Garden not draining properly - very boggy - how to fix?

[uptown47]

Hi all,

My garden was recently re-landscaped. The earth is full of clay. Since the garden was done it became extremely soft underfoot and very boggy. It would squelch as you walked on it.

I've read that if you remove the turf from the top and fill holes with sand it helps with the drainage.

Am I right in thinking this?

Also, if I removed the turf from the top, is there a tool or something I can buy/rent that will drill deep holes in order to fill with sand? (and is it best with sand or gravel?)

Or is there a better way to improve the drainage of the garden??

Do I even need to remove the turf from the top? Could I just rent some powerful drill with a really long bit on it and drill through the grass and fill with sand?

Excuse all the questions but I'm lost with how to fix this.

Thanks for your help

 

[r896neo]

When you say re-landscaped what do you mean? Ground which has been re graded/ deep fills will be soft for at least a year depending on how well it was filled and with what.

 

[uptown47]

I mean, the ground was on a slope. The guys came and made the garden flat. They did this with a mini-digger. Digging out the top of the slope and re-positioning at the bottom of the slope. I think the to-fro-ing of the digger also contributed to compacting the clay'ey soil underneath.

 

[LesAshmore]

I did much the same as you ie my garden was on a slope and I had it landscaped (Levelled out) and turfed with borders etc, I soon discovered that the lawns were extremely soggy and in fact had a major problem with moss very shortly after, I then had trenches dug in my garden (7) and proper garden drains laid, I still had the same problem, as I love lawns I had my lawns dug up and proper base laid ie Gravel and sand and lawns re laid, I still had the same problem and after just a small amount of rain my garden was unuseable, I had a BBQ at the top of my garden and couldn't use it hardly, My lawns were disgusting and covered with bare patches where drains were and Moss where they weren't I gave up after 9 years trying and last year I had astro turf laid, I have now got my garden back and even when it is raining I can walk out and up my garden even on the "Grass" I have used my garden more last winter than I have ever done before, Best thing I have ever done.
By the way I spent £5k on Drainage mods etc that was a total waste of time and money.

 

[r896neo]

Well it sounds like your garden now has a layer of poor sub soil dredged up by the re grading and a lawn laid on it. Made up ground ill be soft for a year or so. Try and stay off it when its very wet.

Les experience is the major problem with garden drainage, you can spend big money on it and still not solve it. If your on heavy clay there is no real fix.

Hollow core aeration is worth trying first but your drill theroy will have no effect.

 

[uptown47]

Thanks for all the advice and sharing your experiences. I really wanted to avoid ripping it up and putting in astro turf but it might come to that.

 

[endecotp]

is there a tool or something I can buy/rent that will drill deep holes in order to fill with sand?

Search for "petrol plug aerator"; there are videos on youtube showing what they do.
It sounds as if you might need to dig deeper, though.

 

[uptown47]

Thanks for the tip. I've just had a look at those but, you're right, I would need to go a lot deeper than this unfortunately.

 

[uptown47]

I had astro turf laid, I have now got my garden back and even when it is raining I can walk out and up my garden even on the "Grass" I have used my garden more last winter than I have ever done before, Best thing I have ever done.

Les, excuse my ignorance but why is the astro turf dry? Is it just that it doesn't retain the water? Or was it just that when putting in the astro turf you did something else to fix the drainage?

Thanks

 

[amfisted]

Clay gardens can be a drainage nightmare.

We moved into our house in July 2014, and the first winter we were here the rainfall left pools of standing water all over the garden. Eventually they drained away, but very slowly indeed. Last winter the deluges of December and January led to the ground becoming saturated until it simply couldn't absorb any more water, and one night we had a cataract pouring over the edge of the raised patio and flooding the lawn below. On the same night I had to drill a weep hole to release a huge amount of water which had run from a channel at the base of a retaining wall alongside the sloped part of the garden and collected in a void alongside the garden wall, threatening to undermine the wall itself.

I've tried making small soakaways by digging holes and filling them with gravel, only to find them filling to the brim with water, and I sank a rainwater crate only to watch it turn into an underground swimming pool. The ideal solution for us would be a soakaway in the lowest part of the garden which is deep enough to penetrate below the clay sub soil, but such a venture would require the use of a mini digger and access makes that impossible. I've considered laying land drains but there isn't really anywhere to take the water to without transferring the problem to my neighbours' gardens.

My long term solution is to spend the next few years digging out the upper layer of clay from all borders and replacing it with compost, topsoil and soil conditioner from my local recycling centre, and to put up with a squelchy lawn elsewhere; aerating regularly to alleviate the waterlogging as much as possible. Success depends largely on the amount of rainfall, of course.

 

[r896neo]

I have never in all my years doing groundwork and landscaping seen a clay pan which can be dug through to a free draining sub soil. It does exist of course but it is much rarer than people seem to think. If you have clay soil, you have clay sub-soil and it will never drain well or soakaway.

In my experience short of digging many metres into the ground you will not be able to fix it. The idea of removing the clay is a waste of time unless you have a large digger and free waste disposal.

Your best bet is draining it to somewhere via a blanket drain of 20mm clean gravel.

 

[bernardgreen]

Desperate measures that might pay for itself. Create a sump for the water to drain into and install a pump to pump water for use where it need not be clean drinking water. Flushing toilets, washing cars etc etc. It might even be clean enough for washing clothes etc.

It might pay for itself by reducing the amount of water through your water meter and hence lower water bills.

 

[amfisted]

I have never in all my years doing groundwork and landscaping seen a clay pan which can be dug through to a free draining sub soil. It does exist of course but it is much rarer than people seem to think. If you have clay soil, you have clay sub-soil and it will never drain well or soakaway.

In my experience short of digging many metres into the ground you will not be able to fix it. The idea of removing the clay is a waste of time unless you have a large digger and free waste disposal.

Your best bet is draining it to somewhere via a blanket drain of 20mm clean gravel.

Could you explain what a blanket drain is, please?

 

[uptown47]

I have never in all my years doing groundwork and landscaping seen a clay pan which can be dug through to a free draining sub soil. It does exist of course but it is much rarer than people seem to think. If you have clay soil, you have clay sub-soil and it will never drain well or soakaway.

In my experience short of digging many metres into the ground you will not be able to fix it. The idea of removing the clay is a waste of time unless you have a large digger and free waste disposal.

Your best bet is draining it to somewhere via a blanket drain of 20mm clean gravel.

Could you explain what a blanket drain is, please?

Exactly what I was going to ask. A bit more detail on this would be great. Thank you

 

[amfisted]

However, answer came there none, so I suppose we'll have to look it up. I wonder if its just a trench filled with stones?