Water is our most fundamental natural resource. It is also the most renewable. The stuff we drink today is the same water the first fish swam in, the dinosaurs drank, and which froze across much of the globe during the ice ages...
It all begins with a few thin clouds in the clear blue sky over the Indian Ocean. They are barely noticeable at first as the wind picks up and water vapour condenses to form tiny cloud droplets, and the droplets bump into each other and coalesce. The clouds grow and darken. Thunder claps and the first giant raindrops fall on the southern tip of India. The monsoon, the planet’s greatest annual weather system, has begun its magic. The clouds sweep north across the subcontinent, enveloping the land in curtains of rain and bringing relief to a parched and overheated soil. In about a hundred hours spread across a hundred days, millions of villages across India receive virtually their only rain of the year.
The rain swells rivers, floods low-lying land, fills reservoirs and irrigation canals, turns deserts green and brings crops to life. The water percolates through soils to fill the pores in rocks beneath. In the Himalayan mountains, the rains combine with melting waters from ancient glaciers to feed great rivers like the Ganges, Brahmaputra and Indus. As the first rains come each June, Indians rush into the streets and party. They put on festivals for their Hindu water gods. They head for their fields to plant crops in the damp soil. They clear debris from ancient channels that divert the precious rains into ponds and lakes – anywhere that they can store the life-giving waters.
The rituals of the monsoon are repeated all across Asia. The first rains are a time for celebration and thanksgiving. In Southeast Asia, fishermen and farmers wait for the first spring flows to revive the Mekong. In China, the Yangtze River brings waters that will feed more than a billion people. In the Americas, under different weather systems, farmers watch the skies for the first sign of storms forming in the Caribbean. In Africa there is special nervousness. If the rains fail, it can mean famine and starvation. But everywhere people instinctively know the truth of Benjamin Franklin’s famous saying: “When the well’s dry, we know the worth of water.”
Water is our most fundamental natural resource. We cannot survive without it. But it is also our most renewable resource. Those clouds forming over the Indian Ocean are just the latest step in a never-ending water cycle. The stuff we drink today is the same water that the first fish swam in, which the dinosaurs drank and which froze across much of the globe during the ice ages. Our planet probably has no more and no less than it ever has. Each day some 200 trillion gallons evaporate from the oceans or the land to keep the water cycle in motion. On average it stays in the air for ten days before falling again as rain.
But from the High Andes to the plains of India, from southern Europe to northern China, rain is becoming increasingly unpredictable. Global warming is pumping more energy into weather systems and making them more intense, and that can bring both floods and droughts. In places, rivers are running dry as rains fail and we take ever more water to irrigate our crops. Conflicts over remaining supplies loom. In other places, warmer air is making storm clouds more intense and generating super-storms and hurricanes. Hard rains are creating havoc.
And yet, in some places at some times, we are running out of water. Underground reserves that farmers could once reach by dropping a bucket into a well only a few feet deep are now so empty that a borehole drilled half a mile down finds no water. The great rivers we heard about in our geography lessons in school – strong blue lines on our atlas maps – are running dry. The Nile in Egypt, the Ganges in India and Bangladesh, the Indus in Pakistan, the Yellow River in China and the Colorado in the US are among them. It is not that nature’s water cycle is faltering. Far from it. But our demands on it are increasing so much that, in some places at some times, we are exhausting it.
Twentieth century engineering, like dams and irrigation canals, are failing. Instead many communities are going back to traditional ways of managing water. They are harvesting the rains and diverting floodwaters into wells to save it for the next drought.
Hard Rain 2nd edition, 2007