Worsening water shortages will leave Africans poorer, hungrier and even more dependent on aid unless governments do more to help conserve one of the region's most precious resources, scientists said Sunday.
Researchers gave their warning at the opening of a five-day conference in Kenya to find ways to help Africa better manage its rivers and rainfall to ward off famine and flood.
As Africa's population rises, demand for household water is projected to grow faster than anywhere else on the planet, leaving up to 523 million people without access to clean water by 2025 unless governments invest in better infrastructure.
Farmers already struggling to raise crops in arid countries from Ethiopia to Chad and Mauritania are likely to face increasing competition for water, meaning they will have less to irrigate their crops, which would reduce already meager yields.
Countries with more plentiful rainfall such as Congo, Zambia and South Africa must do more to harness the resource and improve management if they are to avoid floods like those that struck Kenya and Mozambique in recent years, the experts said.
"The crisis has to be addressed comprehensively at all levels, from the way farmers use water to international policy decisions that affect reforms and investments in water management and infrastructure," said Frank Rijsberman, chairman of the Challenge Program on Water and Food consortium, a group of researchers looking at water scarcity.
The experts said Africa could face a 23% shortfall in crop yields due to insufficient water supplies, while cereal imports will have to more than triple to 35 million tons in the next 23 years to meet demand, increasing reliance on aid.
Water shortages are predicted to affect the livelihoods of one-third of the world's population by 2025, perhaps resulting in losses in food production equivalent to the entire grain crops of the United States and India combined.
The meeting, organized by the Consultative Group on International Agricultural Research, will also discuss the impact on water use of rules set by the World Trade Organization, which governs global trade.
"Agricultural subsidies in North America and Europe determine where food is grown," Rijsberman said.
"And policy decisions taken in the World Trade Organization are possibly the single most dominant factor shaping the global demand for food and consequently the amount of water required to grow that food."