Storm proofing a dry stone wall?

[chuckey]

It would seem that we are getting excessive rainfall now a days. The old fella down the lane has had his property flooded twice in the last two years - for the first time in 62 years!! The back of my cottage is below ground level but has land drains and seems to be completely dry under "normal" rainfall. However when the deluges happen (>40mm/Hr), the water rushing down the hillside, gets through the base of a dry stone wall, across by garth and floods into the back of the house. So I want to install a 6" high flood barrier on the outside of the wall to divert the water down the hill. My problem is to do it neatly, as the surface of the wall is far from flat or regular. A really upmarket way would be to dress a 18" wide lead sheet along the bottom edge of the wall, with 12" buried and the top 6" tightly dressed to the stone. A really down marker way would be to use "Viskerene" (Sp.?) instead, light blue in colour with its top edge flapping in the breeze. Even rendering would be ugly and difficult, the buried stones would be muddy and it would be difficult to finish the exposed surface nicely, without making the thickness over 3", so it would look awful. I have got a lot of roofing limestone "slates" (about 1/2" thick), which would look nice but for the unevenness of the surface to which they would be fixed. Any ideas?
Frank
Foot Note:-
When we visited after the second flood, I opened the barn door, 30 yards up the lane from the house, facing onto the lane, I noticed a pile of detritus just inside the door. On closer examination, the water had turned the lane into a beck, whose peak level was something like 9" higher then the edge of the road, the water flowed in under the door, "floated " all the wood shavings, which then backed up against the inside of the door as the water receded. :roll:

 

[Penners]

I think the problem you will have is cladding the wall with something that will deflect the surface water but won't tend to imprison damp within the wall. Even a sheathing of lead, although not actually "stuck to" the masonry, would greatly reduce the flow of air across the wall.

Would it be possible to construct a low wall a little way away from the house, that would act as a barrier to this flowing water? Maybe you could incorporate a gateway into it, with provision for a water-resistant flood barrier to be inserted into the gateway in times of risk.

It seems to me that this could achieve your aim without stifling the wall, and could perhaps be more aesthetically acceptable, too.

 

[worms]

Penners, my reading of this was that there already is a low wall up the garden and it is this dry-stane dyke that currently allows all the water to pour through rather than deflect it.

I wonder if the answer is to dig a shallow ditch in front of the wall?

 

[chuckey]

Worms, unfortunately the land on the other side of the wall is not mine. I have this cottage then a garth (garden to you Southern Types!), then a barn and pig sty all along the field boundary. I have re-pointed the cottage and installed a vertical damp course and drainage pipe and gravel. So the cottage is OK. The same is going to happen to the barn and pigsty. But the garth dry stone wall, it seems excessive to point the whole wall, because it is basically a linear pile of stones, so it would take an excessive amount of mortar and it would the only pointed drystone wall in Wensleydale! I do not mind the background under ground water filtering under the wall, as the next target (downhill) is the protected cottage. Its the 3"+ of surface water that is overwhelming the drainage provisions at the back of the cottage (actually at right angles to the boundary and wall). I am leaning towards marking a line at the base of the wall (6" up from the field) and just pointing underground and up to this line, but I'll have to finish it all of by hand and the lime mortar "skirting board" will show up like a sore thumb.
Frank

 

[agbagb]

Would clay and vegitation be enough to divert the worst of the flow?

 

[worms]

Worms, unfortunately the land on the other side of the wall is not mine. I have this cottage then a garth (garden to you Southern Types!)

Hey! Who you calling Southern? Wensleydale is just north of London, when viewed from here!

 

[Penners]

Chuckey - you need to understand that Worms has a good view of the North Pole from on top of his spare room wardrobe.

We'd best not enquire what he was doing on top of the wardrobe...

 

[Schoolmarm]

Late reply here but the wall would be compromised by making an area flat and water proof along the base, and the forces of the water are likely to shove it over.

 

[Zebra]

Some sort of new land drain arrangement within your, what was it, garth? Wouldn't that leave the wall alone but divert the water before it gets to the house?

 

[LadyArowana]

Some sort of new land drain arrangement within your, what was it, garth? Wouldn't that leave the wall alone but divert the water before it gets to the house?

Yes, basically a storm drain.