Flooded Messy Garden, levelling advice please

[Jacka]

Last year I moved into a house and after sorting out the inside, I’m about to have a go on the back garden as it’s a mess.

The details
The garden is approx 10 meters long and 12 metres wide
It has two large decking areas from the previous owners and I plan to take the lower one out which I think it was put in to cover the water logged garden.
The garden is on a slope which I would imagine is about a metre drop from the house to the bottom of the fence.
The drain is about 4 metres into the garden central the house and sits under the first bit of decking.

Basically because the bottom of the garden gets really damp and marshy I want to level the bottom half and try to put some drainage back into the manhole (is that allowed??). I believe the water is coming from the fields through my neighbours garden, but because they have decked their whole garden it’s difficult to see if that’s definitely where it is coming from.

My current thought to do this, is to build a horse shoe wall to sit around the bottom of the garden (in the ground to clay level about 12 inches down) level it and lay perforated pipe into the drain. I would also hope the water is held back by the wall, if it’s coming from the neighbour’s house.

Does anyone think that is the best route to go down or can anyone offer any other ideas.

Let me know

Thanks

Jacka

 

[rxbren]

your not allowed to put any new storm/rain water connection into any manhole especially if it is a foul manhole.
the correct way to do this is to install a large soakaway - minimum of 5m from any buildings wether it works or not all comes down to the build up of the ground round your way

 

[Jacka]

I've thought about a soak away but when I've dug down its clay from about 12inches so I think it would just sit there (typical for County Durham I'm told). The only other option would be to build a wall at the bottom of the garden remove the fences and re install) and raise it. Then fill the bottom metre or so with either gravel or storm crates and let it sit there.

Regarding the soil drain, my rear gutter goes into it. Would this reflect the age of the property (1960).

 

[rxbren]

foul and storm drains used to be combined but due to the sewage plants not being able to cope with the extra storm water when the weather gets bad they stopped the combined systems and either use soakaways or have a seperate storm water pipeline. So you will fnd at older properties that they have this system
you really need to dig down at least a meter to see what ground conditions are like although when digging down deep you need to take precautions and depending on ground conditions may even need to shore (support the edges) the hole
Ive got a couple to dig in a few weeks and they are going to be around 1.6m deep to reach suitable ground

 

[Jacka]

Cheers for the info. What I've one so far is just dug a trench 12inches deep across the bottom of the garden (1m from the fence) to see where the water comes from. Next nice day ill see if I can go a bit deeper but I think it will b heavy clay.

If the water is coming from the neighbours garden should they be responsible for stopping it?

 

[rxbren]

as your already digging id dig down an extra couple of foot
not sure about neighbour being responsible if its just grass in their back garden if they had paved it you might have some chance of them being responsible.
you can install a large soakaway and if it doesnt get rid of the water you can pipe to the manhole although that depends on levels and may need building control or permission from water board

 

[Jacka]

I'll have a look over the next couple of weeks, when I remove the other decking.

Say if I do build a soak away and feed it back into the drain, what would happen if the drain ever blocked? Can you get a drain valve to stop any foul coming back out?

 

[Jacka]

further pictures

 

[rxbren]

not really anything you can do thats the risk. they do, do a one way flapper for foul drains but from what ive heard serious money to buy and the one ive seen fitted occasionally sticked when was origionally fitted which was a right pain in the ass as it was over 2m deep to the invert

 

[Jacka]

Ok cheers for that

Looking at the steps where the drain is under. Do you think I could get a soakaway back to it?

From the last picture, where ive dug, that is probably the highest point which gets swamped. If I raised the bottom of the garden slightly( levelled it), say by a foot and filled it with a load of gravel/ rubble do you think the water would sit there so I wouldn't notice?

 

[Jacka]

Well it rained and this happened. Can believe how much water is there. Too much water surely for a soak-away