Draft Guidelines for Permanent Onsite Domestic Greywater Systems: Greywater Products and Installation

1 What is Greywater?

However, greywater may contain high levels of:

• Disease causing organisms (Bacteria, Viruses, Protozoa, Helminths).
• Suspended matter, organic matter, fats and oils, including but not limited to dirt, lint, food, hair, body cells and fats, and traces of faeces, urine, and blood.
• Chemicals derived from soaps, shampoos, dyes, mouthwash, toothpaste, detergents, bleaches, disinfectants, caustic dishwashing powders and other products (eg. Boron, Phosphorus, Sodium, Ammonia and other Nitrogen based compounds).

Management of greywater systems is essential to remove disease causing organisms, suspended and organic matter, as well as excess nutrients. Greywater systems can be separated into two types: Domestic Greywater Diversion Devices (DGDD), which divert greywater without storage or treatment, and Domestic Greywater Treatment Systems (DGTS), which collect and treat greywater to a higher quality, often with storage.

3 Approvals

Product approvals
Product approvals are required for devices that divert, treat or reuse greywater before they are sold and or marketed in South Australia. Approvals are issued by the Department of Health.

Installation approvals
Approved devices that divert, treat or reuse greywater require an installation approval from the relevant authority, incorporating product approval requirements, instructions provided by the product manufacturer, and any additional requirements (i.e. SA Water plumbing requirements). An application fee is charged for installation approvals and for inspections as required by the relevant authority.

Note: Installation of greywater systems must take into account the relevant authority’s requirements for setback distances. Note: For information on the temporary use of greywater including manual bucketing, see the factsheet – Manual Bucketing of Greywater.

4 Product Approval Requirements

• Where it is intended to install a greywater treatment/diversion system in a sewered (or other reticulated system) area, the system shall be capable of connection to the sewer (or other reticulated system) such that:
• Approval is obtained from the owner/operator of the system;
• An overflow to the environment will not occur should there be a failure of the greywater treatment / diversion system. The system (and any associated storage tanks) must be designed to provide automatic overflow to sewer (or other reticulated system); and
• The operator may manually direct greywater to the sewer (or other reticulated system) during periods of rain or other circumstances adverse to the discharge of treated greywater.
• Where it is intended to install a greywater treatment /diversion system in a non-reticulated area, the system shall be capable of connection to an effluent disposal system, as agreed in discussion with the relevant authority.
• The greywater treatment / diversion system must be designed to perform continuously and without any interventions between specified servicing intervals, performed by the maintenance contractor.
• The greywater treatment / diversion system must be constructed / installed in accordance with the design specifications, the relevant authority’s approval conditions, and in accordance with good trade practices so as to allow ease of access for maintenance and with regard to the health and safety of users, operators and persons maintaining the system.
• The greywater treatment/diversion system must be constructed so as to make appropriate provision for access to and removal of contents in a safe and sanitary manner (Refer AS/NZS 1546.1, Clauses 2.4.6 and 2.4.7 of 1998 version).
• Cross connection prevention controls shall be installed in accordance with AS/NZS 3500.1.
• An in-line strainer/filter is required and must be designed for easy removal of lint, hair and other larger particles.
• The greywater treatment/diversion system shall be capable of venting through the educt vent pipe on the house drainage system, or be separately vented in accordance with AS/NZS 3500.2.
• All components shall be securely fixed to withstand all loads encountered during the transportation, installation and normal operation.
• Untreated greywater must not be stored for more than 24 hours.

Plumbing and other SA Water requirements

Specific criteria for domestic greywater treatment systems (DGTS)

• The DGTS must be designed to treat the greywater stream for a minimum of 6 EP based on 100L/p/d (mains water supply).
• Any tanks and/or vessels and their lids used to contain the DGTS shall be accompanied by technical information supporting the design to the satisfaction of the Department of Health. Specific criteria for domestic greywater diversion devices (DGDD)
• No kitchen waste is to be diverted into the DGDD.
• Intallation instructions are to be provided on each unit for sale (including pipe material, diameter, orientation etc).

Product testing criteria for domestic greywater treatment systems

• The test DGTS shall be installed on a premises that is representative of a domestic greywater source, including all intended greywater source components such as laundry, kitchen, bath, shower and hand basins.
• Approval for installation and operation of the DGTS test site shall be obtained from the Department of Health.
• Test water is to be diverted to sewer (or other wastewater system) immediately after treatment and all required samples / tests have been undertaken. Permission must be obtained from the owner/operator of the sewerage (or other reticulated) system.

• Minimum flow requirements are continually received over at least the 26 week monitoring program. Average flows are to be +/- 20% of the nominated hydraulic capacity.
• Greywater to the DGTS is not to be absent for more than 3 consecutive days.
• Premises are to be occupied full time and on continual basis over the 26 week monitoring period.
• Premises and residents shall not be employees of, or associated with, the manufacturer, nor in any way connected with any company or individual associated with the manufacturer.
• The greywater influent to the DGTS shall be metered and readings recorded weekly.
• Appropriate diversion plumbing is made available in the case of DGTS failure, to either the sewer or other appropriate available wastewater system.

• The following are to be considered and included when selecting and setting up a test site:

• The manufacturer shall ensure that the premises are returned to its original condition, or to the satisfaction of the owner of the premises and the Department of Health, once testing has been completed.
• The test period for the DGTS shall be 26 weeks from the date of commissioning. The DGTS shall be commissioned in accordance with the manufacturer’s recommended procedure.
• The data described in Table 1 shall be obtained at the described intervals from grab samples collected over the 26 week monitoring period.

Table 1: Frequency of sampling

Other data to be recorded at a minimum interval of every 6 days includes:

• DGTS inflow reading;