Managed aquifer recharge
What is managed aquifer recharge?
Managed aquifer recharge is the intentional recharge of water to suitable aquifers for subsequent recovery or to achieve environmental benefits; the managed process assures adequate protection of human health and the environment.
There are a number of methods used to recharge aquifers including injection wells or infiltration structures such as ponds, basins, galleries and trenches. These methods help to reduce transport and storage costs and water loss through evaporation.
Water from a variety of sources can be used in the recharge process. These include water from watercourses, stormwater and treated wastewater.
Water quality
Natural treatment processes in the aquifer can improve the quality of the water. Some pre-treatment of the source water may be required to make sure that the quality of the receiving groundwater is maintained or improved.
The level of treatment needed for the source water generally depends on a risk assessment.
Purpose
The largest recharge project in Western Australia is the Water Corporation's groundwater replenishment scheme in Perth, which recharges high quality recycled water to boost future drinking water supplies.
Other purposes can include:
- reinjection of dewatering excess at mine sites
- storage and later abstraction for industrial or irrigation supplies
- sustaining of environmental flows in stressed surface or groundwater systems.
Managed aquifer recharge can provide an option for fit-for-purpose water supply in areas where water sources are limited.
Benefits
The benefits of managed aquifer recharge for water recycling are that it:
- generates additional water supplies from sources that may otherwise be wasted
- maintains wetlands in groundwater constrained areas
- stores recharged water to meet need in times of demand
- reduces the potential for salt-water intrusion
- increases water availability for commercial and environmental uses
- supplements supplies of drinking water.
Limitations
Managed aquifer recharge is only feasible if there is a suitable aquifer that can accept a sufficient volume of water at a sufficient recharge rate to justify the costs of establishing the project. It is not recommended if the environmental risks cannot be reduced to an acceptable low level - taking all costs and benefits of the project into account. Additional limitations may apply within public drinking water source areas and other sensitive areas.
Regulatory requirements
You can find regulatory requirements in the Managed aquifer recharge policy.
The document:
- details the department's requirements
- describes water quantity and water quality issues
- outlines the process for licensing
- provides information to support licence applications
- outlines the roles of other agencies.
Related publications
Guideline for the approval of non-drinking water systems in Western Australia