Explanation

"You should always assess the depth of the water and avoid driving through deep or fast-flowing water. There's a risk that water may stop the engine if it enters the combustion chamber via the air intake, obstructs the exhaust pipe or short-circuits the ignition system. In addition, there's a risk of the vehicle being swept away by fast-flowing water. To drive through shallow water, you should drive slowly, because this will prevent a wave from washing over the engine. To ensure the exhaust pipe doesn't become flooded, the engine speed should be kept high, which may require you to slip the clutch."