We've found out that a house that we're interested in buying has a soak away in the back garden for surface water. Is this usual for a suburban house and what do we need to be wary of or look further into?
Connected to the guttering it should be 5m away from the house, draining into a bed of gravel. I guess as it's clay soil it might be slow draining so the surveyor would look for evidence it is insufficient but AFAIK this is the main approved method for draining water (running into drains requires approval from water authority I believe). Is there a specific reason you are concerned?
I'd just never really heard of it before - I thought most houses (in suburban areas anyway) were connected to the mains drainage for surface water and foul drainage and just wanted to know if there were any things to watch out for and whether this was an usual state of affairs.
If you get a chance to view in the rain (likely just now I suppose!) you can check the guttering and whether the soakaway seem to be coping OK (ie not overflowing which might indicate blockages). As far as I know unless your n a very built up area the preference is soakaways and you have to argue a case to run gutter water into a drain.