Groundwater accounts for 99% of all liquid fresh water on Earth. However, this natural resource is often poorly known and therefore undervalued, poorly managed and polluted. This year’s World Water Day, March 22, highlights the vast potential of groundwater and the need to manage it sustainably by “making the invisible visible”.

“Groundwater can be out of sight, but it shouldn’t be out of sight,” UN-Water stresses.

Groundwater currently provides half of the volume of water withdrawn for domestic purposes by the world’s population, including drinking water for many people in rural areas, and about 25% of all water used for the irrigation.

Globally, water consumption is expected to increase by approximately 1% per year over the next 30 years.

More than 2 billion people live in water-stressed countries and 3.6 billion people face insufficient access to water at least one month a year.

According to World Water Development Reportwhich was released at the World Water Forum in Dakar, Senegal.

The report calls on states to commit to developing adequate and effective groundwater management and governance policies to address current and future water crises around the world.

“Improving the way we use and manage groundwater is an urgent priority if we are to achieve the Sustainable Development Goals (SDGs) by 2030. Policy makers must begin to take full account of the critical ways in which groundwater can contribute to ensuring the resilience of human life and activities in a future where the climate becomes increasingly unpredictable”, adds Gilbert F. Houngbo, President of UN-Water, President of the International Fund for Agricultural Development (IFAD) and leader of the Water and Climate Coalition led by OMM.

Mr. Houngbo and other leaders of the Water and Climate Coalition are attending the World Water Forum to highlight the need for integrated action on water and climate. They recently issued a call to action, including a commitment to establish a global water information system to close the gaps in reliable data and actionable information.

“We need data to understand how climate change is affecting our water systems; to understand where, how much and what quality water is and will be available. We need information to know where and how our actions can best support our access to the precious resource and protect us from water-related risks and disasters.Data is also essential for smart decision-making.Yet there are major gaps; data is scattered, inconsistent and incomplete,” said the [Call for Action](https://public.wmo.int/en/media/press-release/protect-our-people-and-future-generations-water-and-climate-leaders-call-urgent#:~:text=Geneva% 208 %20March%202022%20(WMO,at%20the%20availability%20of%20of%20and%20of).

This is especially true for groundwater.

Only 0.5% of the water on Earth is usable and available as fresh water. But over the past 20 years, the Earth’s water storage – all water above and below ground, including soil moisture, snow and ice – has dropped to a rate higher than the total human water consumption per year. This has huge ramifications for future water security, given population growth and environmental degradation, according to the WMO’s State of Climate Services for the World report. water released last year.

Groundwater quality is generally good, meaning it can be used safely and cheaply, without requiring advanced levels of treatment. Groundwater is often the most cost effective way to provide a secure water supply to rural villages.

The World Water Development Report has shown that some regions, such as sub-Saharan Africa and the Middle East for example, hold substantial amounts of non-renewable groundwater that can be extracted in order to maintain water security. However, consideration for future generations and for the economic, financial and environmental aspects of storage depletion should not be overlooked.

Despite the challenges ahead, there is currently no functioning global system capable of assessing the current state of surface and groundwater hydrological systems, or predicting how they will change in the weeks and months to come.

WMO is therefore involved in a number of initiatives to address this situation, including the new WMO Global Hydrological Status and Outlook System (HydroSOS).

When operational, HydroSOS will regularly report:

• the current global hydrological state, including groundwater, river flow and soil moisture;
• an assessment of where the current condition is significantly different from ‘normal’, for example indicating potential drought and flood situations;
• and an assessment of whether it is likely to improve or worsen over the coming weeks and months.

Resources for World Water Day are available here