MAR schemes vary significantly in scale.
The source and amount of water to be drained and the type of aquifer impacts on the complexity of the scheme. The scale of the scheme will also influence the amount of work that needs to be undertaken to design, develop and operate it.
Three categories of MAR schemes have been established to provide a guide to the amount of detail of different schemes. Note: this is a general guide only and depending on different circumstances, schemes may be more complex than initially indicated and require far more detail.
A domestic MAR scheme is where rainwater is collected from domestic dwellings, such as a house and sheds, through a closed system fitted with a first flush diverter, and drained directly to a suitable aquifer.
This type of scheme is seen as low risk to the aquifer system, as volumes are generally less than 500 kilolitres and subsequent extraction is unlikely. However, a strict set of criteria must be met and a drainage or discharge permit will be required.
If extraction of water is proposed and the property is within a prescribed area, a recharge extraction licence is also required.
Domestic schemes have the same obligations as commercial schemes to comply with the Environment Protection (Water Quality) Policy 2003. These include the obligations to protect the environmental values of the receiving aquifer. Non-compliance could lead to action by the Environment Protection Authority (EPA).
Small scale MAR
A small scale MAR scheme is where less than 20 megalitres per year of source water, such as stormwater or watercourse water, is to be drained to an aquifer.
The stage one assessment process may indicate that this type of scheme is considered low risk without preventative measures needing to be put in place. This is not to say that these schemes will not need scrutiny in the future.
The scheme must also comply with the Environment Protection (Water Quality) Policy 2003.
Large scale MAR
All other MAR schemes are classed as high risk and will be required to undertake the full four stage assessment process described in the MAR Guide.
These schemes will require collaboration between the Environment Protection Authority and the department, and will need preventative measures to be put in place and managed during the life of the scheme.
The viability and sustainability of a MAR scheme needs to be tested at a number of points during the process to avoid disappointment and unnecessary expense if it does not meet expectations.
Licence and permit requirements
MAR schemes that require approval via an authorisation through the Environment Protection Authority to discharge water to an underground aquifer are those:
- with a surface water capture area greater than one hectare within the Adelaide metropolitan area
- with a surface water capture area greater than one hectare within specified areas of the City of Mount Gambier
- utilising treated wastewater anywhere in the state
Note : if recharging treated wastewater to an aquifer, an exemption from the Environment Protection (Water Quality) Policy 2003 will be required if the receiving aquifer is deemed suitable, before the operation of a MAR scheme.
MAR schemes within metropolitan Adelaide that have a surface water capture area less than one hectare or surface water schemes outside of the Adelaide metropolitan area require a permit to drain or discharge.
All schemes that propose to extract the water in a prescribed area will require a licence to extract.
When developing a MAR scheme that will require an authorisation from the Environment Protection Authority, proponents must obtain a works approval or a development approval prior to the construction of the scheme, followed by a licence to operate the scheme. Proponents are required to submit two applications to the Environment Protection Authority:
- one for the works approval
- one for the licence.
The requirements for each submission and application forms are available from the Environment Protection Authority SA.