Water covers most of the planet, yet the fresh water that farms, cities and ecosystems depend on is a startlingly thin slice of the total — and it's unevenly spread, easily polluted and, in many places, being used faster than it's replaced. This episode looks at where fresh water actually is, why so little of it is usable, and the pressures building on this most essential of resources, with a particular eye on Australia's Murray–Darling Basin.

You'll come away understanding how little of Earth's water is fresh and accessible, the role of groundwater and aquifers, what “water stress” really means, and why managing shared river systems is one of the hardest balancing acts in resource policy.

Talking Science is sponsored by Kinsoft. Visit www.kinsoft.com.au ...