He probably didn't imagine that he was describing a situation that within two centuries would become daily reality for more than a billion people. The report, authored by 200 leading scientists from 50 countries, identified a shortage of clean water as one of the most urgent problems facing humanity. Each year, water-related diseases kill 15 million children under the age of 5. If action is not taken, by the year 2025, two-thirds of the world's population will live in areas with unstable water supplies. The global water problem is the result of several factors, most prominently the growing population.
More people means more demand for water for domestic, agricultural, and industrial use.
The growing population must eat. Production of a ton of grain requires roughly 1,000 tons of water. Uneven distribution is also a factor. For example, Africa's Niger Delta receives significant quantities of rain, while the nearby Sahara Desert gets very little. According to GEO-2000, there are 50 African rivers that provide water to two or more countries.