Over the last 3 years we have hade 3 major rain storms... each time my basement floods with clean water that comes out of the toilet... I have a check valve that does not allow raw sewerage to come into the house... someone told me about buying a toilet bowl bullet or plug that would not allow the drain water to come up from the basement toilet. Anyone ever heard of this and where would I purchase one? What exactly is it called & does it work? Jo

If your weeping tiles are connected to the sanitary sewer and the system is overloaded in a heavy rain the water will come up in the lowest connection in your house.
The check valve will stop sewage from coming into the house if the main on the street backs up but if that check valve closes there is nowhere for the drainage water from your own house to go.
The answer is to redirect the rainwater away from the sewer.
This usually means running the weeping tiles to a sump hole and have a sump pump take it away.
Direct the roof leaders away from the house as well.
Check with the sewer authority in your area. Overloading the sewers has become a major problem in many areas. Many are offering subsidies to complete the work.

To answer your question if you plug water from coming up in one spot it will find another entry point. So it is better to fix the problem then to try and address the symptoms.