water coming through walls from void under surrounding porches
New home not moved into yet. We are in south with huge rains. Walkout basement with french drains that worked until the got clogged as we did not extend them long enough to clear construction dirt buildup. Result is water seeping through basement walls. We built usingcinder blocks, filled with rebar steel and filled with concrete. we put moisture proof sealer on walls interior and had painted 2 coates of ames saterproof sealer on exterior plus a foam board to keep rock from damaging wall sealant before we backfilled with rocks then sand. We sustained 20 inches of rain in 24 hours. Basement loked great until 6 hours later, water built up and could not get out. We dug up and found drains, cleaned and water gushed out. Guess the trouble of backfilling with rock and sand was good idea as it is getting to french drain, just blocked. So I know it will work but problem is much greater. We built 8' x 60' concrete porch on back side of house above basement that is underground theinking that water will never get in there...wrong. We have exposed soil which is sandy-clay, mostly clay. They graded and were ready to put grass down. Well, we left a 2' x 2' hole in two areas inf ront of porch for plumber to put cut-off valves for us where water lines enter home. Rain came first. It filled holes with water then pushed through under concrete porches and left huge voids under. Rain came again and now continued to make void under attached garage that attaches to one corner of basement. Now water is running around corner and lying in large hole against house. How do you fill these voids, we cannot reach them. Will anything last or will it continue to happen? Will that bentonite stuff work? Any ideas would be very much appreciated. No one has basements in the south, guess we know why now.