What’s Causing Those Potholes?

Potholes are so annoying!  I know we need to be grateful that most of our roads are sealed and aren’t rutted, but a pothole was bad news. They were bad news even when roads weren’t sealed and ruts were common.  The shallow ones bump you so hard that not even the world’s best suspension system can cancel it out (unless you dodge them), and the large ones can damage your car (more on that below).  If you try to dodge a pothole, you can put yourself and/or other drivers at risk/ In the case of some modern cars that have driver aids that were designed for and tested on perfect roads, things like lane change assistance might throw a wobbly if you detect a pothole in the road ahead and adjust your driving line carefully to avoid it (the systems are smart enough to shut up if your movements are abrupt).

Why do potholes appear?  Why does what used to be a perfectly good piece of road suddenly look like a teeny asteroid hit it?  Are heavy trucks and road trains to blame?  And what can you do about them?

The thing that causes potholes is nature striking back.  They are caused by one of the most powerful elemental forces in the world: water.  As you’ve probably seen at some point in your life, whether it’s a catastrophic landslide, a cliff eaten away by the action of the sea or just a rut in your garden after someone left the hose on for too long, water sweeps away and acts on dirt. And it’s water that causes potholes.

Now, it’s not the case that a pothole will appear where a puddle has been.  It’s true that both potholes and puddles will form in parts of the road that have slumped or become rutted, but one doesn’t directly cause the other.  There are other factors at play.  The condition of the road is one of them and the amount (and weight) of traffic is another.

Water will get into the soil beneath the road and start loosening the particles of dirt, meaning that ruts and holes will form.  This has always been the case ever since roads were invented.  If anything, the whole point of road surfacing is to have something that doesn’t form ruts and holes every time it rains so that wheels can run over it smoothly.  The different layers of a modern paved road are designed to ensure that water drains away well (and that the road will hold its shape despite heavy trafficking – but that’s good story for another time) with the asphalt over the top forming a mostly waterproof and resilient seal.  However, nature will always prevail, and water will get in.

Once the water has got in, the most common thing that happens next to create a pothole in Australia is that the water will start washing away small, fine particles of dirt, then larger particles, and then a bit more.  This will weaken the ground beneath the asphalt surfacing, as there’s less holding it up.  As traffic goes over it, the asphalt surface will be pushed down a little, not so much that you’d feel it but still a little.  And this compresses the water, which increases the pressure it exerts on the surrounding particles of dirt.  Eventually, a characteristic pattern of cracks will appear on the surface of the asphalt, known as alligator cracking because the pattern looks like the skin of a big old croc.

Eventually, the friction from tyres rolling over the asphalt will break some of the surfacing loose, exposing what’s underneath. The hole will soon get wider and wider, and you’ll get a fair dinkum pothole, and it will get worse and worse the more the water gets in.

Water in its liquid state is the primary cause of potholes in Australia, although in parts of the country where you get frosts – and in other parts of the world where winters get particularly savage – another factor is at play. Water expands as it freezes, so any water in a tiny crack of the pavement or beneath the surface will expand. The asphalt, however, will become more rigid and brittle, so the expanding ice will break the asphalt and crack it more, which accelerates the process of a pothole forming.

Generally, the wetter things get, the more quickly potholes will form.  This trend has often been noticed; in fact, Shakespeare makes a passing reference to it in one of his plays, where a character compares a stupid, pointless and completely undeserved action to fixing highways in summer.

There is nothing that you personally as a driver can do to fix a pothole. That’s the job of the local roading authority. In an ideal world, these people should inspect the roads and take action to resurface and to improve the drainage as soon as they notice signs of alligator cracking.  However, in practice, we tend to see that the problem gets a temporary fix in the form of asphalt being slapped into the hole to fill it up.  This works for a short time, but if poor drainage is what has caused the water to get in and pool beneath the road, another pothole will appear before long.

Ideally, you should drive around a pothole rather than letting your wheel run through them.  If you drive through one, it can cause a lot of damage.  Tyres are the most vulnerable. The most immediate and dramatic type of damage is if the rough edge of the pothole punctures or rips the tyre. However, there are more subtle types of damage.  Going through a pothole can also cause sidewall bulges by forcing the liner apart from the sidewall – and these bulges can blow out very easily.  If the rims are damaged or the alignment is thrown out by going over a pothole too fast, this will make the tyre wear out more quickly and unevenly.

The damage doesn’t stop there.  The shock of going through a pothole will also put a strain on the suspension and steering as well as on the general alignment of the wheels (they’re all interconnected).  This won’t happen straight away, but it will be made worse by continually going over rough roads and hitting potholes (e.g., one that’s on the road you take to work during rush hour, meaning that you have no choice other than driving over it).  In the worst case, which is going into a very deep pothole that the local authorities should really have done something about ages ago, the undercarriage and exhaust system can be scraped and dented as well if it hits the undamaged surface of the road.

In the case of EVs, damage to the underside of the vehicle is particularly serious, as this is where the battery is.  The battery is protected by an underfloor protector, which is like a suit of armour for your EV’s battery.  However, if this underfloor protector is badly damaged, the battery becomes vulnerable and could go into thermal runaway (i.e., catch fire).

Obviously, if you see a pothole, you should avoid it.  If the traffic is light and the road is wide, this isn’t a problem.  However, in heavy traffic, going through that pothole may be unavoidable, as the results of hitting another vehicle would be much worse than the results of going through a pothole.  However, the damage will be less if less force is involved, so dump some of that kinetic energy by slowing down, preferably well before you get to the pothole so you don’t bang on the brakes (however, banging on the brakes will be easier on your car than driving through a pothole, especially if you have brakes with all the driver aids). 

Lastly, the question as to whether trucks are to blame for potholes. The answer “yes but”.  Yes, trucks are heavy and the extra weight wears out the asphalt more quickly.  However, cars are getting bigger and heavier in general, and EVs are particularly heavy compared with their ICE equivalents.  However, the roads are still built to the old specifications for lighter vehicles, and don’t stand up.  What’s more, budget cuts and cheapskate roading authorities mean that roads may be built to meet the bare minimum specifications rather than exceeding the standards for extra durability and resilience.  Perhaps it’s time for the standards to be revise to meet the current vehicle fleet, especially if the government wants greater uptake of the heavier EVs.  

Why You Need To Stay Alert During Winter (Even In A Car With All The Driver Assistance Features)

No review of any car produced from 2010 onwards would be complete without a list, or at least a partial list, of some of the driver aids.  Most of us have noticed that cars have become more electronic and have more computer-controlled gadgets (and we may have grumbled about it if we are DIY mechanics who know how to use a spanner but go to pieces when confronted with anything containing a chip).  The list of driver aids seems to be getting longer and longer, starting with basic things like rear view cameras and going on to things like traffic sign recognition, lane departure correction and more. 

There’s no denying that these aids are very useful – I love the reversing camera we fitted onto our Honda Jazz – but it’s important that we don’t become too reliant on them.  Even though it may seem as though the clever people who design these systems and sensors are trying to replicate a horse (autonomous, 360° audio warning system, 210° cameras, voice activation, carbon-neutral, emission-free, running on 100% biofuel and completely biodegradable), one has to remember that your car isn’t actually intelligent – like KITT from Knight Rider – and isn’t a horse, and those sensors and systems can have problems in certain conditions.

These conditions tend to crop up a lot in wintertime – the time when driving is most hazardous.  One reason why this happens is because the sensors are located on the outside of the vehicle (obviously).  On wet days, mud and slush gets thrown up over your car by other vehicles on the road, and this can obscure the sensor. Even something as simple as condensation can cloud the sensors, not only in its own right but also because the condensation can collect dust and because that condensation can freeze if the temperatures go below zero.  This is annoying in the case of cameras but absolutely wreaks havoc on all of the other safety systems that rely on the cameras.

The field of image recognition is a hot one for experts working in the field of AI and smart machines.  However, this is because we can do it all the time without thinking about it.  That’s why those CAPTCHA “prove you’re not a robot” tests often ask you to select all the squares with images of things like motorbikes and traffic signals. (Some suspect that your answers don’t just prove that you’re human but they’re also used to train computers to recognize these items, which is probably why you’re asked to identify things that a smart car might have to identify.)  If you’re paying attention, you can identify an oncoming truck on a rainy day, and you can rely on a range of cues to tell you where the side of the road is.  Computers don’t quite have this ability, as rain, hail, snow, slush and fog make things tricky.  If your car’s Advanced Driver Assistance Systems (ADAS) have been trained on scenes of, say, traffic signs or lane markings that were taken on sunny days, the system will struggle to recognise a traffic sign that’s obscured by fog, has a possum sitting on top of it, has snow or frost covering some of it, or has been used as a target by someone with a shotgun. ADAS can’t extrapolate where the lanes are from a little glimpse of road that’s otherwise covered by snow or piles of hail.

Systems based on radar, such as pedestrian detection and advance collision warning systems also have trouble in cold, wet windy weather.  Although fog and frost aren’t a problem for radar, rain, snow and hail are problems.  This is because of the way radar works: the radio waves go out, hit something and bounce back, and the time between the signal going out and when it comes back can be used to calculate the distance (or the speed, in the case of police radar systems).  However, the radio waves will bounce off anything and be scattered by anything, whether that thing is a hailstone or a heavy truck.  Contrary to the rumour going around that radar systems don’t work in the rain, the truth is that they do work – they just don’t work as well.  This means that if your car’s ADAS is radar-based, then it might not do quite as good a job on a rainy day.

What this means for you as a driver is that during winter driving conditions, you need to be extra alert – as alert as you would be if you didn’t have all those ADAS in place.  For years, we’ve been told that during winter driving conditions, it’s important to slow down and take extra care, and this advice still holds even if your car has all the ADAS bells and whistles.  As all car manufacturers are quick to point out, even the fanciest systems are not intended to replace good driving and safety is ultimately the responsibility of the driver.

If you have those sensors and you like to use them (like me and my reversing camera), you may need to wipe them down a bit more often during winter (a paper towel will do the trick).  If you’ve got frost on the sensor – which will probably happen if you have frost on your windscreen – then give the sensor a bit of a slosh with the warm water you have probably used to get the ice off your windscreen. Then drive safely!

Your In-Car Emergency Kit

Winter is a difficult time to drive in, as conditions make things more dangerous.  Depending on where in the country you are, you may have to cope with a lower angle of the sun, which gets in your eyes and dazzles you as well as showing up every single smear and speck of dirt on the windscreen.  You may have to cope with more rain, or even frost and snow, and you may have to cope with darker mornings and evenings.  Of course, this will vary, depending on how far north, south or inland you live.  Accidents become a lot more common.

Even outside winter, the unexpected can happen.  It’s not just accidents that happen, either.  So do breakdowns.  To misquote Eeyore from Winnie-The-Pooh, the thing about accidents is that you never know you’re going to have them until you’re having them.  However, we can be prepared for emergencies – even if all we have to do is to sit tight and wait until the breakdown service arrives (and hopefully not the ambulance and police). 

In these situations, it’s wise to have an emergency kit stashed in your car to help you cope with most situations.  Many car manufacturers will provide you with an emergency triangle and some have a first aid kit as an accessory.  You will probably need more than this to cope with an emergency; however, it’s probably not a good idea to have too big an emergency kit because if you carry too much weight around in your vehicle, you’ll end up reducing your fuel efficiency (and won’t have as much space for luggage as you had hoped when you first bought the car).

What I’d recommend as a good in-car emergency kit to see you through breakdowns and similar emergencies, either rural or urban, would include the following:

• A mobile phone with plenty of charge.  This will allow you to send for help, and most modern phones also include a torch as well, which is handy if it’s dark.  However, you probably carry that with you most of the time anyway.
• A Swiss Army knife and/or multi-tool.  I’ve been mocked for carrying one of these in my handbag – until someone needs a knife or screwdriver.
• A first aid kit. This should contain bandages, sticking plasters of various sizes, antiseptic cream, scissors, tweezers, painkillers (paracetamol, aspirin or ibuprofen) and any medication that you use on a regular basis (e.g., insulin, Epi-pens or antihistamines). Plastic gloves and cotton swabs are also good to include.
• Water.  This can either be for you to stop you from becoming dehydrated, or you can use it to top up a radiator.
• A jacket. If it’s a cold, wet night and you’ve had to turn the engine off (or your EV has run out of battery) in the middle of nowhere, you will need to keep warm somehow.
• A jack and other tyre-changing tools. These usually come with the car.
• A small shovel. You won’t need one of these if the only driving you do is urban or on well-maintained roads. However, if you head out on rural roads or places where things can get a bit rugged, a shovel can really come in handy.
• A fire extinguisher.  If you have an EV, make sure you have the right sort of fire extinguisher, as not every type works on EV battery fires (known as thermal runaway).  These fires, unlike fires in ICE vehicles, don’t require oxygen, so the trick of starving them of oxygen with foam won’t work.
• Snacks. If you get hangry, everything will seem worse, so having something to keep your blood sugar levels topped up while you wait for the breakdown services will keep tempers from running hotter than they already are.  It’s probably best to make sure that these aren’t too sugary, though, to avoid sugar highs or boom-and-bust insulin levels. Think nuts and muesli bars rather than my mother-in-law’s favourite (barley sugars).

Some other items that you could add to your emergency kit could be the following:

• High-viz gear with reflective strips. This is useful if you have to change a tyre in the middle of the night.
• Rope. You may have to tow or be towed at some point.  In the words of JRR Tolkien, “Never travel far without a rope!”.
• Reading material. Sometimes, you may have to wait for the breakdown services for a very long time.  You could use your phone to stop yourself from getting too fidgety, but in an emergency, it’s best to conserve the battery.  Reading the map and/or the driver’s manual gets old very quickly.
• Jumper leads.
• LED torch. Sometimes, your phone is awkward to hold and direct to the right place, or you may not have much charge.
• A strong magnet on a string. This is useful for retrieving bits of steel or iron (e.g., screws, nuts and bolts) that have fallen somewhere awkward.  (In a moment of irony, I was interrupted while writing this article to help the amateur car mechanic in my life do precisely this.)

These items don’t have to be kept all in the same place in your car – you might have the jacket in the boot, the jack with the spare tyre, the muesli bars in the glovebox and the first aid kit under a seat.  Some items might live more or less permanently in your handbag, man bag, briefcase, backpack, jacket pocket or whatever you use to cart about your keys, phone and wallet.

The most important thing in your in-car emergency kit is you, so make sure that you stay alert and use your common sense.  That might help you stay out of an emergency in the first place.

Choosing The Right Driving Posture

When I learned to drive, I wasn’t told much about correct driving posture apart from ensuring that my feet could reach the pedals (obviously) and that my hands were in the “ten past two” position*. However, as time went on and I drove more, I soon came to learn that there’s more to sitting comfortably, and there’s a reason why car manufacturers take so much trouble with designing seats and making them adjustable in many different ways.

If you’ve felt stiff and sore after driving for a long time, then your driving posture might have something do to with it. Sitting down in a car seat is no different from sitting down in an office chair from some perspectives, and it’s important to allow for regular breaks during a long drive so that you can stretch your legs, etc. – just like you would if you were at work. Your office chair is probably not as comfy and cushy as the driver’s seat, unless you’ve done what I’ve done and converted the seat from an old Ford Falcon into an office chair (it’s a pig to move in and out, though, as I haven’t put castors on it).

Although the idea would be to get up every 20 minutes, we all know that this isn’t always possible when driving (every hour is more like it).  However, you can reduce the strain on your body – and it is strain – from holding in one position for ages by ensuring that you’re sitting correctly. If you’ve felt stiff after a long drive, then this might help you.

Everybody’s body is different, so I can’t give precise measurements and angles.  You may have long legs in proportion to your body, a big bum or a long back.  You may be a massive great big dude over six feet tall, or you may be a petite woman reaching five feet in her high heels.  This means that what’s ideal for you probably won’t be idea for someone else.  In fact, what’s best for you might not even be possible in some vehicles, so always test out the seats before you buy a new car.  This means that in the case of a couple consisting of the big dude and the petite lady, you’ll need to compromise (not ideal) or even buy two cars.

OK, to make sure you’re sitting comfortably, let’s begin with some basics. Take your wallet and/or phone and anything else out of your back pocket, because that will have an effect.  Now take time to find out what a neutral spine feels like.  A neutral spine is not a straight back, as the human spine is supposed to have a nice gentle S-bend shape to it.  Stand up and, if you can, check in a mirror side on.  Ensure that your weight is evenly distributed on both feet and don’t fully lock your knees.  Now imagine that there’s a string attached to the top of your head and that it’s pulling you up. 

For more help with knowing what a nice neutral spine feels like, I suggest chatting to your friendly local physiotherapist, taking up Pilates or both.

Now to get into the car.  Oddly, you need to start with the seat in completely the wrong position and then bring it into the right position.  If you’re doing this for the first time in a new car (or a car that you’re considering buying) then move everything as far as it can go – seat angle, steering wheel and all. Push the seat right back as far as it can go.  Now you’re ready to adjust it.

Let’s start with the seat height. In fact, the seat height is the least adjustable thing in many cars, so if you can’t get the height right, you may have to consider another vehicle. Your hips should be about as high as your knees or just a smidge lower (but not too low).  However, you shouldn’t be so high that you hit your head on the top of the car or that you have to crane your head down to see the instrument panel.  If you are too low down, you can use a cushion to get you high enough.  Also check where the edge of the seat is relative to the backs of your knees. If the edge of the seat pushes into your knees, this will restrict your circulation, and riding in that car will be very uncomfortable. Seriously, this matters.  I once owned a car that did this to me. It was great in other ways but the problem with circulation in the feet and legs was so bad that we sold the vehicle (hope it suited the new owner better). Reach down and see if you can fit two fingers between the edge of the seat and your knees. If you can, you’re all good.

Now bring the seat forward so you can reach the pedals (and the footrest) while keeping your back snugly against the seat.  You should have a small bend in your legs, as locking your legs for long periods isn’t all that good for them.  Your heels (in bare feet or ordinary shoes, not high heels) should be on the ground rather than dangling, and you should be able to push the pedal down with your heel on the floor as the fulcrum of a lever.  It’s possible to buy pedal extenders so you can do this if the car is perfect in every other way.  Of all the things that make driving tiring, an accelerator pedal that you can’t operate with your heel on the floor is the worst, and I’ve driven a couple.

If you can adjust the tilt of the seat, play around a bit until you find the position that gives you a neutral spine.  Women will naturally have a more forward tilt than men thanks to the shape of the female pelvis (high heels were invented to exaggerate this) but not too extreme.  Modern car seats have been designed to prevent “submarining”, which is when someone slides out under the seatbelt during the sudden stop in a crash, but this slightly backward angle isn’t all that good for our backs.  There’s not much you can do about this, so get the tilt as close as you can to what gives you a neutral spine.

Now for the seat back. This should not be at right angles to the ground (straight up and down) but it shouldn’t be so far back that it forces you/allows you to slouch your chest, head and shoulders forward.  Keep that spine in neutral position.  If you have lumbar support, this should sit snugly into your lumbar lordosis (the curve in your lower back just above your pelvis).  Some cars don’t have height-adjustable lumbar support (bad luck), and just have lumbar support that’s adjustable in terms of depth.  If your car doesn’t have lumbar support or if it’s in the wrong place for your body (I have a long back in proportion to my legs, so this happens to me a lot), then a lumbar cushion is worth buying and fitting to your car.

Moving on up, make sure that your shoulders can press against the back of the chair, then adjust the head rest. The head rest is supposed to be a head rest, not a neck rest, so sit with a neutral spine and ensure that the head rest touches the back of your head.

Now to adjust the steering wheel. You should be able to get both hands on it with a slight bend in your elbows – driving with straight arms puts strain on your shoulders and neck.  The best position isn’t “ten to two”, as I was taught, but quarter past nine (nine and three) down to seven and five.  Adjust the height of the steering wheel to suit you.

In a perfect world, we’d be able to customize everything so that it suited our bodies perfectly, especially when it comes to female bodies. Traditionally, car seats have been designed to fit the average male, but manufacturers have seem to have woken up to the fact that half of the population has a female body and are factoring this into their seat designs and safety features (Mazda and Volvo, for example).  That’s a topic for another day (and one I’ve discussed before) but in the meantime, if you aim to have a neutral spine and to keep a gentle bend in your arms and your legs while driving, you should be about right.

And don’t forget to allow for regular breaks to get up out of your seat during a longer journey.