High natural water and a pond- advise please

I have an interesting problem.

Removing an old fence post that was about 1m deep in the clay soil left us with a hole that has started to fill with water.

There are two options- a damaged drainage pipe or natural water table. I'm starting to exclude the pipe option as we probed deeper but found nothing, and the water level doesn't react when we use a lot of water (washing machine etc), and doesn't go down over the night.

I have contacted the water company for their opinion and advise, but very likely they'll just say it's my land and my problem.

So- what's the best way to have a flexi- liner pond over the area?

I could just make it shallower than planned, about 60cm deep leaving a good 40cm safety zone, or try to do something with the natural water level (unlikely to work). Or something different.

What do you think?

The hole with a spade:


Current water level:



Thanks for advise!

 

Hi

I would plant moisture loving plants .

is it just the one spot or is the area around there soggy ?

You could 3/4 fill with rubble then put soil on the top at least it would be more stable

are you on a water meter ? Soon know if it’s a leak when the bill goes up

 

I'd have to dig a hole somewhere else to convince myself that's not a broken water pipe.

I assume the water doesn't get deeper overnight?

 

If you are on a meter then turn everything off and look at the meter readout over a half hour, see if it moves.

 

We are not on meter (and under the circumstances, I'm not going to ask for one ), and the incoming water pressure is stable and good.

The water level in the hole remains fairly stable.

We have dug two spades deep elsewhere, and at that depth the soil is fairly moist everywhere. In the hole, we reached different colour clay in the bottom, I suppose it could be sub soil- yellowish/ orangey hard clay.

We are on a gentle slope and some distance away there is a natural pond about at our level. There are ponds and streams all over the place but the mining has made the geology totally unpredictable.

I'll try to bribe The Child to dig another very deep hole somewhere else to see. In this draught the clay is rock hard so it will cost me a few ice creams

 

Be cautious if there is a reasonable chance that its mine water-it may well be contaminated. Having had cause to determine a potential main leak, when the water company sent an 'engineer', he proceeded to dig a hole, then troubled to don waders and stood in the water for half an hour!
He then explained that he was determining whether his feet got cold; indicating a watermain, or warmer, indicating a sewer leak,which was his conclusion.
Following 3 days of further excavation, it was found to be a surface water drain blocked in previous roadworks.
In the current drought, if convinced it was unsullied, I should invest in a small pump for irrigational purposes

 

You're lucky, the bloke they sent out to my place had divining rods and took the whole day to find the leak under the path after digging up a fair few places.
He then reinstated the path with two bags of ready mix and a broom.

 

A pond with a maximum depth of between 2 and 2 1/2 feet (60cm to 75cm) should be deep enough so I would just go down to that level.

 

A little update:

The water company called me and checked their data for all pipes coming to and going from my house. All incoming pipes are on the road side. They were very good, correctly pinpointing the sewage pipe going from the extension turning left to the neighbouring house, exactly what I had deduced already.

They confirmed there are no pipes whatsoever in our back garden. None of the houses in this horse shoe formation has, it's just the gardens that gently slope towards the road and then down to the burn.

They also had a look at the local area geography and we discussed the various natural and mining leftover ponds and streams around us and concluded that I have indeed hit the natural water bed.

The disappointing news is that I can't have the very deep pond I had hoped for, but around 60cm should be enough and if I'm not happy, some raised edges can be considered in the future.

The good news is that I'm not going to have any lawn, just main gravel path and lush cottage style planting everywhere else- and high water bed is probably going to be a blessing for that plan.

We'll push the infamous stake back in, mark the safety level zone on it, dig the pond and wait to see if 30cm clearance is enough.

@infradig , you must have a self control of a saint not to have asked if the engineer had ever considered a thermometer

 

You do not say how deep you would "like" your pond to be. 2ft., is very shallow allowing for evaporation and freezing. You would need to grow pygmy waterlilies if they are on your plant list.
I think I would just go for it, despite the water level, it will be hard work and messy, but dig out the depth you want, allowing a few inches for padding and liner, use newspaper folded, old carpet or purpose made fleece padding before putting in a heavy duty liner. The natural water will flow around the padding etc. and not interfere with the pond. A raised edge would help prevent the natural water from running into the pond if you normally have surface puddles from it. If you have found yellow clay it sounds like clay subsoil so I would avoid putting it on the garden. When I dug my pond I went down to 4ft., so fish could hibernate safely.

When I was working near the bottom of my garden recently I came across some damp soil, not very far down. The rest of the area is like a dust bowl. I know the septic tank is not far away but there was no smell so I have no idea why that patch is still damp. Just thought it might be a good location to plant a replacement rhubarb. My garden is surrounded by fields so no pipework around that I know of. I am pretty sure there are underground water courses around here.
I have had a go at water divining for fun, it is extraordinary, must get my rods out and have a wander around the garden again. I have an odd structure which I thought might be the remains of an old well, now backfilled with rubble and concrete, didn't pick up water near it though. A lot of properties down here have bore holes for water so there is a chance I may have an underground spring nearby and there is a working clay pit further up the hill. Never ending possibilities