road showing a huge electricity transformer complex. The development I sought was behind this to the west. As you'll see on the video which goes with this post, Renwick Road is a very hostile place to cycle.

Renwick Road becomes River Road (forming a long loop which meets the A13 at each end). I turned right off Rover Road into Handley Page Road into one part of the more modern development.

The photograph above shows the Handley Page Road with a toucan crossing just out of shot. A little further up and walking and cycling get their own space. For cycling this is good because you can avoid the buses which help connect the site to the outside world.

There is plenty of space for everyone (above) and the 3.5 metre wide cycle track feels generous, but at this end of the site, it doesn't really connect to anything, so I assume it will feed into developments replacing the open storage along the Thames to the south. There's also a nice buffer for sustainable drainage.

The cycle track is reasonably smooth and in this part of the world, green is the chosen colour (above). There is no tactile or vertical separation between the cycle track and footway which is disappointing given the site has been developed within the last ten years. The development is still under private control, a fact given away by the private parking signs and patrolling security guards. 

Unfortunately there didn't seem to be much control at the "village square" in the middle of the development where walking and cycling is ostensibly mixed, expect it's made all the more difficult by the car parking free-for all on both sides of the street (above and below).

The other big issue with the layout is the junctions. The separation ends and people walking and cycling have to mix again and indeed give way to motor vehicles (below). Here I wanted to turn right into Minter Road because I was running out of development.

I crossed over and then saw the same kind of layout in Minter Road (below). It just demonstrates that links are easy to design, but junctions need thought and no thought had been given here to prioritise walking and cycling.

Minter Road does have a great feel about it. There is a wetland area with a more formal lake at one end which I assume is all about drainage attenuation, plus it's under electricity pylons where there will be a restriction on building in any case. Apart from the cycle tracks not actiually connecting to a proper network, the main problem with the two-way cycle tracks in the development is residents living on the opposite side of the street don't have any easy way to access them.

There's actually some interesting modern architecture in the development which is in complete contrast to the existing housing stock which is very late 20th Century box-shifter style (below).

Minter Road meets with Mallards Road with an attempt to carry the cycle track through on the main loop (above). It doesn't work well because drivers see a fairly traditional layout with people walking and cycling perhaps assuming priority. The main loop heads back round to Handley Page Road and so we see a triangle spine loop within this part of the development.

Mallards Drive is an older street and there are no cycle tracks so people cycling are back on the carriageway and now mixing with the buses which serve the heart of the wider development. There could have been an extended cycling network being new build, but for some reason it was forgotten. Just off Mallards Drive is Drake Close/ Harlequin Close, a mix of flats, houses and town houses (below).

The dwellings surround a central open space with some fronting and some having back yards/ gardens opening onto it. Again, the open space also provides drainage attenuation. One thing which struck me was the attempt to use the car parking as traffic calming; with the block-paved carriageway and the square it really felt quite Dutch/ Scandinavian.

Sadly, the demands of parking cars everywhere has taken over the good design and rather than maintaining the staggered and subtly laid out parking spaces, the white paint has just stuck them all on one side of the street. In the photograph below, you can see the original parking bay on the right had side of the street in the distance which would have created a stagger with the one in the foreground.

I then carried on up to Galleons Drive with the older late 20th Century housing on one side and the new on the other. The original footway has been designated as a shared-use path, but I stayed on the carriageway and headed west over a watercourse to another section of newer development. 

The separate footway and cycle track model reappeared on Galleons Drive, although the cycle track was a bit narrower than before and someone had forgotten to mark it as two-way.

At the side streets the designers give priority to motors again. The photograph above is the entrance into McAllister Grove which is a small access road forming part of a network of residential streets. There has been an attempt to differentiate the walking and cycling sides at the junction, but with a shared area as a landing to an informal crossing point and a second junction in the distance, we have death by tactile paving and instead of "tram and ladder" style, we have corduroy. It's a total mess.

One thing which was almost done well was some of the car parking along Galleons Drive. It's echelon style with the angle arranged so most drivers would reverse into the space. This means that as they leave the space, they have a decent view of what's happening around them. Unfortunately, some of the bays abut the cycle track leaving vehicles overhanging.

The photograph above is another open space/ drainage attenuation feature between McAllister Grove and Middleton Grove. The housing here includes some single storey dwellings (below) and there are other open space areas, but behind the dwellings with the same private space opening out onto them as I mentioned earlier.

The street layout is pretty compact with the roads design to provide access rather than car parking (below). Although the kerbs to the footways are low, the designers unforgivably forgot to drop them where people need to cross the road.

The original intention appears to have been having mainly off-street car parking (some cleverly hidden within the private curtilages with a bit of on-street provision designed in to the layout. Unfortunately, this has been abandoned in favour of marking out lots of new spaces on one of the footways (Lawes Way, below). This leaves no space to get passed.

Over on the western extent of this phase of the development we have Crossness Road (below) which is a very wide street, yet cycling is given some intermittent paint and you can see some of the parking issues spilling out on the right hand footway.

The northern end of Crossness Road joins the Thames Road industrial area and the south is still under development.

I really tried hard to like what I saw on this little trip and to be sure, there are some nice features and even a half reasonable attempt to try and sort out a street hierarchy. Sadly, though, there are too many mistakes and compromises at both the planning and detail ends of the scale. 

One of the most significant issues is the poor connectivity to the rest of the world. The site has a Public Transport Accessibility Level (PTAL) of mainly 1a/ 1b with some areas of 2. This is what suburban London has which means the use of private cars will still be important or necessary to some residents. There is an extension to the London Overground being built at the moment to the east of Renwick Road which will allow interchange at Barking. 

However, the area is still relatively isolated because of natural and man-made barriers and coupled with the hostility of Renwick Road and River Road, cycling isn't going to be an option, especially with the lack of coherent local network. Sadly, the UK seems to suffer from a malaise of building car-centric developments. Even where public transport is planned, unless it is open and operating for the very first person to move in, the use of the private car is being baked in from day one. 

The other thing to note is that the there were also lots of existing residents and businesses in the area who were forgotten about with transport and their existing travel habits will be tough to change. Frankly, there needs to be a detailed walking and cycling review of the area with investment into making proper changes, including better crossings of the A13/ rail corridor to the north. I shall leave you this week with a video of my spin around the area.

Thursday, 18 March 2021

Designed In Risk

One of the staples of the modern media click bait outrage manufactured culture war is the one where a video is shown ostensibly of a "cyclist" doing something "wrong"; often pivoting to a "who was in the wrong" debate.

It must have some positive effect for the organs that spout this claptrap - and by positive, I mean revenue, otherwise why do it? Maybe it really is a culture war, maybe just clicks for ad payments - who really knows or indeed cares; it is a cultural product of ignorance, indifference and mendacity often displayed by the UK media on many subjects.

What is pretty much never discussed is the environment; the design of the highway space, or how the local authority has decided to treat people (regardless of their chosen mode) either through design or more likely, the gradual creep of bad ideas. This week, I am going to have a delve into a couple of click-bait videos and look at them from a Sustainable Safety point of view.

The first video features at the start of a report by ITV into the introduction of London's Safer Lorry Scheme by the Mayor of London which includes the direct vision standard. The actual video is probably a few years old, but thanks to someone having a Strong Opinion on cyclist behaviour, it was tweeted out and you can have a watch of it here and below;

The video shows a group of people cycling away from some traffic signals in a "turn left" lane with a lorry driver moving ahead in what we assume is an "ahead" lane. All of the cyclists get away from the stop line before the lorry driver, but a couple of them appear to be in the lorry driver's blind spot created by the design of the vehicle.

Start of the video - YouTube/ Simon Burrell

Very shortly, the people cycling have moved right (because of the road alignment) and the lorry driver apparently doesn't see what is happening on their nearside and hits one of the cyclists who does a very good job of keeping upright, the lorry driver immediately stops and all concerned come out of the incident intact - although the video goes on to show a verbal altercation between the cyclist and the lorry driver. 

The driver tells the cyclist that he should know not to go up the inside of an articulated vehicle because that's what is in the adverts and the cyclist tells the lorry driver that he should expect people to be on his inside because that's what happens in London.

The incident - YouTube/ Simon Burrell

So who was in the wrong? Well, I'm going to suggest both people in the incident maybe bear some responsibility (rather than blame), the driver's employer bears some responsibility (because of the choice of vehicle and maybe driver training), the lorry manufacturer has some blame for sticking with such a poor design, but most of the "blame" can be apportioned to the highway authority. Not because of any premeditated negligence, more about years of indifference or lack of funding priority for stuff like this which applies to pretty much every highway authority in the land.

We know this incident was in London because of what is said in the video, but because we can see a large river on the right, we know it's next to the Thames and in fact it's the A3220 Cheyne Walk on the eastbound approach to the junction with the Battersea Bridge. The approach in question looks like this;

A good view from 2017

Just before the view in the image above, the road is single carriageway, it flares out to 3 lanes over a short distance with 2 ahead lanes (right turns onto the bridge being banned during the day with a variable signal) and a short left turn lane of about 10 metres long where the lane is marked. The road returns to a single carriageway soon after the junction, although it's a bit wider this side.

For westbound traffic, there is a similar arrangement of three lanes with right turns banned all the time. Traffic leaving the bridge can perform all movements and traffic on Beaufort Street heading south cannot turn right. People on foot get no green man and so this is very much about shifting motor traffic.

In 2008 the layout is a touch different (above) because the left turn would have taken drivers into the Western Congestion Charging Zone and so the markings hint at the need to make a more conscious movement into that lane. Maybe if that marking had been retained, people cycling may have "taken the lane" a bit more.

So, why were the cyclists up the inside of the lorry, despite what the adverts say? The very short left turn is barely usable for drivers because there will undoubtedly be plenty of queues here at peak times. It's a busy cycle corridor and so an open piece of tarmac to get ahead of the traffic is attractive. People maybe don't think about the risk, maybe the adrenaline is pumping because of the conditions and maybe they haven't seen any adverts.

The lorry driver should have had some awareness of the cycles to his nearside. Maybe he didn't check his mirrors enough (there is a downward facing nearside mirror above the passenger door), but it's hard work driving a lorry on roads like this and it's a high level of tasking for anyone to be able to see what is happening at all times from such a vehicle. Maybe the driver's employer should have invested in a direct vision vehicle and maybe the manufacturer should have stopped making lorries like this decades ago.

From a Sustainable Safety point of view, there are some points to think about;
  • We shouldn't be mixing traffic with significant speed differentials
  • We shouldn't be mixing cyclists with traffic at 30mph
  • We shouldn't be mixing cyclists with high volumes of traffic
  • We shouldn't be mixing cyclists with HGVs
  • We shouldn't be providing road layouts which kill people if any party makes an error
So, would dropping the speed limit to 20mph help? Yes, that would assist to a limited extent on a link (the road away from a junction), but it wouldn't deal with conflicts of the kind we see in the video. Even at 20mph, we are are still mixing people with high traffic volumes and we'll still have HGVs on a road like this, although the direct vision standard makes it much easier for lorry drivers to see what is happening on their nearside.

A direct vision lorry with good nearside and forward visibility

What about education? We can tell people to be careful until we are blue in the face. Some will take heed and remember, some will not be exposed to the education and some won't be bothered. People will still make mistakes.

The solution for this junction is to separate people cycling from traffic. It may be that either side of the junction, basic protection does a reasonable job, but people need to be separated in time and space within the junction. I have had a quick look at the CycleStreets collision data tool which gives some startling, but maybe unsurprising results. Between 2005 and 2019, there were 128 recorded injury collisions in the immediate vicinity of the junction. 17 involved death (1) and serious injury (16), with 4 involving cyclists, 7 powered two wheelers, 2 involving pedestrians and 4 involving a car occupant.

With the slight injuries (111), 28% were cyclists, 26% powered two wheeler riders/ passengers, 8% pedestrians. The remaining 38% was pretty much car occupants. It's a junction which doesn't work for anyone in absolute safety terms based on collisions and those outside of cars come off worst. I haven't done any more analysis (this is not my day job), but the junction screams out for action.

There would be lots of different ways to protect people cycling and it would need to be implemented at a network level with motor traffic capacity would have to be given over to other modes. From a cycling point of view, banning general traffic from turning left into Beaufort Street and onto Battersea Bridge and a permanent ban for the right turn onto the bridge would allow cycle traffic to run with general traffic in protected space. Having a slightly set back pedestrian crossing point could also run at the same time with left turning cyclists being held. Right turns for cycling could be provided as two-stage turns.

The image above is a rough sketch. There are other options and ideas, but this to me is something which could be delivered using bolt-down islands and traffic signal works - offered without detailed thought on actual staging and the network level changes needed to perhaps mitigate the banned turns for general traffic. This would provide protection fairly quickly compared with a total rebuild. It's also worth mentioning that emergency services vehicles could of course ignore the banned turns if required.

There is some work planned by TfL at the junction, announced at the beginning of this year. The immediate works are to help pedestrians with a new signalised crossing on the north end of Battersea Bridge along with a permanent right turn ban onto the bridge. This comes after the death of a jogger earlier this year - it's the natural place to add a crossing given people will want to be on the river side. Later this year, there will be further consultation on crossings on Cheyne Walk (which says 2-stage to me) and another over Beaufort Street. There is no indication of works to protect people cycling as yet.


The second video I want to have a look at involves a cyclist turning right across a traffic lane and bus lane and being hit (I think) by a taxi driver using the bus lane. I don't know if the person who posted it was the taxi driver and I can't find a YouTube link, but here are a couple of stills from the video posted by Coltscabs on Twitter;

The video starts with (I assume) taxi driver moving along the bus lane, undertaking a slower moving general traffic lane (above). The Transit-style van in front of the black car has just come to a halt at the keep clear markings.

The taxi driver continues at the same speed and as they draw level with the van, we see the cyclist on the London hire cycle turning right. The taxi driver doesn't brake until the last moment and hits the cyclist. It's only a short video, but the cyclist gets up and at least appears unharmed. We don't know what happened next, although in response to the post, it's pretty much a stream of abuse towards the cyclist.

Again, we can find the location easily. It's the A3 Clapham High Street at the junction with Gauden Road and the blue paint is CS7. Here's a better view of the location from November last year;

The restaurant on the corner to the left of the bus is boarded up in this image and so therefore, I assume it's very recent. The speed limit here is 20mph and so with a half decent level of compliance, it makes crashes more survivable. By my calculations, the taxi driver was travelling at about 17mph which was good news (relatively) for the cyclist.

So again, we're invited to opine "who's at fault"? Maybe the van driver in slow moving traffic was being polite and left a gap for the cyclist to turn into, only to be collected by the taxi driver. Maybe the cyclist took a chance and expected the bus lane to be empty because they saw no bus. Maybe the taxi driver should have been far more alert when moving faster than general traffic with an expectation that people might turn right.

Going back to the Sustainable Safety approach, we have a 20mph speed limit and for people cycling in the opposite direction there is a bit of mandatory cycle lane (which I think has some wands). The bus lane itself is a bit of protection for cycling, but there could just as easily be right turning vehicles and a bus lane-using cyclist colliding. The layout has been around for about a decade and was one of former Mayor Johnson's awful paint'n'signs attempts at cycling infrastructure.

It's hard to see without the raw data, but again, using CycleStreets, there is a cluster of injury collisions around this junction with maybe 60% involving cyclists being hurt. The problems with a layout like this from a cycling point of view is that there isn't a safe place to turn right from. You can't do it from the mandatory lane because of following traffic, so you have to take the lane, you then have to find a gap in two streams of traffic and in a busy situation, you may not be able to see that second (bus) lane.

It's not just this location, it's a common layout all over the place and so the risk exists at every side street. As well as creating lots of risk to people cycling, it's also a high cognitive load for drivers. The solution here is not easy because the bus lane is clearly something to give bus travel an advantage and we have the classic UK problem of stuffing A-road traffic through a local centre.

The image above is roughly the arrangement now (21m or so wide) and so in theory there's space to do lots of different things, but priorities are going to be tough to deal with. 

The option above removes the bus lane and introduces a central median which would be broken at side streets. The buffer between the carriageway and cycle track would essentially be entrance kerbs at side roads and so a right turning cyclist could could pull to the right hand edge of the cycle track (with other cyclists undertaking). When there's a gap in traffic, they can cross to the "shadow" of the median strip and then when there is a gap in the next traffic lane, they complete the turn.

Drivers would also be able to turn into the median gap to make the turn in two parts. Right turns from the side road would be similar. Of course, side streets could also be filtered to reduce the conflicts.

The option above retains the bus lane, but the cycle tracks are a little narrower and the footways are reduced. In this case, right turns from the cycle track would be physically prevented/ discouraged, as would general traffic turning right across the bus lane. General traffic would have to go a different way (probably via a signalised junction into a filtered area) and cyclists wishing to turn right would also be taken a different way (as part of a planned network) or they would U-turn using a signalised or parallel zebra crossing.

This crossing on Lea Bridge Road, Waltham Forest gives cyclists right turning opportunities with a small detour, but avoiding having to cross two lanes of traffic.

In many ways, this is more difficult a problem to solve than Battersea Bridge because it is a street and network issue rather than a junction and maybe network issue.


So, the point of this post is what? First, it's to show that unless someone is really behaving badly, most of the conflict we see on our streets can be traced back to the street design, whether deliberate or not. It shows that people make mistakes and it invites us to consider the question about whether we really do think it is appropriate to think someone should be killed or injured because of human errors.

It also serves to hold the click-bait media to task because they want to boil everything down to a two-side culture war which doesn't serve society or the public good. If they spent more time asking difficult questions of decision makers and those with power to effect change, then maybe we'd see a better public discourse and less noisy extremism. 

This post also serves to remind us that many of the challenges we have is because of the reluctance to tackle motor traffic dominance in our towns and cities. Once we remove the shackle of "traffic neutral", then we have so much more flexibility.