PURIFIED RECYCLED WATER FOR DRINKING (PRWD)
Purified Recycled Water for Drinking (PRWD) is the treatment of water for use in the water supply distribution system. This can be by the injection of recycled water directly into the drinking water supply distribution system downstream of the water treatment plant or into the raw water supply (dam, river, reservoir or aquifer) immediately upstream of the water treatment plant.
The Western Corridor Recycled Water Scheme (WCRWS) is an example of a Purified Recycled Water scheme in Australia. Located in South East Queensland, treated wastewater is sent to advance water treatment plants at Bundamba (west of Brisbane), Gibson Island and Luggage Point (in Brisbane’s east). At the plants, treated wastewater is filtered and then passed through a number of processes including membrane filtration, reverse osmosis and ultraviolet advanced oxidation to produce purified recycled water. The purified recycled water is then pumped to Wivenhoe Dam, where it blends with rainwater runoff stored in the dam. Water is then treated again at water treatment plants downstream at Mt Crosby, before being delivered to homes and businesses. The advanced water treatment plants can produce about 180 million litres a day or 20% of current demand. The scheme is currently in ‘care and maintenance’ mode, as the drinking water dam levels are high and purified recycled water is currently not being pumped into Wivenhoe Dam. Under South East Queensland’s Drought Response Plan, the advanced water treatment plants will be brought online when the combined levels of the drinking water dams reach 60% of their capacity.
Further information on PRWD can be found at:
● Direct & Indirect Portable Reuse - A United States Perspective (Webinar)
● The Future of Potable Reuse (Podcast)
● ATSE: Drinking Water Through Recycling - The benefits and costs of supplying direct to the distribution system (report)
● Would You Drink Recycled Water? (ABC radio)
● Seqwater; Purified Recycled Water (fact sheet)
Aquifer / Groundwater Recharge
Aquifer / groundwater recharge are manmade processes or natural processes enhanced by humans that convey water underground. The processes replenish ground water stored in aquifers for beneficial purposes. Managed aquifer recharge (MAR) is the intentional recharge of an aquifer under controlled conditions for later recovery, environmental benefit, or to mitigate the impacts of abstraction.
In Perth, Water Corporation's groundwater replenishment scheme uses treated wastewater to supplement Perth’s drinking water supply. The scheme is Australia’s first full-scale groundwater replenishment scheme and is in Perth’s northern suburbs, in Craigie, Western Australia. It started recharging recycled water to Perth's deep aquifers in 2017. In the scheme, treated wastewater is further treated to drinking water standards and recharged into our groundwater supplies. The water can then be stored in underground aquifers, which store and naturally filter the water until it is needed. Currently, groundwater replenishment makes up 3% of the Integrated Water Supply Scheme, which services over 2 million people in Perth, The Goldfields and Agricultural region and some parts of the South West.
Further information on MAR can be found at:
● WA Government: Managed Aquifer Recharge
● Water Corporation: How we replenish the groundwater supply
● CSIRO: Managed Aquifier Recharger - Frequently Asked Questions