And as the water dries up, our population continues to grow massively.

By 2025 two thirds of the world's population - a staggering five billion people - will face severe water shortages.

Chemical Engineers - the scientific shock troops

Experts are desperately warning that the next big war will be fought over water.

Potential flashpoints already being identified by the UN Development Programme are around the rivers Cuito, Mekong, Nile, Niger, Volta and Zambesi.

That's the bad news.

The good news is that it's not too late.

All over the world experts are seeking a range of ingenious solutions that will both make the world's water cleaner and make sure it's available to ever more people.

Those experts are Chemical and Biochemical Engineers - the shock troops of the battle for the planet's very survival.