Mystery manholes

[warwickwater]

We have just purchased an ex agricultural property (barn) that was converted in the 80s to a house. It has mains water, mains electricity, a sealed septic tank (maybe i mean cess pool - no soak away, just pumped out), no mains gas, and oil heating.

In the parking area outside the property I have two mystery manholes (for want of a better description). They are some distance from the cess/ septic, and nowhere near the known locations of the foul pipes or the oil line.

The first mystery....

Untitled

• warwickwater
• 2 Sep 2008
• 1

Under a relatively new lightweight manhole (ie not iron and ancient). There was a plastic cap sealing the 'assembly' shown - the outer metal pipe and blue pipe are fixed, the inner white pipe (with the cross T to hold it) can be pulled up - like a dipstick. I have pulled the 'dipstick' up a good 30m and it is still going!! - it seems to be weighted on the end (id guess 5-10kg worth)

Surely to bore a metal pipe this deep must have cost someone a fortune - and then not connected to anything. Or conversely if its redundant (a well?) - why not just cap it with a paving slab rather than a neat access?

Second mystery.....

Untitled

• warwickwater
• 2 Sep 2008
• 1

This one is 5m from the first, and under 6 inches of water. The valve assembly looks quite intricate - I didnt try and move/ open it. The white sediment is chalk like but hard in places, didnt try to dig into it. No noticable smells from either manhole.

Any ideas anyone? Plumbing and heating was the closest i could find as a category.

Thanks in advance for any information / guesses.

 

[JohnD]

I have pulled the 'dipstick' up a good 30m

surely not

 

[warwickwater]

Yes, thirty metres (assuming that was a straight question and I'm not missing some humour somewhere?)

 

[JohnD]

must be a well then

or else a heat pump. But 30m seems very deep for that.

If it is a well i think you have to get an abstraction licence for it. Your local water authority might be able to help. Useful if you have a farm, or perhaps a swiming pool.

 

[Watchmaker]

This all seems a great mystery but, as this was originally an agricultural property, is there the possibility that mains water is a recent addition and could the bore holes be a previous attempt at tapping into an underground water supply? The intricate device, on the second manhole, is equally puzzling. Is the property on re-claimed land and was this a vent for methane release? A word with the neighbours might shed some light on it.

 

[warwickwater]

The land is and always has been agricultural - the building is 100+ years old and so a methane release/ dump within 10 metres seems unlikely.

I did assume something that deep must be a well - just intrigued as to why it was preserved, lined and properly capped!

The neighbours know nothing, but they themselves are recent movers.

Any more info appreciated of course!

 

[mattylad]

I take it previous owners are not available?

 

[warwickwater]

'not available' would be a concise way of putting it, yes.

 

[Onetap]

No. 1 looks very like a borehole/well, like this;

http://www.wbadmorgan.co.uk/info_drilling.htm

Steel well casing in a borehole with the space between packed with grout/concrete.
The blue water pipe is from a submersible pump.
The white pipe- I haven't the foggiest idea.

Drop a weight down on a line, see how deep it goes and whether there's water at the bottom. Try e-mailing a well boring contractor, see if they can confirm this. You should be able to lift the pump out on the blue pipe.

Don't such boreholes have to be registered with the Environment Agency or some such? Would they have records?

 

[warwickwater]

One solved - 35 metres of pipe later theres a branded valve on the end of the white pipe - seemingly its for water sampling. Theres some 'inrastructure' nearby that maybe needed it as part of its planning maybe.

The other manhole with the mystery valve assembly - still a mystery!

 

[D_Hailsham]

Have you asked you local water company?

 

[Watchmaker]

"Have you asked you local water company?"
Avoid doing that at all costs. That will be Severn Trent and, no doubt, they would jump at the opportunity to whip a large bill into you for something or other or, a rental charge for having access to one of their aquifers.

 

[Bendo]

This may help

http://194.66.252.141/website/gdi/viewer.htm?Title=GeoIndex

Use the toolbar to zoom in. Once you've zoomed in enough you'll be able to select 'Borehole records' from the drop-down menu on the right hand side. Click 'redraw map' and the borehole locations should appear.

You can select borehole information using the 'i' button or Area select on the Query section of the toolbar

 

[Onetap]

One solved - 35 metres of pipe later theres a branded valve on the end of the white pipe - seemingly its for water sampling.

I'm not certain it's a well borehole, it just seems most likely.
The submersible pump is possibly trapped by sediment in the bottom of the borehole and there should be a power cable to it. Maybe someone tried pulling it out with the cable.

The other one is possibly also a capped borehole. They should be sealed to prevent groundwater contaminating the aquifer. I can't say why they'd want two. Maybe a ground source heat pump system, one pumping water to the heat pump, the other returning it to the aquifer.

 

[JohnD]

That's an interesting map. On "water wells" it shows a green triangle at the end of my road, where there used to be an old agricultural tractor shed (since burned down and houses put up)

I can't see how to get any more detail about it though.