The LCD fact of the month is related to how much carbon emissions is associated with household water use and treatment. The ratio varies between cities in Australia and globally.
How much CO2e is associated with water?
Perth has been served with traditional water sources from shallow groundwater and dams, and since 2006, Perth became the first Australian city to operate a reverse osmosis seawater desalination plant, the Kwinana Desalination Plant, where the water from the ocean flows through the membranes to extract all of the salt. Pumping required for desalination and distribution is very energy intensive so by the time you use the water there is a lot of embodied carbon in it, as outlined in the fact above. The water treatment process also requires additional energy for pumping and filtration further increasing the amount of embodied carbon per kL of water. Energy sources used in water supply and treatment include electricity from coal and gas, and renewables. Increased efficiencies with less water use, higher use of recycled water and use of renewable energy are all part of the plan to provide sufficient water sustainably.