Draining the graden

Xennon

hi folks,
Heres the scenario, I have a garden that has now been walled in, there is a drop in one corner of about 2.5', which I entend to fill in to level the graded, the retaining wall has been build (with slots for drainage). Now my problem, the raised section retains alot of water (odd I know). So heres what I was thinking of doing, digging a trench or two into the raised area towards the lower area, lay gravel into the trench, lay drainage pipe, and more gravel and top off with top soil.
I was going to run mabye 3 of these trenches across the garden, to drain it, all leading to the same area (where the slots are in the retaining wall, allowing the water out the other side of the wall).

Should I??..Any recomendations.. Any thoughts??..All info welcome...

Dave

GreeBo

A worry that comes to my mind is that if all the garden is draining to the one point, you might want to do something to that point, rather than just let the water run off as this will eventually erode away whatever its landing on and might cause problems for your wall.

I'd dig down a foot or two and fill with gravel and let the "final" pipe drain into that..
Just my opinion though!

Also, if your garden is retaining a lot of water you probably need to look at the soil content. If its very clay like then this will retain water, you could hire a hollow core machine (or buy a manual one) and fill the cores with sharp sand.
Do this twice a year will improve your soil makeup.

shabbyroad

a hollow core machine

now that got my attention.

We've got the same problem and it's not getting any better. The problem is primarily the soil which is very clay like and doesn't drain well. We put in a couple of gravel-filled trenches which have helped a litle.

What's a hollow core machine ? is it something that basically digs a deep narrow hole into the ground ? (like one of those cheese-sampling devices... am I losing ye here ?). So it allows me to create small silos of sand in around the garden to help with drainage.

GreeBo

yep, its like a bunch of them on a roller that takes up a load of cores in your garden which you then fill with sand/ fine compost mix.
Sand for drainage, compost for healthy soil, will stop it retaining so much water.
You will have a fair amound of waste soil to deal with though, be warned.

shabbyroad

does it make one hole at a time or several ? how deep does it go ?
(I'm trying to picture this)

GreeBo

it makes a bunch.
Think of a roller for the garden that has hollow spikes sticking out of it at intervals...as you roll it over the lawn it takes up a load of cores (maybe 0.5- 0.75 inch Diameter, anything from 2-5 inches deep depending on machine) and spits them onto the lawn.

I have seen them in B&Q, Homebase, Argos even I think...
Its what they use on Golf Courses for greens and fairways (though obviously the domestic version!)

shabbyroad

Ah Right. Now I see it.

I was thinking more along the lines of something that would go 2-3 feet into the ground with a diameter of 1-2 inches which I'd fire sand into. But that probably wouldn't work.

I'll investigate what you've described. It might do the job.

GreeBo

Though if you are having real problems you will need to create drains to remove the surface water
As has been described, 1-3 foot deep channels filled with crushed rock/gravel, can then be covered with permeable layer and filled with topsoil.

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   * <--- this drain bit is important, you want the water to have somewhere to go so make it deep

Xennon

thanks guys,
I think I may be ok...
What I can do is ,
I will run the drainage pipes thru the wall and out the other side, I''l build up the far side with gravel, this leads to a farmers field next door and is drained along near there so it would act as a drain away.
Would this be the way to go?

Dave

GreeBo

yeah, I guess the further from your wall/foundations the better