Here’s a fact worth pondering: Farming accounts for 70 percent of all the water that’s used for any purpose, worldwide. And demand for it is growing, along with the planet’s population and our increasing appetite for meat. That’s according to the UN’s Food and Agriculture Organization (FAO), which recently published this poster and others in a striking series on the vital role of water in growing our food.

But what if that water runs out, leaving fields wilted and stomachs empty? In some places — think of California, or China’s Yellow River basin — there’s genuine scarcity of water for agriculture. Yet according to a collection of studies just published in the journal Water International, that’s an exception to the rule.

Researchers examined ten of the world’s most important river basins, including the Nile, the Mekong, the Volta and the Indus-Ganges, and concluded that in most of them, there’s plenty of water for everyone.

The catch? It has to be used efficiently and shared fairly.

In sub-Saharan Africa, where agricultural productivity is lowest and food shortages are most common, “huge volumes of rainwater are lost or never used,” says Alain Vidal, director of the Challenge Program on Water and Food, which commissioned the studies.

Small reservoirs could help. They catch rainfall and store it until it’s needed. Just as important: All farmers need access to that stored water, not just the wealthy and well-connected.

The “Challenge Program” that sponsored these studies is the brainchild of a far-flung network of institutions called the Consultative Group on International Agricultural Research. It’s dedicated to improving crops and farming practices in the world’s poorest countries.

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