The most efficient way to keep your house from being ruined by floods is to have basically a "house on stilts". Just like the hurricane proof homes, this type of building or structure is raised up on poles that are able to hold up the weight of the house. Most houses already have these and the usually get made into basements, so all you have to do to make this happen is make those "stilts" stick out of the ground. Concrete is one of the more common materials to be used for this purpose, but you can use other materials.
Scientists are also working on creating a house that will float. This house is very effective at staying out of floods, but can not have a basement. This house is also able to keep the people and things inside safe and balanced. When the house rises up with the water the power lines and pipes that are normally connected to the house detach and reconnect easily. There is also a back up power, sewage, and water systems are designed into the house, but can be removed if wanted.