Weird Garden drain

[spot]

Hi All,

My house was built in 1894.
Until the mid 60's the water supply was from a well (which I still haven't found!) at which point it went on mains water and sewerage.
Anyway, last week I was in the garden attempting to clear away some of the jungle when my foot fell through the ground and I saw water beneath.
"Way-hay!" I thought, I've found the well...
Actually, no.
What my foot had gone through was a rotten old rusted man hole cover.
Underneath this it opens out in what appears to be a square (possibly metal) cavity approx 6' square and about 10' deep that is fed with 2 pipes (blocked up with roots). See pictures...

I contacted the previous owner (who was there from 1952) who said "oh yeah, it's some kind of land drainage", but other than that knowing that it existed had no further info.

Does anyone know what the hell the purpose is of this?

When the cover collapsed it was almost full of water. I got a pump and drained it, and with the torrential rain we've had it was full again about 5 days later.
What's the point?
I guess water from the surrounding ground soaks into the pipes, drains into the tank and then what? Is it supposed to just evaporate???

Very odd.

Any info, most welcome.

Stu.

 

[Flyfisher]

If the house had no mains sewerage before the 60s, I'd suggest it could be a now-disused cess pit or septic tank (I'm never entirely sure of the difference).

 

[spot]

No, it's not the cess pit, I know where that used to be and it's completely the opposite side of the garden to that.

 

[fjpdesigns]

I used to live in a 18th century farm house which had a similar sized tank just outside the back door, but it was lined with brick. We reckoned it was to hold rain water which was used in the house for anything except drinking and cooking, i.e. cleaning , washing clothes and the like. There were also at least three wells around the house and a hand pump in the kitchen [ the old dairy ]but we never worked out which water source this was connected to.

 

[DaveBrigg]

I think fjpdesigns has hit the nail on the head. We have a similar chamber a couple of feet outside what was once a washroom, with traces of the brick pillars which once held up a sink. Ours is fed by two downpipes from the gutters, but there is some sort of overflow pipe at the top on the opposite side, leading further into the garden. If yours was full but not overflowing, and filled again after emptying, then either you have a very high water table or one of your pipes is also an overflow. I've heard the theory that rainwater was softer than that from the well, and so better for washing clothes.

There have been earlier posts from people who have found similar tanks beneath the floor of a house, with some interesting discussions as to how to treat them. Nuclear bunker anyone?

 

[Lime]

Such structures are very common in this area too.
Built to sometimes save water for washing/drinking sometimes just to take it and store it until it soaked away they go hand in hand with septic tanks and cess pools.
If they are used for saving water they do not drain away directly they normally have an overflow pipe so a certain level of water is maintained.
The soak away types usually have an earth/open bottom and no overflow.

 

[Lime]

................. disused cess pit or septic tank (I'm never entirely sure of the difference).

A cess pit/pool requires regular emptying and has NO outlet (or shouldn't!) while a septic tank "treats" the sewage to an extent then allows the liquid to flow out into the soil or water course.
It should be remembered that most older cess pits/pools were not connected to mains water originally so the contents were much more condensed that what we have today (which is mostly liquid) hence the differing pit and pool.

 

[AMc]

Looks a lot like the fresh water tank I found under our vinery floor - see pics half way down here...
http://www.periodproperty.co.uk/forum/viewtopic.php?f=1&t=7478&st=0&sk=t&sd=a&hilit=vinery&start=15

 

[spot]

Excellent! Another source of water for the garden in case we ever do get the droughts they promised 3 years ago
I think I'll clean out the roots and the muck on the bottom and then stick a hand pump on top.

 

[Flyfisher]

A cess pit/pool requires regular emptying and has NO outlet (or shouldn't!) while a septic tank "treats" the sewage to an extent then allows the liquid to flow out into the soil or water course.

Thanks for that clarification. Ours is a septic tank then, because it shows no sign of needing to be emptied.

 

[Schoolmarm]

A cess pit/pool requires regular emptying and has NO outlet (or shouldn't!) while a septic tank "treats" the sewage to an extent then allows the liquid to flow out into the soil or water course.

Thanks for that clarification. Ours is a septic tank then, because it shows no sign of needing to be emptied.

Not necessarily. A damaged/broken septic tank will also show no signs of needing emptying.

 

[DaveBrigg]

Not necessarily. A damaged/broken septic tank will also show no signs of needing emptying.

A septic sceptic...

 

[Nemesis]

A full septic tank looks much the same re water level as one which isn't. It's the level of sludge which requires monitoring.

 

[L1zzy]

I had one of these tanks at the far end of the garden to my 1930's bungalow - never did find out what it was - it regularly filled and emptied of water of its own accord . I too figured it was related to storage of water - drainage from guttering was into soakaways nearer the house and soil waste thankfully went somewhere else. (My mystery tank actually contained a bicycle as well...yes a rusty BiCYCLE!!!)

 

[Feltwell]

I've heard the theory that rainwater was softer than that from the well, and so better for washing clothes.

That would be my theory as well, especially as you say you know where the cess pit was. The National Trust has a property called Sunnycroft, very close to my house, built about the same time as yours. It's a "time capsule" kind of property - architecturally nothing very exciting, but almost completely unaltered since it was built and with nearly all it's original contents.

That has a rainwater tank in the ground just outside the kitchen, which the guide says was used for collecting "soft" water for washing clothes and dishes with - much easier to get a lather with soap with soft water than hard water.

I can see the sense in it - in my last house the water was so hard we fitted a water softener, it made a big difference to how soft our clothes were. My baby daughter had been having problems with dry skin, as soon we fitted the softener it cleared up completely.

 

[Aidan]

They were called cisterns, usually waterproofed with puddled clay. I have a diagram somewhere in an old book. Cess pits were constructed in a similar manner. They usually had vaulted brick roofs until concrete became available.

They usually take the run-off from the roof drains. You could confirm that by putting a hose into the gutters and seeing if it starts to fill up; unless the drains have since been rerouted. The high-level pipe is probably an overflow connecting to a soak-away or a drainage ditch. Think of it as an underground water butt. There should be a small pipe, probably lead, that connected to a hand pump in the house.

 

[Penners]

Cesspit or freshwater sump - your nose should be able to tell you which!