On 26/05/17 14:47, NY wrote:
"The Natural Philosopher" wrote in message
news
If, by septic tank, you simply mean a bloody great tank full of ****
that does no treatment whatsoever, then of course you are right,
because it has no outflow and must be emptied - generally every monthh
or two - by a truck and a pump. Of course since there are no bugs to
kill you can sling what you like in it.

OTOH if you are talking about a private sewage treatment plant with
settlement tanks that use the actual bacteria to digest the **** into
acceptable fertiliser and purify the water that is then discharged on
a continuous basis, then of course they are ALWAYS FULL of water.

As far as I am aware, the first is called a cesspit and the second is
called a septic tank.


That is my understanding also.


My parents have a septic tank (well, the standard arrangement of two
enormous round-bottomed flasks in the ground, where one drains into the
other) at their holiday cottage. Admittedly it doesn't get as much use
as a family house that is lived in all the time, but as far as I know it
has never been emptied in the 40 years that they have owned the cottage.
The treated outlet flows into the communal rainwater drain that is
shared by all the houses in a terrace and eventually flows into a nearby
stream. I presume all the other houses' septic tanks do the same.

Funny story: when we bought the cottage, it had been badly modernised on
the cheap. It had the septic tank but we also found a huge breeze-block
lined chamber, with no roof on it (just a huge hole in the ground) in
the back garden. There was a T-shaped sewer pipe protruding from the
side of one wall in the chamber. It had never been used. We tried to
work out why and I did some measurements and concluded that the outlet
into the tank was a foot or so *higher* than the downstairs loo. I
wonder if the previous owners actually connected up the pipes and tried
to use it, only to discover that sewage doesn't flow uphill, and then
abandoned it and had the septic tank installed instead.

Why is it that owners of septic tanks are warned not to use plungers
(only rodding) to clear any blockage?

No idea. I rodded all mine cos thats all I had



--
Canada is all right really, though not for the whole weekend.

"Saki"