Robin Wilton's esoterica

Apologies to non-UK readers... this is not going to be very relevant to you today... but just in case anyone in the affected areas sees this today, here goes.

We've had a very wet few days here, and the combination of bad weather and heavy traffic is going to make for some nasty journeys (just about everyone is back at work now following the holiday break, so Friday afternoon traffic is at or near its peak). Around here, the rain is hovering on the brink of turning into sleet.

Locally (West Wiltshire/Kennet Districts) I've encountered several stretches of deeply flooded road, so if you're using the A350 in particular, take care.

Having learned some grim lessons from our experiences back in July, here are my tips for driving in flood conditions (other than the obvious one of 'don't if you don't have to'!).

1. Be on the lookout for flooded road. If others have reached a flooded section ahead of you, expect queues of stationary traffic in unexpected places. If you are not in a line of moving traffic, watch out for standing water: if you hit it at speed it may end your journey*.
2. Even if the road is only partially flooded, slow down and take care. If a truck hits standing water on the other side of the road, you may get a catastrophic amount of water dumped on your vehicle. In the Great Scheme of Things, it's far better to slow down and wait until oncoming traffic has cleared the water.
3. Be patient. If you're in a line of traffic going through a flooded stretch, my advice is to wait for the vehicle ahead to clear the water before you start in on it. People behind you may get impatient, but I'm sure they'd rather be stationary on 'dry' road than in the middle of 100 yards of water...
   
4. Similarly, if there's two-way traffic through a flood, take your time. Oncoming cars may well take to the centre of the road in order to drive through the shallowest part.

*Specifically (again, from what we learned in the 'summer'): if you hit deep water at speed there are several risks.

• There's aquaplaning; even comparatively shallow water can exceed your tyres' ability to displace it, and when that happens, the only thing the tyre can do is detach from the road surface. Your car was not designed to steer/stop when floating.
• A 'bow wave' from the tyres can spray up under the car and reach electrical components;
• Worse, if the water is deep enough to reach the front bodywork of your vehicle, a far more substantial bow wave can build up, and quickly be sufficient to detach bits of bodywork. If this kind of bow wave gets at the engine compartment it can do all kinds of damage. The impact can damage components like oil coolers and detach hoses/cables. If a large quantity of cold water gets dumped on a hot engine, you can end up with a cracked block. Expensive.
• What you're driving through may not be just water. In our case in July, the water picked up a rock and threw it at the oil cooler, which punctured - emptying the engine of oil. Fortunately the warning lights came on, so the engine wasn't damaged; it could have been worse, but it was quite bad enough.
• Once you're through the water, gently exercise your brakes until you're confident that they aren't soggy. Remember, you may have to use them at short notice before this journey is finished.