Shaun Eli wrote in news:d831bad1-f05e-
:

Just to clarify, it's a drain at the bottom of the outside steps to
the basement, not a sewer drain (the water just goes into the ground,
or comes from the ground).

I know it's a water-table issue since other things at the same level,
such as neighbors' yards, flood in extreme rainstorms.

I'll try installing the one-way valve. Thanks,


The valve should be fine for your application but if it is closed due to a
backflow then no water can get in either. Do you ever get a situation where
the valve is closed but it is still raining? Where would your runoff go
then? Can you tolerate a puddle for a while that would drain away when the
groundwater receded? Note that if it is truly groundwater rising then the
time frames are much longer than rises in sewers - measured in many hours
or even days.

Do you think you should be considering a sump pump? It would require some
digging and concreting but you say you may need that anyway?