Lawn Advice please

El Camino

Hi there,

I'm looking for some advice as to how to add some basic drainage to my garden. I'm not long in my new house and all of the recent rain has shown up a few problems. The mail one being that the top soil is very wet and retains a lot of water. It has been suggested that maybe i need to add a drainage pit. However, I'm not exactly sure how to go about this.

It's a semi-detatched shouse so the garden is not the biggest. The lower two-thirds of the garden are particularly bad. I've recently killed off all the grass (mostly weeds) with a good spraying of round-up. My intention was to rotivate the entire garden, introducing new topsoil to level it out and sew new grass.

Before i do this i presume i should consider this drainage so that the garden is not swamped again soon.

Has anyone done work like this or could point me in the direction of some advice?

Thanks...

bmaxi

Do a search of this forum, there have been several threads on this and you'll get some good advice in them.

*Derek*

The other altervative for you is to use Artificial grass. Its becoming popular nowadays. We've just put some down at home and i think it looks fantastic.

maggie797

dig in lots and lots of sharp sand...dont underestimate what you will need.... we dug in loads last summer as we were mainly clay and the difference was unbelievable, it really helped with drainage. it was weird when we first set the grass as it felt like the ground was really loose, but the sand does sink into the soil really well

El Camino

As bmaxi suggested i have done a search on this forum, which i probably should have done first and there are some great threads to explain what to do here.

It looks like i'm going to go down the route of the french drain with a large soak hole off this.

Thanks,

A lot of work ahead!!

rhonin

It is a lot of work but well worth it. I had the same problem with our new house. The builder's machines had compacted the soil so much the water just stayed on the surface. I followed Delly's guide http://www.boards.ie/vbulletin/showthread.php?t=2054939061
I had to plumb my drainage into the rain water system as the garden was sloping towards the back of my house and the water in the soakways did not drain quick enough.

El Camino

Hi Rhonin,

It seems that i am in exactly the same position. The water is just sittin on top of what should be a lawn. THe garden is slightly sloping towards the back fence and this is why i was hoping to add the soak hole at the end of the garden.

What's involved in plumbing this directly into the rain water system. It definitely sounds a bit more tricky than the soak hole option. Also, it seems from what you're saying that the level of the inlination of the trenches is critical so as to get the water to either the soak hole or rain water system as quickly as possible.

Delly's guide is great but it's good to hear from others who have done a similar piece as I'm sure there have been many different experiences out there (not all good I'm sure) & i would like to be prepared for all eventualities.

Any other opinions on this??

rhonin

What I did was dig a soak hole about a meter deep. Dig the trenches to lead into soak hole, similar to Delly. You don't need a big fall in the trenches. Just enough for the water to flow.Then I dug a trench from the soak hole to rainwater manhole. I used a solid sewer pipe for this last bit. So when the soak hole fills the water flows into the rainwater system.
I was kind of lucky in that there was a manhole near the corner of my footpath. They was a spare tunnel in the manhole so all I had to do was break a bit of concrete to allow me to put my pipe into the spare tunnel. I've attached a picture to explain it better.


I can't see any problem with the way you are planning to do it. When you dig your soak hole you can test it by putting some water into it and see how long it takes to drain away. If it doesn't drain you have to dig deeper! You will need to dig past the clay for it to work. If your soil is like my mine it goes like concrete when dry. I used one of those large iron crowbars to lossen the soil. About €15 to buy. A pick axe would do too.

Sonnenblumen

rhonin wrote: »

It is a lot of work but well worth it. I had the same problem with our new house. The builder's machines had compacted the soil so much the water just stayed on the surface. I followed Delly's guide http://www.boards.ie/vbulletin/showthread.php?t=2054939061
I had to plumb my drainage into the rain water system as the garden was sloping towards the back of my house and the water in the soakways did not drain quick enough.

Soil can and often does recover from compaction caused by heavy machinery etc, although it can take up to 3 years to recover. Alternatively rotovating area and mixing some grit etc can alleviate problem with water lodging on surface.

In more serious cases installing a soak pit/landdrain within metres of of problem might help, but a nearby soakpit is a a stop gap solution.

Installing a land drain is probably better option for severe cases but only when it is possible to take water away, and 2-4 m is again not going to work.

A better option is to collect surface water and divert to nearest storm drain. Not a good idea to send to foul sewer. Install pipework to collect water must be at least 400-500 mm below surface to be effective.

Also do not underestimate the role and effectiveness of using planting to assist in tackling excess moisture.

El Camino

That's great Rhonin. Thanks for that. Just had a quick look and i've got a manhole cover in a very similar position as your photo so this could be an option also. I'll take a better look at the weekend and add a pick-axe or crowbar to the shopping list.

I was planning on putting the soak hole at the bottom of the garden but may re-think in light of your advice.

We have now had a few days without rain and i've taken a stroll around and it's still very wet down there so i think that some form of drainage is necessary. Also, this area is quite boggy (midlands - laois).

Ultimately, i was planning on putting in some work to the garden and doing a bit of landscaping and my big concern was that i would do te work only for the poor soil to und it all. So i really want to get this right first time around. I don't want to find myself in the situation next winter where i need to re-do some work. Maybe begin with soak pit but add a connection to rain water system to handle an excess.

bmaxi

All the land drainage pipes and soakaways in the world are not going to help if the water can't reach them, so it's best to improve the quality of your soil while you're at it. You are going to put a lot of hard work into creating the drainage, so go a bit further and add plenty of grit and organic matter to the soil and dig or rotovate it in thoroughly.

rhonin

bmaxi wrote: »

All the land drainage pipes and soakaways in the world are not going to help if the water can't reach them, so it's best to improve the quality of your soil while you're at it. You are going to put a lot of hard work into creating the drainage, so go a bit further and add plenty of grit and organic matter to the soil and dig or rotovate it in thoroughly.

Thats a good point. There is no point in putting in drains if you cover it with the same bad soil. What the builder left me with was basically subsoil. All the topsoil was stripped away. When I finished my drains I bought good topsoil and its working a treat.