Please help. I have spent all day clearing my drains following a back up
into one of my loo's ( I have two, one out which was OK, and one in bathroom
, not OK!).

I have been led to believe that I have a septic tank system.. When I couldnt
get the second manhole to clear I lifted the cover on the septic tank to
see if the problem was there , looking for the rodding point like it says in
the diagrams in all the books.

I am new to septic tanks and dont actually know what its supposed to look
like.

However, mine does not look like the diagrams. It is brick built , oblong,
5ft x5ft and very very deep it would seem, at a guess 20 ft deep.
There are no visable inlet or outlet holes, no rodding t points, no vents
and no baffle between two chambers.

I can see some vertical slits like the slats of a ventilator in the brick
work at the water level. Not sure what those are. Cant find anything like it
on a diagram of a septic tank online.

Whether it even has two chambers and I have opened the inspection hatch to
the first only I do not know. I can only see this one.

I have managed to clear the intercepter drain into the tank but still
cannot see an inlet point from the drains system.. I am guessing its below
the water line.

Is this a septic tank?

I have a bungalow built about 1956 in Devon ( I state the location because
I have found from experience that often things here are different to other
parts of the country) on a smallholding. No mains connections available.

No recorded problems with this sytem as far as I know. I have not had a
problem with my drains until now.

No stinks no other symptoms of problems.

I am thinking of draining it to see if I can find the inlets but water level
is at least 13 ft down the hole. Depth of water/ deposits / silt I estimate
to be about 4 ft at the bottom.

I am not sure if my land drain is blocked?

Indeed will there be a land drain and if so which way is it likely to be
running? No plans to go by. Original plans of house say septic tank and
show it as two boxes , but the whole thing seems to be further over in the
original plans than the siting of this box.

No other manholes visable ( all grass area)

Anyone have something similar? Anyone seen anything similar?