Soakaway depth digging... 3.5m When can I give up? :)

[DaveSpud47]

Hi guys,

Digging a soakaway, initially dug to 2.5 meters deep - but after a month of testing it was not draining at all.

Clay layer seems to go on forever, we have a hilly field to the side of the soakaway - theres lots of red clay very old land drain pipes which run across our property a few feet under the surface - presumably due to the bad drainage of the soil?

I have now managed to reach 3.5 meters deep, I had to dig out a pad for the digger to sit lower to reach this depth- however it still seems to be clay, the water still seems to be sitting in the bottom. I realise I need to reach the porous layer after the clay, but at what point do I give up, this seems insanely deep ? is this normal?

I read exceptions can be made if a soakway is not feasible the normal drain can be used - the waterboard require an additional payment per month for the extra run off water...?

 

[oldbutnotdead]

Building Control can make that call. LABC tend to know their local ground conditions & would have advised up front that a soakaway wouldn't work.
Check your water bill, it should tell you if you are already being charged for surface water disposal.

 

[bernardgreen]

theres lots of red clay very old land drain pipes which run across our property

They might run towards an area of land that will allow water to soak away,

 

[denso13]

I have now managed to reach 3.5 meters deep

Deeper usually means firmer/worse for draining. Might be time to look for a different solution.

 

[DetlefSchmitz]

Just to mention my son's recent experience. They had to provide a new soak-away on the front drive and the builder duly dug down with a jcb. There was still clay and celebrated their new pond.
The plans for the highway outside (don't know how they found them) seemed to indicate that there was gravel somewhere below the clay. They got two quotes, one for a bole hole (several thousand pounds), and one for a jcb with a drill attachment. After a quarter of an hour with the drill attachment all the water in the hole suddenly disappeared.
I would say that the decision to drill was taken using the local area survey knowledge, so if any such intelligence is available it is worth asking.

 

[Hugh Jaleak]

Crikey, most would have given up long before.

if you're on clay soil, a soakaway is never likely to work well, if at all. Building Control should be aware of this and accept alternative solutions. Surface water sewer would be the next option, if that isn't available, then connection to a combined sewer would be permitted as a last resort. Water Company will charge you for Rainwater disposal though if connecting to their sewer directly or indirectly.