Water scarcity is certainly an issue for growing food in some areas, but a new report, published in Water International says that the world's major rivers basins will have enough water to provide enough food for the growing human population over coming decades. In fact, if (and only if) efficiently and equitably managed, there will be enough water to double or triple food production.
Alain Vidal of the Challenge Program on Water and Food:
Water scarcity is not affecting our ability to grow enough food today. Yes, there is scarcity in certain areas, but our findings show that the problem overall is a failure to make efficient and fair use of the water available in these river basis. This is ultimately a political challenge, not a resource concern.
Huge volumes of rainwater are lost or never used, particularly in the rain-fed regions of sub-Saharan Africa. With modest improvements we can generate two to three times more food than we are producing today.