RAC Know-How

Driving in floods

If you live in an area where flooding may occur, move your vehicle to higher ground if flooding is expected. As well as the risk of damage to your vehicle by leaving it in a flooded area, it may also be a hazard or cause obstruction to emergency services.

Tips for driving in flood conditions

• Do not drive unless your journey is absolutely necessary.
• Plan your journey to avoid flooded areas and make sure you allow plenty of time. Listen to local media broadcasts or call RAC's Traffic and Travel Service from a land line on 0906 470 1740 or 1740 from any mobile phone.
• Take spare dry clothing, food, a flask of hot drink and if you have a mobile phone make sure you have the telephone number for contacting the emergency services.
• If you have to drive in a flooded area take care. Do not attempt to drive through water if you are unsure of the depth.
• Other than potential damage to your vehicle, many vehicles require only two feet of water before they float.
• On some vehicles the level of water where damage may be likely is only a few inches deep.
• Serious engine damage may occur if water is "sucked up" into the engine air intake system.
• Modern vehicles are fitted with catalytic converters in the exhaust system. The catalyst normally works at high temperatures and may crack if it is submerged in water. Replacement catalysts are expensive.
• If you have to drive through a flood try to drive in the highest section of the road if it is safe to do so.
• Drive only fast enough to create a small bow wave in front of the vehicle. Driving at speed may be dangerous to other vehicles or pedestrians.
• Do not drive through flood water if a vehicle is travelling in the opposite direction.
• Test your brakes thoroughly after leaving the flood water.

If your car is flood damaged

Depending on the level of water which affected your vehicle the following precautions should be taken:

• If the level of flooding has entered the passenger compartments (wet carpets) and the vehicle is fitted with an airbag, do not turn the ignition on. It is important to have the vehicle professionally examined (there is a risk of airbag deployment from water in the electrical system).
• If the vehicle is not fitted with airbags, there may still be a risk of electrical short circuit which can cause further damage to your vehicle. Again, do not turn the ignition on and have the vehicle professionally examined.
• For vehicles where flooding has not entered the passenger area (dry carpets) the braking system of your vehicle may have been affected.
• If the vehicle has been stood in the flooded area for any prolonged period contact your local dealer for further advice.
• If the vehicle has only been in a flood for a short period, drive with extreme caution and take the car to be checked at the earliest opportunity.

Author(s)
RAC Public Relations