When Flooded, Turn Around! Don’t Drown!

It has been a furious monsoon so far . . .

In view of the recent flood situation triggered by stormy rains, the Health, Safety, Security, and Environment (HSSE) department of my office circulated an email today on staying safe with our vehicles on flooded roads. I would like to share points of the same so that it can be useful for a larger audience :

Photo Credit : hotblacktop.com

As with all driving emergencies prevention is better than cure; in the case of flooding this means watching the weather forecasts before you set out on a journey. If flooding is widespread you might be better off canceling trips that are not absolutely necessary.

Points to consider…

  • Flash floods can come rapidly and unexpectedly. The main causes are when rivers break their banks or when there is torrential rain.
  • You may not receive any warning that a flash flood is approaching.
  • If the water is too deep to walk through then, do not attempt to drive through it – this is a good measure and gauge to determine if it is safe to drive.
  • Floods hide dips on the roads, deep potholes, etc. Worse still, flooding can wash away the entire road surface and a significant amount of ground beneath.
  • Just six inches of water will reach the bottom of most passenger cars; this depth can cause loss of control or possible stalling as water is sucked into the exhaust or run into the air intake.
  • If you have to drive through a flooded section of road, drive in the middle, because normally water will be at its shallowest in the centre of the road.
  • Consider other drivers – pass through flooded sections one car at a time, don’t drive through water against approaching vehicles.
  • Many cars will start to float in as little as one foot of water – this can be extremely dangerous because as the wheels lose grip, you lose control.
  • Two feet of flowing water can sweep away most vehicles — including large 4 x 4s. Don’t try driving through fast-moving water, for example approaching a flooded bridge – your car could easily be swept away.

Stay Safe

Negotiating floods

  • Driving at speed into water that is more than 6-8 inches deep can have serious results – it could almost feel like driving into a brick wall with loss of control. This is why it’s especially important to watch your speed on roads where there might be unexpected patches of water (perhaps hidden by a bend or a dip in the road).
  • If you intend to drive through a flooded section of road, your first task is to check the depth of the water. In normal vehicles you should never attempt to drive through water that is more than about 8 inches deep (or up to the centre of your wheels).
  • It’s also worth checking where the air intake is on your engine. If water is sucked into the engine it will stall, but worse than this, it can cause severe damage that will require the engine to be stripped down in order to bring it back to life. Do not try to restart an engine that has sucked in water – the plugs or injectors should first be removed to allow the water to be expelled.
  • Using your first or second gear (L or 1 in an automatic), drive slowly to avoid creating a large ‘bow wave’ (a small wave can be helpful but too much and the water can wash back into the engine). Slipping the clutch and revving the engine will also help to keep the exhaust clear and keep the engine running if water splashes onto the electrics. In an automatic keep your foot on the gas in the lowest held gear and use the brake to control your speed.
  • In some cases a stalled engine can result in water being sucked back through the exhaust into the cylinders – this can cause extensive and expensive damage. Do not changes gear because this can also cause water to be sucked back through the exhaust (due to the change in engine speed and manifold depression).
  • After driving through a flooded section of road, test your brakes (whilst still driving slowly) and dry them off by touching the brake pedal very lightly
  • If your car has been abandoned and has stood in deep water for a long period (an hour or more) it’s worth getting a mechanic to look at it before you try to start it.

Above all, stay safe! 🙂


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s