Press Trust of India: The United Nations warned that two-thirds of the world’s population will face a lack of water in less than 20 years if current trends in climate change, population growth, rural to urban migration and consumption continue. Speaking at a high-level symposium on water security here yesterday, UN Dy Secretary-General Asha-Rose Migiro stressed that “if present trends continue, 1.8 billion people will be living in countries or regions with water scarcity by 2025, and two-thirds of the …