Adelaide has always had problems with water security, ever since its establishment by British settlers in 1836. In the mid-19th century the growing population came to the realisation that the small Torrens River couldn’t fulfil Adelaide’s rapidly growing demand for water. Although reservoirs were built, Adelaide’s water supply still couldn’t cope with the increasing demand. So in 1955 Adelaide started to pipe in water from the Murray River (over 60 kilometres away), but this was a temporary solution.
The use of the Murray River has now become a source of contention and Adelaide is once again on the search for a new, sustainable source of water. In 2012 the South Australian government constructed a AU$1.83 billion-dollar (€1.18 billion) desalinisation plant in Lonsdale, just south of the city. It has the capacity to produce 100GL of clean water per year. In 2019 the South Australian government decided to increase water production at the desalination plant to 40GL of water per year in aid of drought relief. This figure may rise to 60GL in 2021.
Although this may seem like a solution to water scarcity, this plan has three large problems;
- The plant doesn’t have the capability to produce enough water to satisfy Adelaide’s water demand. At the moment Adelaide’s desalination plant supplies around 4% of Adelaide’s water demand, but even if the plant is running at maximum capacity (100GL per year), this would only satisfy half of Adelaide’s water demand. Therefore, Adelaide will be forced to continue using unsustainable, alternative water sources such as the Murray River.
- Desalination is expensive! According to SA Water’s 2016 report, water costs AU$0.95/m3 (€0.61) to produce in Adelaide’s desalination plant. This is more than 9 times the global average for ground water extraction. Because of this, the South Australian government is unwilling to make desalination the main source of water in Adelaide because it’s economically unsustainable.
- Desalination has negative environmental impacts. Desalination plants require the burning of fossil fuels for energy, and they produce brine as a by-product that may harm marine organisms and coastal water quality. Since the negative environmental impacts of water extraction from the Murray River is one of the reasons why Adelaide wants to reduce its reliance on the Murray, it doesn’t make any sense to switch to desalination instead, as that also damages the environment.
Adelaide will not be able to rely on desalination to quench its increasing thirst, so What’s the solution? Should they focus on recycling waste water or fixing leaks or lowering demand through price increases? In reality, this question is very difficult to answer and I’m sure that if there was one simple solution, Australia would already be doing it.
Bottom Line: Desalinisation is not a permanent solution to Adeaide’s water scarcity.
* Please help my Water Scarcity students by commenting on unclear analysis, alternative perspectives, better data sources, or maybe just saying something nice 🙂