Water Entered Home Through P-Trap Hole in Slab

I live in North Texas. Last weekend we received a large amount of rain. I returned to my master bath from a weekend away to find a mixture of water, dirt & silt everywhere in my bathroom. All of the tubs and showers in the house showed evidence of having water backed up into them through the respective drains but, this water was contained. I also had the water, dirt & silt on the floor. I have traced this back to the p-trap hole in my slab. Now here is my question. The hole was put in the slab for a garden tub that has a bottom drain on it and the tub is set on the top of my slab. I understand the need for the hole in the slab. How can I minimize my risk of having water come up through this hole yet again the next time a heavy rain falls? Any & all suggestions would be welcomed!

rain

I know you had a lot of rain

Given those conditions, water always wins...........

You could plug the trap with an expanding plug or some other kind that will fit.

But the bigger question is, what is the other end of it connected to. Is it supposed to go to the septic system? It looks like you have a septic system that got flooded. You would probably have had a tough time flushing the toilet or taking a shower.

You may need to do something to keep the surface water away from your leach field.

Another thought on the flooding and backflow:

You should not be getting silt and dirt back from the septic system, since the septic tank is a pretty good trap to collect silt.

Is it possible that the P-trap designed for a garden tub was at a low point which could have collected flood water?

Also, there might be a failure in the drain between the house and the septic tank that collected water and flowed it back to the house.

In any case, your leach field must have been flooded because it is lower than any drain in your house.