The rapid advancement of artificial intelligence has triggered an unprecedented surge in demand for computing power. This growth is so immense that hyperscale data centres, each comparable in size to a football stadium, are now being constructed across Australia.
The Scale of the Problem
A single rack of servers within a data centre can easily consume more than 30 kilowatts of power—exceeding the typical energy usage of an entire household. These densely packed electronic systems are voracious consumers of electricity, which inevitably generates enormous amounts of heat.
That intense heat must be dissipated; otherwise, the electronics will fail. Traditional air cooling methods are no longer sufficient for modern data centres. Cooling represents one of the largest operational costs, accounting for up to 40 percent of total energy consumption.
Cooling Options: Energy vs. Water
Data centres have two primary cooling methods: energy-intensive or water-intensive systems. Given current economics, the choice is clear. Drinking-quality water remains relatively inexpensive, while electricity is costly. Consequently, these colossal heat generators become immense water users.
When multiplied across Australia, this adds pressure to already over-exploited water resources. The nation currently hosts more than 250 data centres, with many more planned. Proposed data centres for Melbourne's western suburbs could consume as much as 20 gigalitres of water every year.
To put that into perspective, the Maroondah Reservoir, a critical dam in Melbourne's water supply, holds just 22 gigalitres. Such demand will worsen the already strained water supply for Melbourne's rapidly growing population, forcing Victoria to extract more water from rivers and groundwater.
Sydney faces a similar situation, with data centre water demand forecast to reach 250 megalitres per day by 2035.
Beyond Consumption: The Effluent Problem
This issue extends beyond simple water consumption. Data centre cooling towers use chemicals to prevent corrosion, maintain cleanliness, and control biological growth. These towers accumulate salt, metals, and nutrients.
When cooling towers are flushed, the wastewater is discharged into sewer systems. This adds to the toxic load entering rivers and marine environments already stressed by effluent. The environmental consequences are often treated as an afterthought, as if aquatic ecosystems hold no value compared to the human economy.
Both aquatic life and human communities depend on healthy water systems that are already overstressed by climate change and human demands. Further reductions in water flows will have profound impacts.
A Path Forward
Part of the solution involves rebalancing the economic equation by making high water usage in data centres more expensive. The alternative is inaction until water becomes so scarce that households and other businesses effectively subsidise data centre operations.
David Tiller is an aquatic pollution ecologist. The Fuzzy Logic Science Show airs at 11am Sundays on 2xx 98.3FM. Send your questions to AskFuzzy@Zoho.com; Podcast: FuzzyLogicOn2xx.Podbean.com
