【明報專訊】Around 70 percent of Planet Earth's surface is covered by water. According to the United Nations, fresh water accounts for 2.5 percent of all water resources, but only 1 percent is suitable for human use. Global warming is affecting normal rainfall. This, coupled with the depletion of underground water, ecological destruction, the use of water in agricultural, economic activities and pollution, has worsened the scarcity of water resources. A 2017 report by the World Health Organization (WHO) and UNICEF said that 2.1 billion people around the world did not have access to safe water.