When the river near my house floods the sewer backs up through the toilet and shower drain. Can I stop this somehow? The river water doesn't always come into the house. :(

When the river near my house floods the sewer backs up through the toilet and shower drain. Can I stop this somehow?? The river water doesn,t always come into the house. :(
You have a septic tank, yes? They make a sewer line check valve,(see image) for just your problem. Check with your local plumbing supplier. Good luck and thank you for rating my answer. Tom