This collection of photo stories celebrates the way groundwater development has benefited many people.

Groundwater is fundamental to everyday life: spring water, wells and boreholes have provided safe drinking water and reliable water supplies for irrigation and industry for millennia. Today, half the world population is estimated to use groundwater for drinking and a third of the world irrigation comes from groundwater. However, the hidden nature of groundwater often means that its important role, both historically and in the present, is overlooked.

By showcasing examples of groundwater use from around the world, we hope to encourage efforts to develop and manage groundwater sustainably and to protect the supplies of the most vulnerable. These photographs are the finalists from a competition run by the and BGS for the in December 2022.

Jatrabari, Bangladesh

Téhini, Côte d’Ivoire

Mompiano, Italy

Kachchh, India

Nyiragiseke, Rwanda

 Nigeria

Mangochi, Malawi

Alxa Province, China

Malta

Madagascar

Zambia

Madagascar

Orvieto, Italy

Segou region, Mali

More information

The in New York on 22-24 March, is billed as the most important water event in a generation. The conference will review progress halfway through the International Decade for Action on Water for Sustainable Development and encourage new commitments, pledges and actions by governments and all stakeholders towards achieving : access to water and sanitation for all.  Access to water is also needed to achieve many other Sustainable Development Goals, but progress is alarmingly off track.  It is estimated that a sources, with water sources becoming .

Developing and protecting groundwater is fundamental to achieving water related targets, but groundwater is out of sight and therefore .  Nearly all unfrozen freshwater on the earth is groundwater (>97%), locked away in the rocks beneath our feet. Excess rainfall not used by plants, or flows into rivers, infiltrates through the soil to the rocks beneath, where it flows through small pore spaces between grains and crystals, or through cracks and fractures, to reappear in rivers, springs or wetlands – years, centuries or even millennia later.

Nearly half the world population relies on groundwater for drinking, usually accessed from boreholes or wells – and much more is pumped out to help with industry and irrigation.  But groundwater use is not even across the globe and different strategies are required to both unlock its potential and protect it from overuse and pollution.

The story in Africa is largely one of great potential

Many people in countries south of the Sahara lack access to even basic water services. Developing groundwater offers the most realistic way of meeting that need, particularly in dispersed rural communities.  In the same way, there is considerable potential for small scale irrigation to help with food security and build resilience against drought.  What is needed is a step change in investment in finding groundwater, developing appropriate water supplies, and managing both the resource and individual water services.

Here at the 51ÁÔÆæ we have been working with partners such as WaterAid and UNICEF across Africa to try and and address and .Ìý Too often new water supplies break down or don’t function as they could due to a lack of emphasis on regular maintenance, or .

The story across South Asia is very different

Groundwater watered the green revolution in India, Pakistan and Bangladesh with tens of millions of boreholes now accounting for about half of the world groundwater abstraction.  Such is the scale of pumping that in India it is estimated to contribute .  This pumping enables 2 – 3 crops to be grown a year underpinning the region high agricultural output.  However, pumping is largely unregulated and abstraction is much higher than safe environmental limits.  This has led to rapidly falling water levels in some regions, including beneath several major cities, , and in some areas the use of naturally arsenic-rich water for drinking, with devastating consequences for health.

The pressing need in many parts of South Asia is to work out how best to sustainably manage the remaining groundwater and forecast how resources will respond to future abstraction and climate change. BGS is working with partners across South Asia to accurately ; unravel the complex interactions between ; ; and assess the i.

Groundwater is a wonderful resource – naturally climate resilient, of general good quality and widely distributed throughout most countries.  However, it needs to be managed and protected to ensure its benefits are continued to be enjoyed equitably, and for generations to come.  As the leaders, donors and politicians meet in New York to discuss accelerating both access to water and protection of water resources we hope that groundwater will be highly visible.  Measures discussed to protect the overexploitation of groundwater in parts of the world should not stop the investment required to develop new reliable groundwater supplies in Africa, where there is so much potential to use groundwater for good.

About the author

As turns the spotlight to groundwater, we take a look at the work being carried out by our international groundwater team, helping to inspire action towards safe water for billions of people around the world. 

Out of sight and under our feet, in gaps within soil, sand and rock, groundwater is invisible. But its impact is everywhere, keeping rivers flowing in summer and providing safe water for millions. In the driest parts of the world, it may be the only water people have access to. Almost all (more than 97 per cent) of the unfrozen, fresh water in the world is groundwater and nearly half the world population relies on groundwater for drinking water.

Climate change, increasing droughts and irregular rainfall continue to pile pressure on water supplies for people in many communities. Groundwater is nature water reservoir and has great potential to help people adapt to climate change but, like any natural resource, it needs to be carefully managed.

In some places, agricultural and economic needs and human activities lead to the overuse and pollution of groundwater. In other areas, we simply do not know how much groundwater is available, let alone how sustainable these supplies might be in future. We need to work together to sustainably manage this precious resource.

World Water Day is held each year on 22 March. Organised by the United Nations (UN), the event raises awareness of the two billion people currently living without safe access to water, and aims to promote action towards the UN’s Sustainable Development Goal (SDG) 6: . This year, the theme is groundwater.

We have 50 groundwater scientists working on projects in the UK and 20 countries worldwide, mostly in Africa and Asia. We work with partners to understand how groundwater can be developed and managed to sustainably increase water security, reduce environmental damage and help meet the SDGs.

For example, BGS international groundwater team has been developing quantitative groundwater maps for Africa with our partners for the last 10 years, first developing and the type of yield that might be achieved from drilling in different places. More recently, we published a map to show the and a dataset on the of that groundwater and how it is linked to rainfall and climate change.

In the UK, groundwater forms an important component of water supply, providing over 75 per cent of public water supply in the south-east and approximately a third overall in England and Wales. BGS continues to support the work of the environment regulators, the water supply industry and other Government and private organisations in managing groundwater. For example, we are currently working with the Environment Agency in England to review the recent science on climate change and its impact on groundwater and the environment, and we are developing infrastructure across the UK to monitor the impacts of the increasing risk of groundwater-related floods and droughts.

For World Water Day 2022, BGS scientists Prof Alan MacDonald and Dr Daniel Lapworth have contributed to the official UN , a flagship report released by UN-Water, which this year aims to provide an authoritative, comprehensive assessment of the world groundwater resources.

51ÁÔÆæ has collaborated with WaterAid to produce a new report , which examines more closely and at a national scale whether there is potentially enough groundwater in future to sustainably supply populations in Africa with a certain amount of water (130 litres) per day.

Experts from our international groundwater group are supporting the Foreign, Commonwealth and Development Office (FCDO) in briefing key diplomats about the importance of protecting and managing groundwater resources.

Further contributions by our BGS international groundwater team include:

• A new Economic Community of West African States groundwater map, to be launched at the World Water Forum in Dakar, 22 – 27 March 2022
• The White Paper on Groundwater for Africa Socio-economic Transformation from the African Ministers’ Council on Water, to be released and discussed at World Water Forum in Dakar
• A BGS exhibition on groundwater at the Scottish Government World Water Day event in Dynamic Earth, Edinburgh
• The publication of a new book, , featuring BGS authors, will follow World Water Day, set to be released on 31 March 2022

Today is UN World Water Day, an annual celebration of the importance of freshwater. Groundwater accounts for over 97 per cent of fresh water on Earth that is available for use (e.g. not frozen in glaciers and ice caps).

This year theme for World Water Day is ‘Valuing Water’. Here, hydrogeologist Jade Ward gives and overview of what groundwater is and highlights three areas of innovation and research in hydrogeology that demonstrate the value of groundwater. Groundwater resources are helping to address worldwide issues such as the global water crisis, waterborne disease and climate change adaptation.

What is groundwater?

Groundwater is often considered a ‘hidden asset’ because it is out of sight, in the ground beneath our feet. Found within rocks, in fractures and in tiny spaces (pores) between rock particles, groundwater accounts for 30 per cent of all fresh water on Earth and over 97 per cent of fresh water that is available for us to use. The vast majority of water on Earth is found in the oceans and most fresh water is locked up in glaciers, ice caps and snow.

Groundwater and the global water crisis

The world is currently facing a global water crisis, with the combined pressures of climate change and population growth leading to drought and water shortages on a more widespread, frequent and severe scale than previously experienced.

Groundwater is naturally stored in the ground, in rocks called aquifers. This natural storage provides a buffer to climate change impacts. For example, in times of drought river flow reduces and is naturally sustained by groundwater baseflow. In regions with highly seasonal rainfall, rivers often run dry, but groundwater is often still be available to use. With climate change expected to increase the magnitude and frequency of extreme weather events, it is predicted that more regions of the world (including the UK) will have to cope with more extremes in climate variability. Groundwater will be a key resource in adapting to these changes. Groundwater research is helping scientists to understand more about droughts, and the role of groundwater to build resilience of water supplies. 

Groundwater and combatting waterborne disease

At least two billion people worldwide use a drinking water source that is contaminated with faeces (WHO, 2019). Groundwater quality is typically less likely to be contaminated with microbial pathogens than surface water, because groundwater is naturally filtered as it moves through the aquifer. This generally reduces turbidity (the cloudiness of the water) and pathogen transport. This is especially important in areas where there is no treatment available for drinking water, for example in low- and middle-income countries.

However, not all groundwater sources are free from microbial contamination. If the borehole is near to a contamination source or is not well maintained (or both!) then contamination can occur. Monitoring groundwater quality is important to measure progress towards UN Sustainable Development Goal 6: safe access to water and sanitation for all by 2030. Jade’s PhD research focused on investigating new methods of detecting microbial contamination, to see if we can improve water quality monitoring. Recent developments are focusing on improving the speed and accuracy of results.

Even if groundwater quality is good, groundwater sources still need to be managed sustainably to continue to provide water, including consideration of potential climate change impacts, and the best way to maintain water infrastructure.

Groundwater for low-carbon heating

The UK is the first G7 country to sign up to a legally binding net zero carbon target. This is a significant step towards mitigating the impacts of climate change. Groundwater heat pumps could offer a low-carbon alternative to traditional carbon-intensive heating systems, which could help the UK to reduce carbon emissions. Groundwater is used to heat a liquid refrigerant to become a gas, which links into a building heating system. Mine water geothermal energy is a current research topic in the UK. It is important to understand the sustainability of such systems, potential issues that might arise and how to deal with them, and how to ensure environmental protection. Economic and regulatory aspects also need to be considered if this is to become an affordable technology.

Groundwater is already a valuable resource and it is going to become more important in tackling climate change and ensuring water security around the world. It really important that we understand where our water comes from, the benefits of using groundwater sustainably, and how to protect it. The theme for UN World Water Day 2022 is ‘Groundwater: Making the Invisible Visible’, which will raise awareness on a global scale. Look out for more about this in future blogs.

Find out about all the going on at BGS and follow the groundwater team on X .

About the author

Jade Ward was a hydrogeologist at BGS and worked on a range of groundwater-related projects.

Find Jade online:
|