We Need To Move This Tired Old Discussion On

Last week, there were various news reports flying around about a cyclist who hit a toddler as he cycled along a footway in Blackpool (he has turned himself in to the police).

I am not going to link to the story, you can find it yourself. I am not going to defend the behaviour of the person who hit the child with his bicycle, it cannot be defended. We all know how rare it is for someone riding a bicycle to hit someone walking - the toll from motor vehicles is the real issue. Of course, a news story involving a child and a "cyclist" has some of the media foaming at the mouth - Nick Ferrari on his LBC radio show certainly did last week as he tried (and failed) to bait Carlton Reid who attempted to "de-generalise" the popular canard that all cyclists ride on the footway and are dangerous.

As usual, for me, the story is much deeper. On the surface we have the #bloodycyclists rage for a few days and then we are all on to the next controversy. I have been thinking about why this chap was on the footway in the first place and so let's look at the street where it happened, Collingwood Avenue in Blackpool. I do need to sound the armchair pundit alarm at this stage as I am going by what I can see using Google - I don't know the area myself.

Collingwood Avenue, image from Google Streetview.

The street itself is to the east of the town, with a wide carriageway (perhaps around 9 metres) and footways around 2 metres in width. There is little off-street parking because of the small front gardens the houses have, and so cars are parked on both sides. 

The street hits a signalised crossroads at its southern end (with advanced stop lines for bicycles) and turns into Layton Road at its north end (which soon connects to the A586). About a third of the distance down from the northern end of the street, there is another signalised cross roads with ASLs. It looks like a pretty normal residential street, like we have all over the UK, although the northern section becomes wider and I bet faster on account of the speed cameras.

Speeding traffic? Image via Lancashire Partnership for Road Safety

On closer look, the signalised junctions at each end have Advanced Stop Lines (ALS), there is a sign on the street which indicates "route recommended for pedal cycles on the main carriageway of the road" (yes, I see the irony) and a couple of cycle route direction signs to local destinations. I have also found on Open Cycle Map that this street is a "local cycle route". 

OK, I will come out with it. I reckon this street is awful for cycling - the incident was captured on CCTV (on the house where the toddler lives) and in the 5 second snippet, 3 cars pass the scene at 3.15pm (the incident took place on Monday 18th May). Yes, this is massive (and utterly unscientific) extrapolation, but 3 cars in 5 seconds is busy and I would love to know the truth - with signals in the street, it is likely that groups of vehicles come down as a "platoon" rather than being a constant flow. I will go further, my gut tells me that it is a rat run. The other bit of armchair evidence can be found on Crashmap. Between 2009 and 2013 (the data currently on Crashmap), there were 8 injury collisions, 2 involved those cycling (both at the signalised crossroads about a third of the distance from the northern end of the street). 

Yes, lots of theories and opinions there (and very shaky evidence I accept), so perhaps Collingwood Avenue is a quiet street and people can cycle on the carriageway in perfect safety, but I doubt it. The real story here is why this person was riding his bicycle on the footway in the first place. Was he there because conditions are normally awful and so he rides of the footway as a matter of routine or does he ride on the road elsewhere where it is quiet, it is just that this street is too scary?

It took me about 2 hours to write this post, including research (as much as it was), so why has the reporting been so superficial? Sadly, the shock of the incident is the story for most here, whereas the much wider story which should be reported is how our streets have become so hostile that we get people behaving like this. All very well for an armchair pundit like me and of course talk is cheap. So, what could be done to make this street feel safe? 

We know what the answers are, don't we?

The wider area is surrounded by some pretty large (and classified) roads - these need to be developed for cycling by providing tracks (continued over side roads of course) with time and space at the junctions. The residential streets need to have traffic filtered out of them and returned to the people that live there, along with their visitors and the odd delivery. Collingwood Avenue is not a bus route or a main artery, so it can be returned to access only for motors. 

The speed limit should be dropped to 20mph within the filtered streets (the main roads could stay at 30mph if protection for those walking and cycling is provided). It is a pattern which comes up time and again and should be discussed every time that someone walking or riding their bicycle is hurt on our roads. We need to move this tired old discussion on, it is boring and not changing anything.

What Would Sir Joseph Make Of It All?

Sadly, I don't think people could name a living civil engineer, although they might be able to name a dead one. 

Thorley Lane Bridge on the M56 - yes, bridges don't magically
appear at the click of the fingers. Image from Highways Magazine.

A regular topic of conversation in the dusty halls of the engineering institutions is how can we raise the profile of engineers in the collective mind of the public as well as how we might go about engaging with the decision makers who ultimately decide what is going to be built. I think our problem is that most of the time, we are too busy with the day job to think about promoting what we do and when something does become newsworthy, it is often because it has gone wrong. Think about the chaos earlier at the start of the year when overrunning works brought London Bridge to a standstill, or a whole 90 minutes of delays on the M5 at Bromsgrove due to a weekend closure for bridge works.

This week, we have had the Twitterati laying to CityConnect about the Leeds-Bradford Cycle Superhighway which has now made the front cover of the local paper, the Telegraph & Argus. Now of course, I have made some of my armchair pontifications about the scheme, but I am not blogging about the scheme, just that people have only become interested because of a problem and of course, the engineers are the scapegoats - not the sort of profile we want and no way for us to try and show the public what we can do.

One of the big problems we face is that we are rarely fully in control of the schemes we deliver with politicians and accountants calling the shots and our vision getting watered down by the corporate system and with guidance being applied as standards by those who don't understand what they are doing. Whether it is stupidly raising public expectations that we will be able to complete that railway work in 48 hour line closure at Christmas when we need a week, or where we make contractors keep traffic lanes open as not to inconvenience drivers when we could do a quicker and better job with a road closure or where a pure vision for a cycling scheme has us designing with one arm up our back because we cannot possible shift capacity from motors to active transport.

When I expand my question to allow people to name dead civil engineers, Isambard Kingdom Brunel will often spring to mind, although the fact that he was a workaholic who had many people killed on his projects seems to have faded from rose-tinted view of history. He was a great man of course, but the success of his projects did vary over his relatively short career and yes, he was often criticised in the press at the time. Of course, the projects he built were very much his projects and this is why he is remembered.

Sir Joseph Bazalgette. Image by Lock & Whitfield,
National Portrait Gallery (Creative Commons Licence)

My own civil engineering hero is the lesser know Sir Joseph Bazalgette, another workaholic and contemporary of Brunel, ended up building The Embankment in London. The project was actually a grand scale sewer scheme designed to intercept the sewers of London where they tipped into the Thames, instead sending the waste further downstream to be discharged in an area with no people at the time. Bazalgette had vision on what the scheme should do and it took him a few attempts to convince the powers that be that it should be built (it was horredously expensive). Actually, the Great Stink on 1858 finally convinced Parliament that something should be done as much as anything Bazalgette did.

I wonder what Sir Joseph would make of life in 2015, after all, we are still using the sewers under The Embankment and Transport for London will be repurposing some of the space he created for cycling with the East-West Cycle Superhighway and I wonder what he would make of how decisions are made? I am not in my business to be rich or famous, but I want to improve our built environment and I think that most of my peers have exactly the same motivation. But I do think we need to come out of our shells more and tell the public what we do and why we do it. 

For the continued slating of railway engineering works, I think the engineers need to be telling people how complex the work is, how we are trying to gear up a whole supply chain to operate when everything is closed on a bank holiday and yes, expose the unrealistic deadlines they are given. For the highway maintenance people, when the Lead Member publicly criticises you on how long it takes to get a damaged road opened after a multiple pile up, politely explain that if he his administration had properly funded you, then you could have provided a better service. Designers, when your cycling scheme is systematically dissected on Twitter, perhaps it is time to become transparent and explain the parameters within which you have been forced to work.

Actually, the advice in the last paragraph probably doesn't do much for one's current or future career prospects and this is why it is vital that our engineering institutions pick up on some of this criticism and give the counter arguments. Of course, we should also admit when we have got it wrong and I know this is difficult, especially if it is unpalatable to those we are working for. It is also important to keep our vision and to record it because when we have our own Great Stink, we need to justify our position. Perhaps then, the public will realise that they undervalue us and actually, all the great people are civil engineers and well as civil engineers being great people. But, I am bound to say that aren't I?

PTALs, Parking and Power

I'm sorry, but this is another London-centric post, but three things of interest caught my attention this week which have some linkages.

First up was the launch of WebCAT by Transport for London which is a transport planning tool which can be used to look at public transport connectivity across the Capital. Three systems are available on a map-type interface; PTAL (Public Transport Access Level) which scores locations based on their proximity to public transport and its frequency, TIM (Travel Time Mapping) which shows how far one can travel within a defined time and Catchment Analysis which shows how many work places or different types of services exist within a certain travel time of a place. The system replaces the TfL Planning Information Database which was also web-based, but showing its age.

The graphic above an example of a PTAL output for a location in the centre of Stratford and unsurprisingly, it is the highest at 6b. The graphic to the right is a TIM output centred on Abbey Wood Station and is a series of isochrones of travel times from that location.

I have only just started looking at the tool and there is much more to it than I have set out. For the day job, I will use it to double check PTALs for development sites which will have a link back to local planning policy on the parking provision that one would expect to be provided for a site. Where PTAL is at the highest end, the provision will be less than one parking space per unit and where the score is at the lowest end, it will be 1.5-2 spaces per unit. There are variations for density and unit type, but I shan't go into detail here (the parking standard relates to off-street parking).

This brings me onto the next thing and that is parking standards for developments and a "minor alterations" consultation on parking standards which is running now. The consultation has come as a result of the Government agreeing with the Mayor that parking standards in Outer-London need reviewing. The Minister of State for Housing & Planning wrote to Boris in early 2015 stating;

This Government is firmly of the view that more parking spaces should be provided alongside new homes that families want and need. This is especially the case in areas where access to public transport remains low. But even in urban areas, an insufficient number of parking spaces - which may be caused by maximum parking standards amongst other reasons - risks creating a 'vicious cycle' where clogged up streets leave motorists to run the gauntlet of congestion, unfair fines and parking restrictions."

Well, I suppose this unified approach from the Mayor and the DCLG doesn't come as any surprise given the politics (in general) of Outer-London. The issue they are attempting to address is that in Outer-London, many areas have low PTAL scores and so people will rely on private cars to get around. We have had maximum parking standards for years now (if a developer proposes more than 2 spaces in a low PTAL area, it is technically a material reason for refusal) and the perception is that lack of off-street parking has and is clogging up our streets with over-spill. 

I have some sympathy with the issue, especially where people work beyond the boundary of London and let's be honest, public transport is pretty sketchy and cars are used (the PTALs are low of course). The Mayor could of course look to influence Outer-London policy and improve public transport and I suppose he is in places (Crossrail for example), but unless you are travelling to a town centre, moving around the outer boroughs can be a problem by public transport. I also agree that over-spill parking is an issue, but there is only so much kerb-space and boroughs can control use themselves to deal with the issues.

Thinking about my own area, for parts of the borough with a low PTAL (2 and under), the parking standard is 1.5-2 parking spaces per dwelling for houses and 1-1.5 spaces per unit for flats (as a generalisation) and this is repeated across many outer boroughs (with local variations). The proposals in the amendment actually reflect what is policy in Outer-London boroughs anyway and so I cannot see much changing in approach, although it is telling that for PTALs of 0-1, boroughs should be considering higher levels of provision - executive homes anyone? The London Plan was always for lower standards and this is something which has caused political tensions. It is also worthy of note how we have provision for electric vehicles (EVs) woven into the policy which brings me on to the third thing of interest this week.

I had a pop at how the Government was pushing EVs a couple of years ago and they show no signs of stopping. Using public subsidy to help people purchase EVs, the motor manufacturers clear know that the writing on the wall is there for petrol and diesel and so there is heavy investment in clean alternatives (so long as the electricity is renewable of course). I have no issue with the technology if it is applied to buses, vans and taxis and perhaps car clubs, but replacing one fuel for another won't deal with the parking issues and poor PTALs discussed above. 

One of the biggest issues for EVs is so-called "range anxiety" which is the worry that one will run out of juice and get stuck. Those of us who use public transport can empathise when we miss the last train or bus home! The way to deal with range anxiety is to establish a network of recharging points so that people can stop to top up their power or trickle charge overnight. In London, things have not gone well with lots of different systems (some public on-street, some in private car parks), sporadic maintenance, charging points often out of action, no proper network and a lack of a unified system - as a result of planning policy I would add. TfL took the lead and set up Source London to try and run the system on a city-wide basis, but this was sold on last year to French industrial, Bolloré Group's sunsidiary, IER for £1 million. Bolloré has fingers in world-wide pies including transport and electricity storage systems.

IER has been negotiating with London Boroughs and private operators to take over existing charging kit and to roll our a proper pan-London charging network. Where on-street charging points are concerned, they are also seeking to get dedicated EV parking bays provided (with revenue for the local authority) and the whole thing bundled up to be simple for members of the system to find and book charging places. There is ambition here and IER is taking on huge risks to make this work beyond what TfL could ever have done.

Of course, this all means that for private car journeys, the policy and investment in London will conspire to keep those Outer-London PTALs low and allow the free movement of private motor cars across the Capital with all of the the safety, heath and societal problems it brings. EVs are also exempt from the Congestion Charge and so there is an obvious attraction for the Outer-London executive in their multi-parking space home to ditch the train in favour of taking the Tesla S to the office. Me? I'll stick to my bicycle.

Beyond the Bicycle

This week (Wednesday 6th May) I attended a seminar on inclusive cycling which was being jointly held by the London branch of the Chartered Institution of Highways & Transportation (CIHT) and the London Cycling Campaign (LCC).

I don't know if these to groups have ever met like this before, but it was a cracking idea and I really hope it happens again. Of the 40 (my guess) or so people who attended I think the split was about 50/50 campaigners and engineers, although there were quite a few of us there who belong to both organisations!

Rachel Aldred shows us that we need to be designing for everyone

Perhaps it is a sign of change in London when a meeting like this; perhaps the silo mentality is gradually breaking down. I certainly hope so. Chair for the evening was fellow CIHT and LCC member, Philip Loy who introduced three speakers who I am sure many of you know (at least on Twitter!); Dr Rachel Aldred of the University of Westminster (yes another CIHT and LCC member), Isabelle Clement of Wheels for Wellbeing (self-confessed fair-weather hand-cyclist) and Phil Jones of Phil Jones Associates (another CIHT member, and as he spends so much time in London on a bicycle, I am hoping a potential LCC member!).

Now, I was there to learn and although I attempted a bit of live tweeting, I did get absorbed into the discussions and so this post I guess is a summary of the highlights or interesting points (for me at least).

Rachel Aldred's theme was essentially why inclusivity matters and how it should be central to good design (in its widest sense). Something which is designed to assist and enable specific people will also help the wider population. She went on to explain that cycling is a way to enable people move independently, even when walking might be difficult, and so we should be concentrating our efforts on designing for under represented groups as after all, we get the people cycling who we design for. 

The next good point made by Rachel was that the Equality Act 2010 gives local authorities additional duties, including the important "equality of opportunity" which extends to being a transport provider (i.e. highway authority). When put in cycling terms, it means that designs which are not usable by all will deny the opportunity of use to some, and so the "old" way of designing may arguably be indirectly discriminatory. My observation was that highway authorities need to up their game as a challenge under the Act is bound to happen. 

Isabelle Clement spoke next and started with a personal history on how she came to hand-cycling, starting in parks and then gradually moving up to using the roads, but as a way of getting from A to B; although she admitted that she was rather fair-weather! She did explain that she had been going through a steep learning curve on the technical side of things, but at least knew what a splay kerb was - nice!

The serious part of her talk was that "we" have been designing for people who can walk their bicycle, lift it up steps, cope with kerbs, can stop and stay on the saddle and so on - in essence a narrow group of people. She explained how traffic calming of various types presented significant disadvantages to many people such as those using tricycles and hand-cycles. Speed cushions, for example, were cited as a particular problem for cyclists on more than 2 wheels. She also suggested that we had forgotten about those using trailers, cargo bikes and we really need to be designing "beyond the bicycle" which is a great way to put it.

Phil Jones then spoke about some of the design standards and engineering which needs to go into inclusive cycling. He reiterated the narrow nature of the target cycle user so far which was telling given the front cover of the official government guidance in Local Transport Note 2/08 (see left). He said that regular cyclists are most likely to be male, white, in work and non-disabled.

He went on to say that LTN 2/08 does recognise children and disabled people, but it all gets rather vague and is out of date. In terms of the Equality Act, it is referenced in the new London Cycling Design Standards which also sets out a range of different types of bicycles which need to be designed for. Beyond that, he said that the Wales Active Travel Design Guidance has looked at inclusive cycling and on that aspect was ahead of the Dutch and the Danes!

At the discussion/ debate at the end of the session, there were some good points made and questions asked. Isabelle said "cycling cannot be survival of the fittest" which was a double-pointed issue in my mind in terms of how people often have to cope now, and how the conditions put so many people off.

A question was asked about what might happen after Boris if we had a less interested Mayor. It prompted comments about the Mayor perhaps not being that interested (half-jokingly), but the panel felt that despite a lack of National guidance, London seemed to be doing well at officer level within TfL which would give continuity as after all, politicians always come and go.

L-R; Philip Loy, Rachel Aldred, Phil Jones & Isabelle Clement

There was a point made about needing standards to take us beyond guidance as engineers want to be able to refer to numbers and parameters and in turn they would be pushed to do better. The panel was warm to the idea, but standards would have to cater for all users. Phil made the point that Highways England would be releasing an Interim Advice Note on inclusive cycling and while aimed at trunk road schemes, it would provide a "design vehicle" which if used to design a scheme, would cater for all.

We had a question about the gap between design standards/ advice and what we can afford to build with the gap getting greater as new standards get better. Rachel said that there were always underspends in London (so money is not necessarily the issue), but it would be better to go for the highest standards and spend properly on fewer schemes. This led to a point about campaigners using the new LCDS to measure the quality of current TfL and borough consultations. On the subject of boroughs, a good point was made about staffing cuts being a huge issue with volunteers often being expected to take up the slack.

The final point of interest for me was raised by Isabelle on how some protected infrastructure can create access problems for non-cycling disabled people and how this can create tensions. She felt it really important that both cycling and non-cycling disabled groups engage with each other to find common ground and compromises.

Yes, an excellent session which leaves me with this thought ; for engineers "beyond the bicycle" should mean that we are designing for inclusive active travel with high levels of experienced safety. As well as applying to those riding bicycles, it equally applies to those walking.

Update 14th May 2015
You can access the talk slides and audio here.

On The Level

This week's post is inspired by a tweet by Brenda Puech about the difficulties faced by wheelchair users in negotiating footways which have poorly arranged and steeply sloping vehicle crossings to private property.

Twitter is great at feeding me ideas for posts and in this case, I think Brenda has raised an excellent point which is (mostly) easy to deal with, so a big thank you her.

So, to the basics. We are dealing with "vehicle crossings" which is dealt with under S184 of the Highways Act 1980. It is a power that the local highway authority has where someone needs to (or already is) taking a mechanically propelled vehicle over a kerbed footway or verge. (don't worry, I am not going to describe the detail of S184!) I would add, that we can also be dealing with private roads meeting the highway and a vehicle crossing could even be the norm for side roads meeting other roads, the so-called continuous footway or "blended junction".

The provision of a vehicle crossings is a power rather than a duty and there is no automatic right for someone to have one installed. For example, if we have an accessible bus stop, putting a vehicle crossing through the middle of the waiting area will remove accessibility and so the highway authority has every right to decline a request for a vehicle crossing. It is quite useful to have a policy in place to help deal with applications though.

So, to the point. What makes a good vehicle crossing? In fact, what makes a good footway in the first place? For the detail, you can refer to "Designing for Walking" which is free to download guidance from the Chartered Institution of Highways & Transportation (CIHT); Section 6.3.1 covers vehicle crossings and Section 4 some more general matters on footway design. For this post, we are mainly interested in the crossfall of the footway and what happens with levels along the line of travel, as well as footway width.

The basic point of a vehicle crossing is to allow people to drive between the carriageway and private property and so most of the time, this involves dropping the kerb from a "full height" to a "dropped" kerb. There are lots of different kerbs out there, but in most situations we will have kerbs with a "face" (height about the carriageway surface) of around 100mm to 125mm (yes it varies). We will then have a pair of transition (ramped) kerbs which take us down to the dropped kerbs which will have a face of about 15mm to 25mm. The face on the dropped kerbs is useful as it helped visually impaired people know that they are at the edge of the footway (as well as "feeling" the slop to the dropped kerb).

In usual circumstances, footways will have a crossfall of around 1 in 50 (2%) from the back to the kerb. This is needed to make sure water drains off the footway into the carriageway as standing water would be an ice risk in the winter and not very nice to walk through at other times. If the footway is laid in asphalt, the skill of those installing the surfacing will be telling in terms of water still getting trapped if the surface isn't laid flat enough - I am starting to think we should machine-lay asphalt footways and strengthen them to enable machine lay (structural design of footways is a subject for another day).

When it comes to dropping the footway for the vehicle crossing, many people will just increase the gradient to cope with the lower kerb. For example, a 2m footway with a full-height kerb face of 125mm which drops to 25mm could go from a 1 in 50 crossfall to 1 in 14. For many people, this change in gradient is difficult to cope with and for everyone else, it is like trying to be a mountain goat!

Imagine if there are vehicle crossings like this for each house you pass, each going from a 1 in 50 to a 1 in 14 crossfall and back each time - how very tiring to walk along and of course a much greater problem for those using wheelchairs, pushing buggies and so on. The other thing with this arrangement is that at the rear of the footway, the level along the direction of travel stays the same, but at the kerb, there is also the slope down to the dropped kerb to think about. The stock ramp kerb is 914m long (3 feet) and the transition provided is 100mm, which gives slope of 1 in 9. When we consider the usual pedestrian dropped kerb gradient is 1 in 20 (1 in 12 maximum), then 1 in 9 is also significant. The narrower the footway, the greater the problem too.

So, how can we make things easier? CIHT recommend that a level "landing" of at least 1m is required. In practice, this means keeping the rear 1m of the footway at 1 in 50 and then only sloping the front part down. With our 2m footway example, this means that the front part of the footway (1m) would have a gradient of 1 in 8 which is steep for pedestrians to use, but no effort to drive over (at a suitable speed). 

The reason for the 1 metre platform is that it is seen as the minimum unobstructed width needed to walk along, use a wheelchair or push a buggy. This might be fine with the odd vehicle crossing, but where there are lots, then we quickly end up with an effective footway width of only one metre by default and it is no good if people want to walk side by side.

There are other options available to us. Where there are multiple vehicle accesses to property, it might be better to drop a complete length of footway with gentle slopes at each end (which will need thought with laying the kerbs right at each end - remember a transition kerb is a 1 in 9 gradient). It does mean the levels at the rear of the footway need to be looked at as these will need to be dropped too which can mean doing work on the "private" side to get it working right.

CIHT also suggest using one of my favourite kerbs, known as the quadrant kerb. To be honest, nobody on site calls it a quadrant, it is affectionately known as a "cheese" because of the passing resemblance to a lump of Edam! The kerbs are available in two stock sizes (the 455mm one being more robust) and is compatible with standard UK kerbs. It is possible to get much larger ones made in natural stone - I have used 1m radius ones to form dropped kerbs at pedestrian crossings in the past.

The quadrant kerb used in our 2m wide footway example gives another half a metre of usable footway and the other advantage is that people need to be really careful driving over them - moving slowly which is a good thing as far as I am concerned.

The quadrants are installed as in the diagram to the right and they allow most of the footway to stay at he same gradient. The area between the quadrants is then ramped down to the dropped kerb level. The use of quadrants is not always something people like because of the risk of someone tripping over them, but I would argue that people tend to walk in from the kerb because of traffic and a wider usable footway is the bigger concern.

There is a variation on using quadrants with a little slope and that is using special ramped kerb units. The photo to the left show a unit about 300mm wide which with the special transition kerb go to form the ramp wholly within the kerb line. The normal kerb in the photo onto has a kerb face of about 50mm and so the slope on the kerb is gentle for drivers to negotiate. This arrangement is often seen elsewhere in Europe, although kerb faces are also often lower than in the UK which makes the transitions easier - perhaps we should lower out standard kerb units? Of course, we don't have to lay kerbs with a 125mm kerb face, we can use standard units to lay them a little lower, but it is an issue which people don't seem to think about.

A nice way to accommodate vehicle crossings is by using a grass verge. The main part of the footway can be left with the gentle crossfall and the front of the vehicle crossing can be ramped within the line of the verge. The use of verges is also nice because we can plant trees and install lighting columns and signs without creating clutter for those walking.

I suppose for some people, the ultimate in providing level surfaces is the establishment of a shared space scheme. I will be blogging about the concept later this year, but it is worthy of a mention here. My caveat is that I only think the idea works in very specific circumstances of vehicle access and low speed (I mean walking pace), but that will be covered another day. 

The photo on the left is a little one-way street which is under construction at the moment. The reddish area is the "carriageway" and the grey area the "footway". I state in quotes because the whole thing is a level surface. While not a boundary to boundary treatment in the same materials, this is a form of shared space and its success will be known in time. From a vehicle crossing point of view, there were no levels to accommodate and so for the "footway" area is really flat and easy to use (this would be a similar case with access taken from a speed table, although a small kerb upstand would normally be used).

The entire area is built to carriageway standards and so the "footway" can be overrun. The important point here is that the parking is designed into the scheme so that anyone parked on the "carriageway" will block the street to vehicles and anyone parked on the "footway" is at risk of a parking ticket as this is a London site - time will tell on this (developer designed) site. 

Whatever type of vehicle crossing is used, it should be constructed to take vehicle loading. It doesn't necessarily need to be designed to take a 40 tonne lorry, but it should be substantial enough to take regular use by light vehicles. I don't think we construct our footways that well in the UK (at least outside city centres) and would advocate building them to a better structural standard anyway.

To get things really right I want to describe the tricky issue of "accommodation works". When I was a junior engineer doing mainly maintenance works, I was fortunate to work for a really good principal engineer who considered maintenance work as something rightly needing the same care and attention as new build. When it came to a footway reconstruction scheme, he was always eager to get the levels right to best serve pedestrian comfort and this has stayed with me over the years. 

Accommodation work is the practice of entering private property and (with agreement) adjusting levels. This means that footway levels can be gotten spot-on for maximum improvement those walking. So fanatical were we all about accommodation works, that around 10% of a footway renewal budget was given over to the work. The image from Google Streetview above is a footway scheme I did about 15 years ago. The "joined" on strip of concrete is actually on the private side of the highway boundary and allowed the rear of the footway to be laid level. In the most extreme case, we relaid about a third depth of someone's driveway to get the levels to work properly. Getting this right takes time and effort, but it is worth it.

And finally (hooray I hear you scream) I have to mention cycling. In thinking about situations where people need access over a cycle track, much of what I have written applies because we want to keep the riding conditions comfortable.

The photo on the left shows Old Shoreham Road in Hove which has a stepped cycle track for each direction; that is the cycle track is lower than the footway and the carriageway is lower than than the cycle track; with kerbs doing the stepping down.

What this has meant for those walking is the kerb height between the track and the footway is quite low and so the vehicle crossings don't need much ramping down to the track which gives good levels of comfort for walking. The cycle track kerb height is also low, so the creation of vehicle crossings over it are not obvious as one cycles along. A good example of cycling infrastructure assist those walking and cycling.