When water is intentionally placed and stored in an aquifer for later human use or to benefit the environment we call the process a managed aquifer recharge (MAR) scheme.
MAR schemes help replenish depleted aquifers (underground reservoirs) and are a way to store precious water until it is needed at a later date. In times of low rainfall, for example, water that has been stored in an aquifer can be pumped to the surface to contribute to domestic water supplies or to restore healthy river flows.
Find out how to plan, build and operate a MAR scheme or about MAR regulations.
Significant projects in South Australia
How do MAR schemes work?
MAR schemes can be set up using river water, stormwater, roof runoff, treated wastewater and other types of water sources.
Many organisations, such as councils and golf clubs, use MAR schemes as a way to improve their water security. They are able to store excess water in winter and recover it in summer when irrigation needs are greater.
For a MAR scheme to be feasible, you will need:
- a suitable source of water
- an ability to adequately treat the water to a suitable quality to meet guidelines
- an appropriate aquifer in which to ‘recharge’ the treated water
- a potential end use if the water is to be extracted
Aquifers can be recharged in several different ways, including:
- Aquifer Storage and Recovery, where water is stored in an aquifer and later recovered for use
- Aquifer Storage Transfer and Recovery, where water is injected into an aquifer through one well and later recovered via a different well
Check out CSIRO’s fact sheet for more examples of the ways in which MAR schemes can be recharged.
Find out about different scales of MAR schemes, ranging in size from single-house to regional, or see the step-by-step stages of a MAR scheme.
Are there any risks?
MAR schemes have the potential to attract many hazards and difficulties. It’s essential that their planning, design, construction and operation is carefully thought out and managed.
Typical examples of the pitfalls to the establishment and operation of a MAR scheme include:
- a highly variable and unreliable supply of source water
- the absence of a suitable, local storage aquifer
- an inability to recover recharged water due to aquifer properties
- insufficient land for harvesting or pre-treatment of water prior to recharge
- the contamination of recharged water due to geochemical interactions in the aquifer
- the contamination of aquifer due to inadequate quality control on recharge water
- a non-competitive cost benefit of scheme
- delays or restrictions put in place by regulatory bodies in the commissioning and operation of the scheme.