Tidal Water flooding on drive due to soakaway.

[Corazones]

I had a vaguely similar experience to Davey's although we live nowhere near the coast. Our drive also slopes towards the house and occasionally floods from surface water. We had a full width storm grille installed across the bottom of the drive and this water was piped through into our main 2cu.m.soakaway in the back garden. Then the problem became worse because under heavy rainfall the water backed up and came out in reverse through that grille! The problem was found to be that the soakaway filled up and then the rain built up inside the downpipes. This head was sufficient to send it back to the grille. As this only happens occasionally, I resolved it by drilling a 10mm hole near the bottom of the downpipes and pushing in short stub pipes so that the flow of normal rainfall was unaffected. Excess pressure was relieved and, so far, no more backflow.

 

[Doggit]

This is possibly a daft idea, but what about putting some dpm in the hole, and then backfilling and compacting.

 

[John D v2.0]

I was thinking that too, might need to put it round the sides as well! Or even fill it with 6 inches of concrete before back filling!!

 

[Doggit]

I didn't think that part of it needed explaining, but the concrete at the bottoms a good touch.

 

[Ian H]

If the clay is soggy you might be as well laying a sheet of visqueen over the top and compacting the lot at once.

 

[endecotp]

perhaps you should be "puddling" the clay into the bottom of the hole, like they do in canals.

 

[Daveyp1471]

Thank you all for your suggestions, im waiting for the tides to drop a bit so I get a few days grace as at the moment its just too wet.

 

[motorbiking]

I'm curious, but surely this tidal water is damaging your foundations?

 

[Daveyp1471]

There has always been water under the floor but it moves away pretty quick. It's present on around 300 houses along our road. Thankfully they are well raised with plenty of crawl space under the floorboards. The house is 100 years old and I'm told this would have been an issue back then also and so it's nothing new. The water just didn't cover the drive until I dug the hole but it's a good few feet below the air bricks etc