French drain or re-contour field?

[chuckey]

I have a pigsty that is attached to a barn. Both are built with rock and rubble and back onto a sloping field. The problem is that the gradient is not constant and a large puddle builds up behind the centre of the pigsty causing its floor to flood. View attachment 1The field does not belong to me so it is unlikely that I could re-contour it. Suppose I could chat the farmer up to allow a JCB to do some digging, what sort of price would one expect to pay for about 30 Cu m of earth to be lifted and replaced, followed by rolling and re-seeding?
The more practical alternative is to put a vertical DPC on the pigsty to "dam" the puddle and a french drain and field drain to allow the trapped water to escape (other then via the pigsty!). The problem is of course compounded by the lack of foundations, so digging a trench adjacent to the wall would require some form of hard material to keep the walls in place, then the DPC, then a trench containing the field drain and pebbles.Any suggestions?
Frank

 

[Penners]

I think your drawn solution looks as good as any, but I wouldn't put the French drain so close to the pigsty back wall. Move it uphill maybe a metre or so and you haven't then got the problem of risking damage to the pigsty wall.

 

[Flyfisher]

My instinct would also to keep away from the wall itself, assuming the field owner is amenable.

I'm not sure about costs for a full-sized JCB but I used a local 'man-with-a-mini-digger' for some trenching work a couple of years ago for £200/day. It's surprising how much soil they can move once they get going, especially as they only have to temporarily move it to one side rather than load it onto a trailer.

 

[MdB]

You want a mini digger for that sort of job - I think ours was around £80 per day with £20 delivery. Something like that anyway. It took me about 2 days to get up to full speed but if you have some sort of coordination, you can get a lot done on your first day. (They are also great fun)

I would also vote for digging the trench a good distance away from the wall so as not to cause issues and to make life easier. I would also suggest having the permeable membrane on both sides. The DPC will just trap moisture from getting to the drain rather than stopping it getting to the pig sty.

(oh and of course, by 100% confident on where pipes / wires are before doing any digging.)

 

[Lime]

Put a drain in the floor of the pigsty?