Conflicts over water have raged throughout history, but its growing scarcity is creating fresh tensions around the globe.

Forget gold, oil, coal or any other commodity extracted from the ground, water remains easily the world’s most precious resource.

It is, after all, the building block of life. We use it to produce food, to power cities and even for recreation.

But although more than 70 per cent of the Earth’s surface is covered by water, just 2.5 per cent of it is fresh.

Such scarcity, when coupled with a rapidly growing population placing greater demand than ever before on freshwater, presents the world with an almighty challenge.

By some estimates, more than one billion people already do not have regular access to reliable and pollution-free sources of freshwater.

And as man-made climate change compounds the natural vagaries of the weather, the delicate balance between freshwater supply and demand is threatened.

At a time when self-interest in international relations has rarely been as pervasive, the risk of conflicts breaking out is heightened. Can we trust our governments to act in the best interests of the global community when it comes to managing this finite resource?

So parochial does management of freshwater become that it has even brought states within the confines of federal boundaries to the brink of war. In the 1930s, the US state of Arizona deployed a makeshift navy to patrol the Colorado River as tensions escalated between it and California over water arrangements.

And only a few short years ago, the states of Queensland, NSW, Victoria and South Australia engaged in a bitter brawl over the management of the all-important Murray-Darling Basin system.

Revelations yesterday that at least 13 towns across central Victoria face water restrictions in the coming months should come as no surprise. It has been a desperately dry winter and spring and the region’s reservoirs are at worryingly low levels.

Inevitably there will be those who grumble that their “right” to waste water is being impinged upon, but water restrictions are a modest impost considering what is at stake.

- Ross Tyson, deputy editor