When there is a lot of rain, water backs up in my basement through the drain pipe. I have heard that there is a ball-type closure for these drains that will let water flow out but not back in again. I would like to know what it is called, where it can be found, and how to install it. Thank you.
There is. It's called a floodgaurd. It is a check valve that screws into a floor drain and stops the water if the drain backs up. C.