Drainage Soakaway in Courtyard of 300 Year Old Limestone Cottage Drainage pipes, concrete, footings and foundations. Post your questions and find answers here

[CathrynM]

Hi. I have a 300 year old limestone cottage. My garden is a small stone courtyard. Enormous random stone slabs concreted in. (Going for artificial grass when drainage is sorted.) It has a small earth border on one side, alongside a low stone wall and raised flower bed, which borders a field at about 3' high. The main drainage is what appears to be a soakaway in one corner. About a foot away from next door's house wall and about 6 foot away from my house. It is blocked and has been flooding in heavy rain. On investigation I find there is a drainage hopper with a pipe about 12" long and then just mud and stones beneath. The ground here is incredibly stony. I have cleared out as far down as I can reach. I can poke a long garden cane right down in one corner of the drain, but the water is still sitting in the pipe at about 13" below the ground level. This is the first time I've had a problem with it in the 7 years I've been here. Can anyone advise please?

[welsh brickie]

I assume that the pipe has been blocked over the years with roots and soil debris,
The only way is to have it dug out and replaced, or have a large soakaway pit, lined with weed control fabric, and filled with soakaway boxes. And re route the drainage pipes to it

[CathrynM]

Thanks, welsh brickie. Thing is there aren't any pipes. Just the drain hopper and then nothing. Digging it out would be a nightmare... there is enough space for a spade but no more than that. Would that be sufficient? These are extremely heavy stone slabs, i would worry for the stability of next door's wall just inches away and with some crumbly stone blocks in it, if drilling etc went on... and there is no access to the courtyard save through my sitting room. I am wondering just what sort of drainage system they would have used, 300 years ago? And what is a safe level for the water to be sitting at? I am near the top of a slope (hence the raised border). I know nothing about this sort of thing. Need some info before calling someone out.