"John" wrote in message
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"Peter Scott" wrote in message
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"MM" wrote in message
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I recently moved on to a brand-new estate which has a privately run
sewage treatment plant, completely separate from the water company for
this area. There was supposed to be a management company set up to run
this plant, but it appears to be going pear-shaped, with volunteers
pulling out, a mounting debt, and certain individuals complaining to
the point of having their solicitor write a letter.

Does anyone know what these small estate-based sewage treament plants
typically cost to run? I have been told the plant here needs emptying
three times a year. The development contains approximately 40
dwellings, and all residents pay a proportionate amount.

In another part of the village, houses are also connected to a similar
local sewage treatment plant, yet that one is entirely run by the
water company, as if one were on mains sewerage and simply paid the
water and sewage bill. Perhaps it would be best if 'our' proposed
management company simply transferred (sold?) the plant and the
responsibility for running it to the water company?

Not sure if this will help. I have an Entec plant with a capacity for
ten
people.
An annual service costs about UKP150 and emptying twice a year about
UKP60. The cost to install a new one in place of the existing one would
be
about UKP5000. The plant serves just my house.


Is that the type with rotating discs which the bacteria colonise as they
digest the various biological materials in the tank?
AIUI they consume the digestible part of the liquor eventually leaving a
clear liquid outfall which is supposed to be acceptable for discharge into
the ground drainage. How does this differ from a traditional septic tank
where moving parts are not required? (Except in size, needing a power
supply, and a mechanical maintenance requirement) We had a traditional
septic tank for many years and I recall it needing emptying about once
every
ten years as the undigestible sediment in the tank built up very slowly.
Our tank served a household of five and did not cause any problems as to
smells etc. We used to chuck a dead rabbit in when it was emptied as a
starter for the bug colony but country lore used to say a dead cat was the
idealg
As we had a septic tank we got a reduction in water bils so it paid for
itself as to emptying charges


My plant has three tanks. The first traps the solid matter and has to be
emptied
once a year usually. The foul liquid then flows into a second tank where it
stays
for some time. Away from the plant I have an air pump. This pushes air
through
a plastic pipe. This goes to the bottom of the second tank and bubbles up
into
a vertical pipe about 4 cm dia. The bubbles carry the foul liquid with them.
The
pipe forms a 'T' at the top. Each branch has a spreader cone on it. This
splashes
and spreads the liquid across two filter beds each about 30 x 50 cm. The
water
trickles down the beds and is purified. The other function of the air is to
oxygenate
the water for the filter beds. The 'clean' water then flows to a third tank
where it
is stored before flowing out to a stream. The Environment Agency is allowed
to
test it for purity. The whole plant is about 2.5 m cube and mostly
underground.
I like the fact that no electricity has to be run to the plant. The middle
tank is by
far the biggest.

Unless it is an existing system you may not use a septic tank unless you can
prove that the sub-soil will allow the soakaway to drain freely. You dig a
30cm
cube hole, fill it with water and time how long it takes to drain. Existing
'illegal'
systems can remain unless they start to cause pollution or excessive smells.

Taking the original install cost of UKP2500 and annual running costs into
account I reckon I've better than broken even with Anglian Water high
charges.

Peter Scott