On Mon, 2 Aug 2010 16:41:54 +0100, "Phil L"
wrote:

IME it's not worth a carrot in terms of draining ground, and certainly
useless as a soakaway, it does have an effect over large areas like farmers
feilds in reducing waterlogging, but far more effective would be 2 milk
crates wrapped in weed membrane and surrounded in 3/4 stone, with a gulley
into the top - a soakaway is just a holding tank, designed to hold flood
water until the surrounding ground can take it away naturally.

Wouldn't it depend how much you used? If you had a large coil running
up and across and down almost following the fences around your garden,
wouldn't that cover a big enough area to drain the rain from the roof
of the house?

TIA