Pollution Control - septic tank and cesspit emptying
Septic tanks
Cesspools
Do's and Don'ts
of septic tanks
How the Council can
help
Septic Tank
A septic tank is a type of biological sewage treatment
system. Naturally occurring bacteria break down the solid
matter, reducing its volume. The liquid element is discharged
to a soil treatment system. The accumulated solids in the
septic tank need to be pumped out periodically (generally once a
year).
Septic tanks may be constructed in brick or blocks, although
modern types are pre-formed in reinforced fibreglass.
Where can a septic tank be sited?
Ideally septic tanks should not be sited close to houses.
Please contact Building Control for more specific advice, email
enquiries@nybcp.org . Not
all sites are suitable for septic tank systems. The main
concern is the type and porosity of the soil at the site.
Also the depth of the water table can be a problem if it reaches
too high a level in the wet season. Generally septic tank
systems cannot be placed in areas where the depth to bedrock or the
water table is less than 90cm.
What are percolation tests?
Percolation tests need to be carried out to ensure that there is
sufficient land to take the effluent away from a septic tank.
The tests should be carried out in accordance with BS6297 : 1983 to
determine the size of the effluent drains or soakaways, which must
be sited at least 6 metres from a water course. It may not
always be possible to install soakaways; soil conditions or other
factors such as ground water levels may make them
inappropriate. In this case you will need to consider some
other form of drainage. Before constructing soakaways it is a
requirement to obtain
"Consent to Discharge" from the Environment Agency. The
Building Control Partnership will also advise you on how to perform
the percolation test.
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Cesspool
A cesspool or cesspit is a sealed underground storage tank that
retains the sewage until the time of disposal. It may be
brick or block construction or manufactured in steel or reinforced
glass fibre and should have a minimum capacity of 18,000
litres.
Where can a cesspool be sited?
A cesspool should be sited so that there is no risk of polluting
water supplies and as far as practically possible from any
inhabited building.
Can a cesspool go wrong?
The tank can overflow or may leak which is an offence under the
1936 Public Health Act. In addition if it pollutes a
watercourse the Environment Agency may take legal proceedings under
the Water Resources Act 1931. This can lead up to a fine of
£20,000 and 3 months imprisonment.
If it leaks a drainage engineer should be called out to remove
the waste and clear up the sewage. The cause of the leak
should be identified and remedied.
How to avoid problems
Cesspools: check the level in the tank regularly, do not
let it overfill. Have it emptied at regular intervals: these
will become more frequent if you install a dishwasher for
instance.
Septic tanks: do not use excessive amounts of household
detergents or bleaches; these upset the biological balance of the
system. Do not overload the system by connecting rain or
water drains to septic tanks or cesspools.
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Do's
and Don'ts of Septic Tanks
Do
- have your septic tank system professionally fitted, following
local guidelines and regulations
- put all your wastewater from your home into the system
- know where your septic tank and drainage field are located
- have your system inspected regularly
- desludge the tank when necessary
- act immediately if you find a blockage or any sign of a
problem
- if necessary, seek professional help (see "Drain and pipe
cleaning, Plumbers merchants or Sewage consultants" in the
telephone directory)
- keep note of any maintenance work
- ensure all manhole covers are accessible
- ensure that any air vents are not blocked
- keep the drainage field protected
- divert sources of clean water, like roof drains, away from
septic tank systems
wash dishes in a dishwasher whenever possible (fat is converted
into soap in a dishwasher)
- use toilet fresheners, mild detergents, fabric conditioners and
washing powders and liquids in moderation without upsetting the
natural balance of the septic tank. All active ingredients in
soap and detergents should be biodegradable by law and should be
safe for septic tanks in normal use
- use bleaches and disinfectants sparingly – as they can kill the
friendly bacteria which make the septic tank work.
Don't
- fats, oils or heavy grease should not be poured down the
drain;
- paints, solvents and motor oils should not be put down the
drain;
- never dispose of garden chemicals and pesticides into the
septic tank;
- don't use the toilet or kitchen sink as a rubbish bin;
- don't empty chemical toilets into drains or septic tanks;
- nappies, sanitary items, plastic or similar items should not be
disposed of into the system – "bag it and bin it" instead;
- don't dig or drive over the drainage field, or cover it with a
hard surface;
- don't block air vents;
- don't desludge your tank too often;
- don't allow effluent to collect on the surface of the ground;
and
- don't enter a septic tank – dangerous gases are produced by the
natural treatment process.
Problems occur only very rarely, but should be remedied as
quickly as possible.
For a quotation for emptying your septic tank please contact
Streetscene by email streetscene@ryedale.gov.uk or
telephone 01653 600666 ext 481. For further information and advice
on septic tank health, please contact Environmental
Health by email envhealth@ryedale.gov.uk or
telephone 01653 600666 ext 256 or 257.
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How the Council can help
Advice on investigating complaints of nuisance from drainage
systems, leaking tanks or defective soakaways that require the
owner or owners to remedy the problem can be obtained by contacting
01653 600666 ext 256 or 257 or email envhealth@ryedale.gov.uk
. Failure to do so can result in legal action against the
person responsible under the Public Health or Building Acts.