I met one lady who opened her closet to have two snakes fall off the closet shelf in front of her. Carbon monoxide exhaust kills. Do not use generators or other gosoline-powered machines indoors. All cooking on camp stoves and charcoal grills should be done outside. Drain the basement carefully and slowly.
Ground water creates hydrostatic pressure on basement walls and floors.
Drain the basement no more than one foot per day to minimize further structural damage. Hose the house. Many health hazards are found in mud and silt which fllodwaters leave behind. Shovel as much mud as possible out of the house, then hose it down, inside and out. Be aware of health hazards.