Case study: Water re-use and harvesting scheme

Several years ago, The City of Salisbury developed a major stormwater harvesting scheme that focused on the Parafield Airport and surrounding catchment area to provide cleansed stormwater to Michells, an Australian wool processing company. The city began harvesting stormwater from the Parafield Airport catchment and delivering it into capture basins and a reed bed lagoon constructed under specially designed bird-proof netting. The reed beds biologically cleanse the water that would otherwise flow, full of pollutants, into the sea. Once cleansed, the stormwater was supplied directly to Michells with any surplus supply injected into an underground aquifer for storage. When required, the cleansed water was extracted from the aquifer using submersible borehole pumps.

However, such is the rapid pace of residential, industrial and commercial development that it soon became apparent that the scheme should be extended to provide non-potable water to multiple users, including Mawson Lakes – a rapidly expanding housing development.

The council sought the advice of Grundfos dealer, Asset Mechanical Engineering – which had assisted with the initial water harvesting scheme.

The expanded scheme saw the installation of six-pump manifold Hydro 2000 Pro booster system, initially equipped with four CR90-3, 22 kW pumps.

Using Grundfos controllers and software, the CR90-3 pumps, which work on demand at between 0-20 L/s and 600 kPa, deliver recycled stormwater to the rapidly expanding customer base of the Parfield aquifer storage and recovery (ASR) scheme.

The scheme also supplies recycled stormwater to the Mawson Lakes recycled water system, where it is mixed with treated wastewater from the Bolivar wastewater treatment plant. The recycled water is then pumped into Mawson Lakes via a separate reticulation system and used to water gardens, wash cars and flush toilets.

The water harvesting system, using Grundfos pumps and controllers, will supply more than 1500 ML of recycled stormwater to a wide range of users within the City of Salisbury area.

Water Fast Fact
Aquifer storage has many potential advantages over surface water storages such as dams and reservoirs. Aquifers can store large quantities of water without losses from evaporation and with reduced risk of contamination, both of which are problems associated with surface water storages. (Source: Australian Bureau of Statistics)

Grundfos Pumps Pty Ltd
www.grundfos.com