Even though a basement dehumidifier can be extremely effective when handling the dampness left behind after your basement floods, it shouldn’t be the only way you try to fix flooding in your basement.
A basement dehumidifier doesn’t actively address the physical presence of water in your basement. That’s what an interior drainage system and sump pump are for. The drains collect perimeter leaks and direct the water to a sump pump. The sump pump then pumps the water out of your basement and away from your home.
You can then address water vapor or humidity with a wall vapor barrier and a dehumidifier.