Eastern Australia: Desalination Plants Could Relieve Pressures from Increasing Urban Water Demand

22 August 2018 Madeleine Lovelle, Research Analyst, Global Food and Water Crises Research Programme

Background

Large parts of Australia are either suffering from drought, or are experiencing drought-like conditions. Following autumn 2018, which was the country’s fourth-warmest on record, July has been the driest month nationally since 2002.  New South Wales, north-west Victoria and eastern South Australia are experiencing the worst drought conditions, with low water levels affecting not only regional areas, but urban ones also.

Comment

Victoria is currently experiencing one of the driest winters since the millennium drought, which ran from 1996 to mid-2010. With Melbourne’s current water storage levels at 59 per cent, the city’s water governing body, Melbourne Water, has advised the Victorian Government to order 100 gigalitres of desalinated water for 2019; a quantity that would meet almost a quarter of the city’s demand. The desalination plant was completed in 2012. In 2017, the Victorian Government began a three-year trial that involved ordering a minimum of 15 gigalitres of water from the plant each year. The government has continued to order the minimum amount in an attempt to keep consumer costs low, while attempting to ensure the continuity of the city’s water supply. The effects of the drought conditions have now led Melbourne Water to increase substantially the recommended quantity.

The Victorian Government has so far made no commitment on the size of its next order. It has stated that the decision will depend on dam levels, as well as the price that households and businesses will eventually end up paying. In 2016-17, Melbourne consumers paid $6.70 per kilolitre of water, making it the third-most expensive capital city (by comparison, the top price for water during the same period was in south-east Queensland, at $8.90 per kilolitre). Victorian authorities argue that if a greater quantity of desalinated water is ordered, prices are likely to rise even further.

In Sydney, record-low rainfall has caused the city’s water storage levels to drop to two-thirds of total capacity. July 2018 was the driest July since 1995 and the water level in the Warragamba Dam, Sydney’s largest, has dropped by 25 per cent in the last year. Increasing water consumption added to the effects of Sydney’s scarce rainfall patterns over the past 12 months, have sparked discussions about whether the city should restart the Sydney Desalination Plant. Construction of the plant was completed in 2010, yet it has never been used to produce desalinated water for the city’s supply network.

Despite the city’s decreasing water supply, there are concerns that the Sydney Desalination Plant will not be ready for use if, as predicted, water storage levels fall below 60 per cent in under three months’ time. The plant was damaged during a storm in 2015 and repairs have been delayed by a dispute between its operator and the insurer. Several years ago, construction of the desalination plant was criticised by some for being a “panicked” response to falling Sydney water levels, which were originally thought to be on track for recovery. Now that the state is experiencing another severe drought, it may be time to rely on Sydney’s “insurance policy” to alleviate water shortages.

With the exception of Perth, the cost of running desalination plants has frequently been cited by governments as a reason to avoid relying on them. Given Australia’s current dry conditions, however, it seems that time is running out for that approach. Soon, governments will have no choice but to rely on desalination unless weather conditions improve rapidly. The effect of producing more desalinated water is unlikely to benefit regional areas currently struggling with drought conditions. For urban areas, however, the additional cost of using desalination may be outweighed by the need to supplement current water supplies in metropolitan dams.

Any opinions or views expressed in this paper are those of the individual author, unless stated to be those of Future Directions International.

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