Floodwaters affect a house in three different ways:
Dampness promotes the growth of mildew, molds, or fungus that grow on everything.
Mud, silt, and unknown contaminants in the water not only get everything dirty, they are also are very unhealthy.
Water damages materials. Wallboard will disintegrate if it stays wet too long; wood can swell, warp, or rot and electrical parts can short out, malfunction, and cause fires or shock.
Actions to Take in Drying Out Your Home
Air out the house to lower the humidity. If the weather permits, open doors and windows to increase ventilation. Open closet and cabinet doors. Use fans and run dehumidifiers. Drain the ceilings and walls. Dry the ceilings, walls, and floors.
Because of the risk of serious illness, throw out water-soaked:
Sort contents and discard debris. You will usually want to throw out floodwater-soaked:
Upholstered couches and chairs
Heirlooms and valuable books and papers may require special treatment.
Use products like kitty litter, chemical dehumidifier packs used for drying boats and damp closets, and calcium chloride pellets to remove moisture.
Call a contractor for estimates of work that you can't do on your own.