Author Topic: Overflowing soakaway (Read 9017 times)

spandit · « **on:** December 22, 2013, 05:17:36 pm »

Noticed the grass next to my barn was covered in water and that it was coming from a nearby manhole. Lifted it and saw that the soakaway was full up. I put a pump in there and fortunately had enough hose to reach a different manhole which drains down to the road. I reckon the capacity is around 3,000 litres and despite the amount pouring in, managed to get it more or less empty. Overnight, it filled up and started overflowing again. Not sure if the ground is just too saturated to allow the water to soak away properly or whether the accumulated silt is the problem

What's likely to be at the bottom of the soakaway? It's a big concrete "bottle" with metal steps in the side. If I could agitate the silt effectively, my pump would probably handle it, but a bit loath to climb down there as don't know how deep the silt layer is. Is this the kind of thing that a drain company could cope with and how expensive is it likely to be?

marka · « **Reply #1 on:** December 22, 2013, 05:22:43 pm »

I know its not quite the same but we had our septic tank pumped out recently - not sure what the capacity is but it cost us just over £200.

Regards

Mark

spandit · « **Reply #2 on:** December 22, 2013, 05:25:17 pm »

Thanks, Mark, I'd imagine it's a similar process, just removing solids. I'm surprised there is no overflow to our soakaway as it's not that far from a proper drain. It was one of the reasons for pumping it out as I thought there would be one that I couldn't see but no

doganjo · « **Reply #3 on:** December 22, 2013, 05:30:22 pm »

Should there not be large stones on the bottom of a soakaway? Mine had boulders in it from clearing the site for building - makes for great drainage. A septic tank doesn't obviously but a soakaway shouldn't need emptying should it?

shygirl · « **Reply #4 on:** December 22, 2013, 07:29:52 pm »

when our septic tankwas full and overflowing it was because someone had built it wrong, and literally put it together upside down so the solids clogged up the lliquid drainage pipe.
how long have you been living there?
scottish water emptied ours for about £200 but it will fill up again within days if you are using the bath/washing machines etc, and the blockage is not solved.

farmer/drainage contractors are much cheaper than the drain devil type of people, by far.

henchard · « **Reply #5 on:** December 22, 2013, 07:47:21 pm »

There seems to be a lot of confusion as to what this is but it's almost certainly not a soakaway. Is it waste water drainage from a property? If so it sounds like it is a septic tank or cess pool. If could be that the land drains are silted up but more likely if your ground is waterlogged the pipes to it are not water tight and are just admitting water.

In any event do not enter it under any circumstances as there can be a build up of fumes. It is also technically illegal for anyone other than a licensed contractor to empty it. If this is waste water drainage from a property it should be properly rectified.

shygirl · « **Reply #6 on:** December 22, 2013, 08:07:32 pm »

it sounds like the septic tank/holding tank prior to the soakaway. when our tank was empty if was actually really deep. i wouldnt ever go in it, what a death, drowned in poop

stay safe

spandit · « **Reply #7 on:** December 22, 2013, 08:18:09 pm »

It handles rainwater coming off the barn roof, that's it. Actually, it's off half the barn roof, no effluent. It's uphill and 100m away from the house.

As far as I can tell, there is one inlet, which is right at the top and easy to access at the other end. The top of the silt is about 7' down but don't know how deep it goes. I'll try poking something a little more rigid down there to see.

There are no outlets, at least, not that I can see (and I've drained it down to about 4" of water, when the pump float falls). The drain I'm pumping it into is about 2' down below the top of the soakaway

Wendelspanswick · « **Reply #8 on:** December 23, 2013, 08:24:03 am »

In that case it's a rainwater catchment tank, not a soakaway, a soakaway is a network of porous pipes downstream of a septic tank.
Rainwater tanks are supposed to be built from porous materials and back filled externally with clean stone, sounds like your ground is water logged and it's either backfilling or not coping with the volume from the roofs.

spandit · « **Reply #9 on:** December 23, 2013, 11:04:42 am »

There is a technique where they put a large concrete chamber in the ground but drill down from it into porous bedrock - wondered whether that's been done here. Doesn't look porous, it's solid concrete but maybe under the silt it's open.

I suspect it's because the ground is saturated as you say. I might look into cutting a hole in the side and running an overflow into the drains

doganjo · « **Reply #10 on:** December 23, 2013, 11:47:32 am »

Can you do that? I thought sewage and rainwater/foul water had to be kept separate? Although to be honest i don't really know why.

spandit · « **Reply #11 on:** December 23, 2013, 01:48:01 pm »

Quote from: doganjo on December 23, 2013, 11:47:32 am

Can you do that? I thought sewage and rainwater/foul water had to be kept separate? Although to be honest i don't really know why.

No sewage involved. When I said "drains" I meant the pipe that takes my ditch from above the house down to the ditch on the road. In between it is buried underground but only rainwater that flows through it (or ground drainage water)