I'm trying to sort out drainage for a large shed roof. It's 23 sqm. I'm going to stick gutters on it, but my nearest drain is the other end of my garden, 25m away.
My current plan is to drain the roof into a single, large (200 litre or similar) water butt behind the shed, then run 20mm MDPE pipe from there down the side of the garden and into the drain. Will this work? If my water butt is roughly a metre high and I put the drainage hole near the bottom, then I've only got a metre of head. I can raise the butt up, maybe half a metre.
I don't need any great pressure from the flow, just enough to reach the drain and to empty sufficiently between storms. I live in Leicester and the average rainfall is about 600mm per year.
I don't want to spend a fortune doing this.
I've looked around the net and on other forums, but no-one seems to have quite done the same thing. I asked a company about a similar setup but using a soaker hose instead of running to the drain, but they don't think there'd be enough pressure to force the water from the hose. I'd like to avoid using a water butt pump if possible - I don't want the maintenance, or the hassle for what is essentially waste water.