Garden drainage

Effects

I'm looking for some advice on garden drainage.
The area is in a new build house. There's rubble on top of the subsoil, placed while building was being carried out. The topsoil was brought in afterwards. It's a fairly heavy clay soil and is about 25cm deep in most places. Garden is sloped.

When it rains the water pools at the bottom of the garden area. It's lower than the drain so doesn't run off into the drain. Drain is there for the concrete section.

I've shown where the pipe runs that connects the drain to the manhole. At the manhole connection the pipe is 80cm deep.

I'm getting turf put in next week so would like to try and rectify ahead of this.
I'm thinking of digging to the pipe below, drilling small holes in the pipe, covering with lawn fabric, top with gravel/stone to close to the surface.

Will this be enough? Any advice is appreciated!

Im no expert but from the bits of drainage ive put into my own garden i think it should work to some extent.... however If it was me I'd put in a drain from the top (as you look at picture) to the manhole and also one running parallel to the path before diverting to the manhole.
I'd also use some perforated pipe.

It looks like there is a problem with drainage anyway. The wall on the left looks like it has been damp and covered in moss for quite some time.

macraignil

TheTorment wrote: »

It looks like there is a problem with drainage anyway. The wall on the left looks like it has been damp and covered in moss for quite some time.

I can't see any moss on the wall on the left of the picture. It looks to me to be more like algae on the top area of the side of the wall and I don't think this would have anything to do with the wall taking up moisture from the soil. We get enough moisture in the air for some algae and lichens to grow naturally when hard surfaces are out of drying winds and direct sunlight. They are not harmful.

As to the drainage question I think what Effects describes doing sounds like it might work as long as you're sure that the pipe is just garden drainage and not draining foul water from the house. I'd be inclined to put a couple of small shovels/handfuls of grit where the puddle is next to the drain but its hard to judge from the photo how deep the puddle is and obviously you would not want solid material washing into and clogging the drain.

Effects

Thanks for the replies. The left is the original boundary wall, until recently it was covered in ivy and vegetation. That's part of the reason it's green I'd say.

I've dug down to the pipe between the acodrain and the manhole. I'll drill this and I've got weed fabric to cover pipe and contain the stones.
I thought I might dig another shallower trench from left to right at the front, which can lead into the other drain that I've dug.

This pipe is purely taking surface water from the roof and patio area so not worried about it being foul drainage.

It was hard work digging down 800mm to reach the pipe so not really looking to do any more digging at the moment!!