The Brew Cabin

I need to lay a lawn, small wall 6mtr and with flagged path with kerbed edges the 16mtr length but the land is full of water. The owner has said it always floods when rains.
SO he covered his 16 mtr x 7 mtr garden with 25 ton of top soil, with no compaction. So you can imagine the state.
He dug a small found about 300mm but that is full
Of water too.
I think the best way to sort out the water is to dig a large trench the width of the garden at the bottom and about 1 mtr deep, fill with large stone, then long trench's with perforated pipe and gravel leading to trench to disperse water.
Q1. Will this drain the top soil as I don’t want to take it out.
Q2. The ground is soft my wall is about 800mm high with four pillars with single brick between, how deep should my founds be?
There are no manholes to run pipes to.

Q1 - it would work if there was somewhere to outfall, but you say there is no drainage point that can be used, so to where would this planned interceptor drain go? Simply digging a trench and installing a land drain or a soakaway will not work unless there is somewhere for the water to go.

Q2 - You need to go down deep enough to find a firm base, preferably clay. You shouldn't pour a foundation over topsoil or suspect/iffy ground. Find firm, stable ground, then pour a 150x450/600 footing.

right I found out that were the trench is at btm of garden there is an underground spring or well of some sort so the water will seep into there.
About 1mtr down I hit clay, Will I have to dig down to clay level for perforated pipes and if so what level will the pea gravel be from the top soil level and dose the pipe needs to sit on the clay?
I'm also putting a 6ft fence with posts @ 8ft (2ft in ground using post mix down to clay with broken concrete to bring post up to height.) the ground is so soft I don’t think it will hold posts, as the old 4x3 posts pushed over with medium force. HELP it's like working on a swamp.
I was thinking of fastening a couple of feet to btm of post's then hardcore around, then post mix? What u think as i need to keep cost down.
THANX.

Water will not seep into a spring! The reason the ground is so wet is probably because the spring is flooding the ground, and you could spend literally thousands attempting to ameliorate the problem, involving the installation of a proper drainage system to carry the spring water elsewhere. I can't help thinking that you're peeing into the wind tryuing to overcome this problem on a tight budget, and you might be better off developing a strategy that makes the most of the spring, rather than try to turn a swamp into firm ground.

The standard spec for a collector drain is shown on the [url=htp://www.pavingexpert.com/drain03.htm]land drain[/url] page, but I repeat: unless you have somewhere to send the water, you're wasting your time.

For the fencing, you might need to consider using longer posts, say 2.7m posts, with 900mm buried, rather than 2.4m with 600mm buried. If there's still an issue, then lateral braces (aka "sprags", "rakes" or "outriggers" ) may be necessary. Your notion of fastening "feet" to the base of the posts, and then backfilling with inert hardcore will not work if the ground is loose. A longer posts and a good, solid backfilling of concrete, sufficient to counter the force of the wind on the panels, is the simplest option.

Thanks. I'm also working at the neighbors’ garden, I was informed that his father dug trenches, filled with hardcore then backfilled with soil and his is a lot drier.
Back to the garden in question, at the bottom there is a patch of grass about 3mtr's wide and the ground is a lot firmer, I read on this site that grass grows greener were the drainage-line runs and seen this in the past, (with out much thought,) anyway this is why I think the spring runs under this patch of grass, the rest is baron wet soil.
I’ve seen the spring at the neighbours’ garden and I think it would take the water away. (Fingers crossed)
I think your right on the posts so I’ll give it a try.
I'll let you know how I get on, Thanks.
I don’t use the net much but must say that your site has been the most helpful and informative that I� personally have had the pleasure to have viewed
Also thanks for the very quick response to my problems.

You’re right that the water needs channeled away.
So what I’d like to do is: there are three gardens backing on to our garden which have manholes in them. 1 is council, then ether side is private I have asked 2 of the tenants but they said I will have to get the relevant council permission?????? Could you fill me in with the law on this one?
Also I’ve installed my perforated pipes to a large sump trench , I wish to take an overflow pipe from this trench to one of the M.H would this method be all right as the lady in the private house was worried about silt from my pipes . also if this method is ok is perforated pipe all right to run to the M.H.
would it have to be a company or can any competent person do the work.
Thanx Dave


(Edited by dak uk at 12:33 pm on June 7, 2003)


(Edited by dak uk at 12:52 am on June 8, 2003)

The law regarding connection to drains and sewers is somewhat complicated, but, if there are two access chambers on private property, then you may be able to connect to them, as long as you have permission from the property owner, and this may need to be some form of legl agreement to cover eventualities such as dealing with blockages, cleaning and maintenance, access rights, etc.

The first thing to establish is whether the manholes/access chambers are part of a private drain (which is the property/responsibility of the properrty owner) or a public sewer, which is most often 'managed' by the local authority. Just because a MH/AC is on private property it doesn't necessarily mean it is a private drain. The deeds and/or your LA should be able to clarify that point, and then you know who to approach to seek permission.

To overcome any problems with silt, you could construct a Catch Pit, which will trap all silt before it can enter the main drainage system. Silt is not usually amajor problem with drains and sewers as the inbuilt falls are normally fast enough to ensure any silts and clays that do find their way into the system can be washed along by the flow of water.

Finally, when it comes to carrying out the work, it all depends on the layout. I would strongly recommend a drainage contractor, who has all the right tools, the right experience and the right training for working in sewers, but, if this is a private drain, on private property you could undertake the work yourself. Even so, I'd still get a drainage contractor to give you a no-obligation quote for the work, just to see whether you think it's worth all the hassle.

This sounds like good news.
I think the manholes are under the council authority so would i need permission to use there M.H.
The best located M.H. would be the council property as the gentleman said if i got council permission he wouldn’t mind (as he said he "would have no choice as to let me use the M.H.").
So do you think the person who has the problem water should get the permission then i can get on with the major work.
thanx

Yes - have a chat with your local council Technical Services Department and see if you can cajole them out of their office, while the weather is good, to come and have a look at your problem and advise you on the best or most practicable solution.