Decembers Delve into Christmas Chaos

It is time for my monthly instalment of rail ramblings. Like many parents preparing for the festive season I'm a bit behind schedule, and clinging on to the faint hope that festive good cheer will carry me through. Santa needs to bring me another fortnight so I can fit everything in!

Snow

In the UK, (where I am), the south of the country has had a little snow and as usual if you listen to the TV news, the world seems to have ended with the ensuing travel chaos it brings. The cold spell which I mentioned in a previous article did quite predictably have some impact with several broken rails causing delays, but the effect of snow and ice on 3rd rail electrification was what caused most sparks to fly. (old YouTube video below for illustration).

The issue here is the 3rd (electrified) rail has the contact surface on top of the rail which can get covered with snow and ice interrupting the flow of electricity with some spectacular results. There are things done to try and avoid this issue such as running empty "ghost" trains around to clear the snow and ice or applying de-icing fluids to the conductor rail, but as snow doesn't often cover the south-east of the country, it is a problem we just have to live with on the few days of the year they have significant snow fall. Similar issues can occur icing overhead electrification wires, but due to their location, higher voltage and more flex as a train passes, usually these issues are less severe although do need to be considered. If you want to find out more on what makes these electrified rails special then you can find more in my recent #rail101 article which explores them in more detail here (5 min read).

Strikes

No I'm not going to talk about lorries bashing bridges (Although this one got struck by a lorry and took 3 weeks and partial demolition/replacement before it was safe to use!)

I am of course talking industrial strikes. I try not to get political on my posts, but as much of the UK rail industry is currently gripped by industrial action in an ongoing dispute which the government keeps interfering with seemingly preventing a speedy resolution, it would be remiss of me, not to at least give it a mention. Our rail networks depend on people to operate them, and that vital human part of our network is ignored at your peril. Whatever your political persuasion, without a workforce you are on the fast track to no-where. And of course it isn't just the railway workers who are taking action too.

Whilst I certainly sympathise with the workers cause, the ongoing and escalated action does drive people away from the railway (sometimes quite literally) and that transport habit is one which could affect the volume of passengers for years to come. I hope things are resolved in a practical way soon, for the people, the industry and indeed the climate too.

And Finally... Why doesn't every city have trams?

Rather than just digest some of the recent rail news, I'm going to try and touch on a rail challenges in a little more detail in this and future issues. Let me know what you think?

Tramways are often seen as a great step to making city transport more pleasant and more sustainable, (street-car or trolleys to my North American readers). However, anyone who has lived in a city whilst they are being installed knows just how disruptive the construction process can be, and also how expensive networks are to create in an existing cityscape.

Why is this the case? Why can't we just slap some rails down on the street, string some wires (or even use battery trams in some cases). Well they say a picture can say a thousand words....

The services buried in our streets usually need to be moved or buried deeper in order to construct a traditional tramway. The depth of construction required determines a significant chunk of the project costs. So what can we do to avoid these?

Go shallow

There are some innovators in the market trying to reduce construction depth significantly. There is a modular slab track approach essentially hoping to place prefabricated slabs over the top of services rather than having to go to the expense of diverting them. One such system is PCAT but there could be others. A perhaps complementary strategy is to use rails that are shallower. Why should a tram rail embedded in a road be taller than one supporting a heavy freight train? It doesn't make sense, but it can often be the case for reasons of history. I've seen a few trials and demo's but neither of these approaches have gained a huge amount of traction yet, I guess the rail industries reputation for risk aversion isn't unfounded. But, I certainly feel there is merit going back to basics and using modern techniques rather than those from yesteryear. The financial and sustainability benefits are simply too big to ignore.

Go light

Another perhaps obvious approach is to make the vehicle smaller/more lightweight and therefore the structure supporting it can also be similarly scaled down. With some tram's having axle loads over 10 tonnes, the benefits from looking at more lightweight solutions to avoid deep digs is attracting attention. Very Light Rail (VLR), is one option particularly for smaller cities who simply cannot justify a traditional tram system in both cost and size. The vehicles which aim for a weight less than one tonne per metre in length and axle loads below 5 tonnes are significantly lighter than traditional trams which are approaching twice that value. There is a good article about VLR here (7 min read).

Go up

Of course whilst most people try to think laterally to solve the problem of digging up the street - some seek to solve it vertically and place their systems above the street on elevated piers or other street spanning structures. Generally not a great idea from cost, maintenance or accessibility perspectives, but, there are still some systems that have taken and survived this approach.

Go rail-less

As the video above finishes often the bus is seen as a lower cost and more flexible choice. Technology evolves too and bus manufacturers attempt to blur the lines between bus and tram with longer articulated buses with disguised wheels, and even battery powered bendy buses that can follow virtual tracks on the road. However rubber tyre vehicles all suffer from the same efficiency penalty that rubber on road gives. (typically 10 times the rolling resistance of steel wheel on steel rail), as well as the safety, air quality and noise issues they often bring too, (some cities have previously banned bendy buses from their streets due to safety concerns).

So which is best?

As is often the case there is no one answer fits all. If there was, we would all have cities that looked the same. The one aspect I've not mentioned so far, but ignored at your peril, is integration with other transport types which can make or break a systems success.

Our streets are there to service the needs of the city and its inhabitants. It is therefore somewhat ironic that the services we have buried beneath our streets make installing better and more sustainable transport quite so difficult!

Summing up, an engagement plea and touting for work

Thanks for bearing with me this far. If you love these newsletters - subscribe comment and share. If you hate it - tell me why in an amusing way so I can make it better.

As my current contract nears its end, I'm seeking new challenges, so get in touch if you think I could be an asset to your team.

Thanks having your tea-break with me - I hope it was a good brew.

Until next tea break my friends - Stay safe, tread lightly on our world and if you celebrate Christmas, have a fun filled and family soaked time.

Dan