Aquifer Storage and Recovery

AGT has a focus on Artificial Recharge (AR) and Aquifer Storage and Recovery (ASR) techniques and methodologies.

ASR techniques have been used in many countries throughout the world, however ASR practice in many of these localities is restricted to spreading basin recharge to unconfined aquifers. The research and development which has been undertaken predominantly in South Australia over past years, in which AGT staff have been involved, has been unique in that it has focused on two important areas:

The injection, storage and recovery of stormwater and recycled water into unconfined and deep confined aquifer systems using deep well injection (greater than 100 metres).

Implications of wastewater reuse to deliver processed effluent for irrigation purposes eg vineyards.

Due to water shortages, demand for irrigation water is greater than the available supply, and in most of these areas the groundwater is also fully allocated. Treated effluent has a lower salinity than groundwater and is proving an important adjunct to supplies. Current approaches involve the storage of processed water in aquifers close to irrigation sites, so that supplies will be available when required.

AGT is represented by highly qualified and experienced personnel and is in the unique position to capitalise on their strengths, for the deployment of internationally competitive and technically innovative sustainable infrastructure solutions, for the benefit of its clients.

SO WHAT IS ASR?

An aquifer is geological material capable of storing significant amounts of water and transmitting it readily. There may be a series of aquifers lying one on top of another separated by non water-bearing beds.

Storage of water in dams and reservoirs during the wet season, for irrigation during the dry season, has long been used. Storage of water in an aquifer has the advantage of freeing up large areas of land, is more efficient as there is no evaporation of water and water is less susceptible to pollution.

Recovery of water from the aquifer through a well (or bore), for use during those dry periods is increasingly important as urbanisation and irrigation are placing increasing demands on our water supply.

The ASR process involves pumping excess storm water (or treated waste water depending on reuse purpose) into an aquifer for recovery and reuse when needed, thus providing water for parks, ovals and market gardens. Filling (recharging) the aquifer with excess storm water for later reuse enables sustainability of the resource rather than depletion.

WHY USE ASR?

ASR of storm water and wastewater has proven to be economically viable and ecologically sustainable. In South Australia many such successful schemes are in place. ASR has potential to:

provide the cheapest new source of water
put wastewater to productive use
develop emergency water supplies
protect aquifers from saline intrusion
improve groundwater quality
replenish depleted aquifers
reduce discharge of storm water/waste water into the marine environment
offset the costs of flood protection storage in urbanising catchments.

Guidelines have been written enabling appropriate environmental management plans to assure groundwater quality protection.