Groundwater is in our veins

UN World Water Day 2022 on Groundwater: Making the invisible visible

Freshwater availability is under pressure globally, quantitatively by intensifying droughts and demand and qualitatively by salinization and contamination. The use of 96 million floating shade balls to prevent evaporation from a water reservoir serving Los Angeles and plans to tow icebergs from Antarctica to South Africa illustrates the global water crisis. With groundwater already providing half of all drinking water and a quarter of irrigation use, the global water crisis is also very much a global groundwater crisis, further aggravated by global warming.

Overall, fresh groundwater volumes are shrinking faster than they are being replenished. Recent estimates indicate that up to 20% of global groundwater wells are in danger of drying up. You almost start to think that there’s not so much fresh groundwater left. Volumetrically, however, groundwater still accounts for 99% of all liquid freshwater on Earth! While groundwater is also essential for maintaining river base flows and groundwater-dependent ecosystems, groundwater is hidden beneath our feet, unlike rivers, swamps and lakes. It flows slowly through sand and other porous layers, called aquifers, formed and buried during geological times.

Because of the global importance of groundwater and the fact that it is easily overlooked, UN-Water chose “Groundwater: making the invisible visible” as the theme for World Water Day 2022. Although raising awareness of groundwater’s existence and importance with the general public and policymakers is challenging due to groundwater’s hidden nature, the potential gains are plentiful. As indicated by the accompanying UN World Water Development Report, significant parts of the world, such as Saharan Africa and the Middle East, hold substantial untapped quantities of non-renewable groundwater supplies that can be extracted in order to maintain water security. However, the fossil nature of these geologically trapped groundwater reserves also holds the risk of developing an unsustainable water demand. Therefore, there’s generally not a lack of renewable groundwater, groundwater that is being recharged by present-day precipitation, and its quality is usually good.

Groundwater can be used safely and affordably, without requiring advanced levels of treatment, to provide a secure supply of water to rural villages in many parts of the world. However, when unlocking the potential of groundwater, educated groundwater management is crucial for the availability of fresh groundwater to be sustainable. One has to learn from the many mistakes made in the past. Preventing wells from running dry or land subsidence by not abstracting more groundwater than is natural recharged and avoiding contamination groundwater, e.g., latrines, landfills, agriculture, and industry. This requires public and policy awareness of groundwater and what it means to us. Think about it the next time you enjoy your groundwater-fed spring (formerly known as “the shower”) or drinkable groundwater (formerly known as “drinking water”). Please help us communicate this message.