Flooding can cause damage to carpet that you cannot see, but that may affect your long-term health. Much depends on the kind of water that flooded your carpet as to whether you can clean it or must replace it. Time is of the essence when dealing with a wet carpet.
Sanitary water is water that does not contain contaminants. An example of this is having a water pipe break underneath a sink, flooding your home. While some experts advise removing your carpet no matter what has flooded it, usually this type of carpet flooding can be cleaned and disinfected effectively. The key is to have a professional remove the water as quickly as possible and disinfect the carpet afterwards. Try not to walk on the carpet before the water is extracted, because you can weaken the latex bond that holds your backing to your carpet. The carpet will likely need to be pulled up from the tack strips and the padding underneath should be removed, since it can harbor mold even after being dried. Depending on the extent of flooding, your carpet cleaner may elevate the carpet and use fans and dehumidifiers to remove as much moisture as quickly as possible.
Unsanitary water contains contaminants that can be harmful to human health, such as that from a toilet or dishwasher overflow. Some professionals recommend discarding contaminated carpet, but if you can remove the water quickly, you may be able to save it. A deep disinfection needs to be done by a professional, who will later test the carpet to see if this was effective. If potentially harmful contaminants, such as bacteria and mold, are still present, the carpet should be discarded, and the padding should always be discarded and replaced.
Black water contains raw sewage or has been in contact with the ground, such as water from a storm flood or an overflowing river. There is no way to salvage carpet contaminated with black water without seriously endangering your health and that of your family. The carpet, padding and tack strips must be removed and discarded.
You should not try to clean a water-flooded carpet yourself. Machines available to homeowners are not strong enough to remove all the water, and the water left behind will lead to mold and bacterial contamination that can harm you and your family. Always call a professional as soon as you discover the flood and have the water removed and carpets dried as quickly as possible.