|
This page provides basic information for
occupiers of premises served by Aerobic Systems to help them
understand the system and ensure its correct operation and maintenance to prevent risks to
health and safety or nuisance conditions.
There are
basically two types of aerobic systems . . .
- aerobic wastewater treatment units,
- aerobic sandfilters.
What is an aerobic wastewater
treatment unit?
An aerobic wastewater treatment unit is designed to treat
septic tank effluent to a level suitable for surface irrigation within the site.
The unit may incorporate a septic tank or it may be
separate.
Following primary treatment in the septic tank, the
effluent is treated by a process of aeration, settling and disinfection and then pumped to
a dedicated irrigation area as reclaimed water.
What is a sand filter?
Sand filters achieve a similar result to aerobic
wastewater treatment systems but the treatment process is different.
The effluent from the septic tank is filtered through a
sand layer which provides natural aeration and biological oxidation through aerobic and
nitrifying organisms.
From the disinfection chamber the reclaimed water is
pumped to the dedicated irrigation area.
Aerobic systems
Both types of treatment achieve a level of water quality
that permits the discharge of the reclaimed water to surface irrigation within a dedicated
landscaped irrigation area.
Before an aerobic system can be installed, an approval
must be obtained from the local council, or in some cases the
Department of Health.
The approval specifies the plumbing and drainage layout,
septic tank, aerobic system and location of the dedicated irrigation area.
The occupier of the premises should have received a
comprehensive manual on the care, operation and maintenance of the aerobic system when it
was installed.
As a condition of approval, the occupier of the premises
served by an aerobic system must maintain the system to ensure that reclaimed water
complies with safe water-quality standards.
If the aerobic system is not correctly maintained
it may create health risks for the occupants.
WARNING: To prevent injury or drowning the access
covers for the septic tank and aerobic system chambers must be securely fixed to prevent
access by children. Access should only be by service personnel. Damaged covers must be
replaced and securely fixed in position.
|
Operation & maintenance
|
A correctly operated and maintained aerobic system
provides the occupants with a safe means of re-using reclaimed water without risk to
health and helps conserve water.
Servicing
Aerobic wastewater treatment units and sand filters must be serviced by the system
manufacturer or an accredited service agent at 3 monthly intervals or as recommended by
the manufacturer in the service manual.
Maintenance, depending on the type of system, may include checking the blowers, contact
media, pipework, valves, diffusers, effluent clarity, sludge return, removal of excess
scum, testing the pump and general operation of the system.
A supply of chlorine tablets sufficient to last until the next scheduled service must be
installed in the unit.
|
Septic tank pump-out
The septic tank needs to be pumped out every 4 years or more often according to approval
conditions.
Pumping out of the septic tank must be done by a licensed contractor.
Alarm
All aerobic systems must be provided with an alarm system to alert occupants to an
electrical or mechanical malfunction.
The alarm must have an audible and visual (indicator light) component with muting for the
audible alarm.
The fault indicators should be located inside the premises preferably within the kitchen
or laundry or other location.
Odour
Slight odour from the system is normal. However, strong persistent odours indicate the
system is not functioning correctly.
Irrigation system and irrigation area
Remember that the dedicated surface irrigation system and irrigation area must function
every day of the year - rain, hail or shine.
When setting up the irrigation system, the following points should be considered:
- a typical residential dwelling will require 200m² of land
for the irrigation area. Larger or commercial systems may require larger areas,
- the irrigation area must comply with setback distances
from the building, boundaries, swimming pools etc,
- the irrigation area must be landscaped with suitable salt
and nutrient tolerant plants,
- the irrigation area must be designed to discourage or
prevent access by people, pets or vehicles,
- the reclaimed water must be evenly distributed over the
whole area without spray drift, pooling or run-off. On some sites it may be necessary to
install drippers,
- the irrigation system must not be connected to the
reticulated mains supply or other drinking water supply,
- all distribution pipework for the irrigation system should
be buried at least 150mm below the ground surface,
- the reclaimed water is not to be used for growing food
crops,
- roof and surface waters must be diverted away from the
irrigation area,
- the irrigation area must not be located on land subject to
flooding or waterlogging,
- the irrigation area should have precautionary signs placed
on all sides worded as follows:
Warning - Reclaimed
water,
not suitable for human contact/consumption
The signs should have a white background with
red
lettering of at least 20mm in height,
- the pump provided in the aerobic system must be of
sufficient capacity to ensure an even distribution of reclaimed water to the whole of the
irrigation area.
Aerobic system manual & approval
conditions 
If you did not receive a copy of the operating and
service manual and the approval conditions when you moved into the premises, contact the
system installer or the manufacturer to obtain this information.
Note: This fact sheet is only a brief
guide to the basic requirements. For more detailed information on the installation,
operation and maintenance of aerobic systems refer to the South Australian Health
Commission Codes: Standard
for the Construction, Installation and Operation of Septic Tank Systems in
South Australia (PDF 340 Kb)
Further information can be obtained by contacting
the Environmental Health Officer at your local council or the Department of
Health. Go to the
Local Government website to locate the Council responsible for a
particular Town or Suburb.
Application Forms
Approved wastewater products list |
Standard Onsite
Wastewater Systems | Alternative Onsite
Systems |
Wastewater systems for towns and other large developments
| Pre-manufactured
products for sale and use in installations in SA |
Reclaimed Water Reuse
| Maintaining septic tank systems
| Wastewater Management
|
Seminar 2006 |
Seminar 2003
Return to top
|
