Drainage Trench/Soak Away

[Andehh]

I am half way through building my decking, and due to my garden being like modelling clay from 2" under the surface, and surrounded by houses, AND being the lowest point in the surrounding area it tends to be very damp.

Half way through doing my decking, i dug a hole 1.5 feet wide, by 4 feet long by around 2 feet deep. Idea being it would drain most of the surface water away and then it would seep out the hole in between rain. (for 70% of the rain we get).

With all the higher then average rain we have had over the last few weeks the hole is totally full, and surrounding area is as wet and boggy as ever - before I have out anything int he hole hardcore wise.

Now I know it doesn't make a great soak away, as the water seeps out slowly due to the clay soil and it isnt big enough to handle ALL the water, but as a way of handling medium rain fall, and it stop it puddling under the decking would it be alright?


My main concern is also how far away it is from the 4 deck posts, concreted into the ground. I will fill the hole full of 10mm gravel, but I am worried that over time the mud will still move away from the posts into the hole/displacing the gravel.

Is this something that might happen in heavy clay soil?

Hole in question with deck supports/joists.
http://dl.dropbox.com/u/72120595/Hole.jpg

 

[Andehh]

Can anyone comment on whether the gravel will support the soil, or will the clay soil still desperate from the concreted posts?

Thanks

 

[Andehh]

One last attempt for advice!

If in doubt I will probably fill the whole thing with gravel, and hope that it helps with medium-light rain and draining the surface of it and accept that heavy like we are having at the minute will be hopeless either!

 

[freddiemercurystwin]

Soakaways do not work in clay end of story. It will only drain in a drought and there wouldn't be any need for it then anyway. You may as well fill it back up with clay.

 

[jdpjamesp]

Edit: Talking from my rear end...

 

[Andehh]

damn, ok then! I will fill it half in and then fill the rest with gravel, he extra surface area might help evaporation a bit! thanks

 

[lachesis]

Hiya mate

Bit late but I had exactly the same problem and in the end fitted one of these into the sump:

http://www.amazon.co.uk/dp/B0011NMJ...d=13920284022127633857&hvpone=&hvptwo=&hvqmt=

Works a treat. The float switch activates the pump when sump is full and then auto cuts off when it reaches a low level.

You'll need some 2.5mm flexi hose from your garden centre and a hose clip as well.