United Nations, Mar 23 (IANS): UN Secretary-General Antonio Guterres has called for the sustainable use of groundwater for future generations.

"On this World Water Day, let us commit to intensifying collaboration among sectors and across borders so we can sustainably balance the needs of people and nature and harness groundwater for current and future generations," the UN chief said in his message for the international day, which is observed annually on March 22 and highlights the importance of fresh water.

The secretary-general underscored that humanity's demand for water is growing and pressure on water resources is increasing due to overuse, pollution and climate change, Xinhua news agency reported.

"Droughts and heatwaves are becoming more intense and more frequent. Sea-level rise is driving salt-water intrusion into coastal aquifers. Groundwater aquifers are being depleted," he said.

The top UN official said that water can be a source of conflict but also of cooperation. "It is essential that we work together to provide better stewardship of all water sources, including the world's supply of groundwater."

On the situation of groundwater, the secretary-general said that it is "out of sight, but we cannot afford for it to be out of mind."

"Stored in rocks and soil, groundwater is our biggest source of liquid freshwater," the secretary-general said, adding that "it sustains drinking water supplies, sanitation systems, farming, industry and ecosystems. Yet, some 20 per cent of the world's aquifers are being overexploited."

"In many places, we simply do not know how much of this precious resource might exist. We need to improve our exploration, monitoring and analysis of groundwater resources to protect and better manage them and help achieve the Sustainable Development Goals," the UN chief noted.