I've just had a new patio built. Unfortunately the landscaping done by the company's recommended concretor wasn't any good, and I've got water pooling about the side of the slab which is 12m long. We want to drive the car under the patio, so I've had to stack some wood to drive in as the shaping of the bank isn't any chop either. I'm not interested in getting them back as they did a crap job, so I'm going to sort it myself.
Anyway, I need to look at solutions. I was originally thinking channel and grate, but the slab directly adjoins a bank, and there's water not only on the surface, but beneath the ground that I feel I need to address as it will be getting under the slab. I'd then have to concrete that in, and although the plastic stuff is cheap, prefab concrete channel and grate is over $5k for 12m's. That said, I'm now thinking a 100mm socked and slotted agi pipe gravel drain is the way to go, as it would cost much less and I wouldn't have to concrete it in. I think the bank need be shaped back with the loader a bit to make it less steep so I can drive the car on, and I'll put some black matting on it to stabilise the dirt to stop it sliding down into the drain. I might also get a prefab concrete channel and grate for the section the car will drive over and concrete it in, or use a culvert.
My question is now about how to do it. I've attached a photograph so you can see the situation.
I thought I could either:-
1. Scoop out dirt with the backhoe parked at a right angle to the trench and then try and neaten the cut with the loader bucket. I've got a 16" backhoe bucket and an 8", but this would a long time and the result mightn't be very tidy. I'd like a neat trench if I can.
2. Just try and scoop it out with the loader. This might work as the ground is soft muddy and soft, but I can see I'll have to do some pick and shovel work as I might not be able to get close enough to the slab.
3. Try and use the backhoe along the side of the concrete with half the tractor on the slab and the other side on the bank. My main concern with this is how I would deploy the stabilisers on the bank, and slab. The ground is very soft, so perhaps I wouldn't need to fully take the weight of the tractor with the stabilisers, not sure. I think this would be the neatest and quickest way. I could probably put something under the stabiliser on the slab so it didn't damage the concrete.
I thought I would dig the trench down about 1ft alongside the slab so I could capture the ground water and surface water beneath the level of the slab, and then fill the trench with rock to the level of the slab. I thought I'd make the trench about 1.5ft wide. I'm not sure if I should just put two agi pipes in the trench or if one is enough.
I'm just a bit concerned about the stability of the tractor using option 3, but it would probably be the best way and do the neatest job in the quickest time. I think the other options might give me mixed results or require more pick and shovel work to make it tidy.
I thought I'd put a pit drain with a grate on top at either end so I can clean out the agi pipe. From that pit drain I thought I'd run out under the fence into the paddock with solid 100mm pipe, which will be a 22m run. Fortunately I've got plenty of fall one I get past the slab I slab so I can put the agi pipe and solid pipe in at whatever depth I need to get enough fall.
I really didn't want to pay for someone to come in and do the work, as I know a digger would just run alongside the slab and sort it out, but I've got a tractor to use and I'm keen to get more seat time.
I'd appreciate any input as to the way to go. I'm sure there's some collective wisdom here I can tap in on.
Thanks very much.