When your basement floods, the first thing you should do is secure everyone's safety by cutting off the power to the affected area, only if it is safe to do so. Avoid accessing the basement until you're certain there are no electrical hazards or structural damage. Once safe, determine the cause of the flooding, which could be excessive rainfall, a burst pipe, or a sewage backup. If water is still entering the basement, stop it as soon as possible and contact a professional water damage restoration firm. Acting quickly can assist to limit damage, avoid mould growth, and save you time and money in the long term.