Australia’s water challenge

For Australians, and especially for younger generations, “drought” and “floods” are words that have entered everyday’s vocabulary. The atmospheric disruptions that have affected the country in recent years have forced the majority of the population to reckon with water, its scarcity, and its excesses.

According to a study conducted in 2020 by the Australian Institute for Disaster Resilience and World Vision, the most extensive consultation ever carried out on young people, climate change, and its risks, over 90% of the respondents have experienced an extreme weather event in the last three years.

On one hand, there have been floods due to heavy rainfall, and on the other hand, water shortages and devastating fires caused by drought. Australians are now well aware that the climate is undergoing profound changes, and new measures to manage such a precious resource as water have become more urgent than ever.

The significant drought of 2009, when water reserves in major dams reached a critical level of 25%, seems like a distant memory for the capital of Victoria state. Recent summers, thanks in part to the La Niña weather phenomenon that has been affecting the Australian East Coast for several seasons, will be remembered as some of the rainiest in decades.

The heavy rains have helped fill the artificial basins of dams almost to the brink. The average water storage is around 95% of their total capacity, with the Thomson Dam, the city’s largest water resource, reaching 98% of its load capacity. However, this seemingly positive figure conceals a risk for the large infrastructures: the possibility of water overflowing beyond the containment basins. This risk has prompted Melbourne Water, the city’s water authority, to take action on multiple fronts. On one hand, they have activated a series of secondary basins to redirect the excess water into the large artificial lakes of Thomson, Upper Yarra, and Cardinia (three of the region’s most important dams). On the other hand, they have requested the state government to cancel the rest of the annual water order that was agreed upon with the Wonthaggi Desalination Plant, an infrastructure built to address the risk of drought and inaugurated in 2017.

However, seasonal rains are not sufficient to mitigate the prolonged effect of reduced atmospheric precipitation. Consequently, the state government has still urged citizens to reduce their average water consumption to 150 liters per person per day, compared to the current 159 liters, and significantly less than Sydney residents’ average of 200 liters. Melbourne Water has also reminded everyone that if weather conditions similar to those experienced between 2006 and 2009 were to recur, it would take only 12 months to return to critical levels.

In New South Wales, the state where Sydney is located, the available water is insufficient to meet the needs of numerous agricultural activities. Particularly in the western regions of the state, farmers have been complaining for months about the inadequacy of water supply and have been urging the state to expedite the Wyangala Dam expansion project. The project involves raising the dam’s embankment wall by an additional 10 meters, increasing the artificial lake’s capacity by 50%.

This project aims to not only expand the size of the reservoir but also secure the management of excess water, which, in recent months, has caused significant damage to farmers due to flooding resulting from heavy winter rains. “The New South Wales – stated Bev Smiles, spokesperson for the Inland Rivers Network – really needs to look closely at its dams management policy both for critical needs in extreme drought… and the way they currently manage dams to keep them full as much as possible.”

Proper water management ensures not only water supply for the major Australian cities but also for energy production. Alongside investments to improve dam operations and storage capacity, the country is investing in facilities capable of producing energy from water, taking a sustainable approach to meet the demand for electricity. This is the aim of the mega Snowy 2.0 project, currently under construction in the Snowy Mountains in New South Wales. It is the largest “green” energy project in Australia, developed by a joint venture led by the Webuild Group, which includes the construction of an underground power station and a system of hydraulic tunnels connecting two existing dams.

When there is excess energy production and, consequently, low energy demand, the plant pumps water from the lower dam to the higher one. Conversely, when the demand for energy increases, the water is released downhill, generating electricity. This way, significant fluctuations in energy supply in the country, which occur when wind and solar power cannot meet the energy demand, are reduced. In numbers, Snowy 2.0 will increase the previous plant’s capacity by 2,000 MW, providing 350,000 MWh of large-scale storage, sufficient to meet the needs of 500,000 households for over a week of peak energy demand. This approach allows for the sustainable use of water, never wasting such a precious resource.