The Brew Cabin

I am looking to replace my concrete slab driveway with gravel. My worry is about where the surface water will go, as there are cellars the length of the driveway. at present all water runs away from the house to a central grid and drain which runs down the centre, the length of the driveway. How do I ensure the water does not seep through the gravel and cause damp in the cellar walls which are below the level of the drive.

You're imagining a problem that doesn't exist, Malcolm. The earth against the cellar walls at this moment is 'damp': just because you have a concrete 'cap' over the top doesn't prevent groundwater naturally spreading by capillary action and hydrostatic pressure.

Precipitation enters the groudn to the edge of your concrete and then seeps in and under, eventually finding its way to the cellar walls. If you remove the concrete cap, then the water may be able to get to the cellar walls a little bit quicker, but you're not increasing any risk. If you're really, really concerned, then you'd need to line the external face of the cellar walls with tanking or a membrane, which would be fantastically expensive!

When you rip up the concrete, lay a length or two of land drain in the sub-base, and connect them/it to the existing SW system and that will act to channel away any excessive flow of water. :)

Sounds good! Next issue is where can I find a specification for laying a typical gravel drive. Eg construction of sub base, depth etc to ensure it is not like driving thru a field after a few months!

Err..maybe on the Gravel page, perhaps? ;)

Very true!