Not only is today World Water Day but March is Rotary's Water and Sanitation Month, emphasizing the importance of clean water and sanitation systems. For World Water Day, the emphasis this year is on groundwater, "making the invisible visible." Almost all the liquid freshwater in the world is groundwater. While out of sight, under our feet, groundwater is a hidden treasure that enriches our lives. As climate change gets worse, groundwater will become more and more critical. We need to work together to sustainably manage this precious resource. Groundwater may be out of sight, but it must not be out of mind. For information on World Water Day go to https://www.worldwaterday.org/.