UN World Water Development Report - 2022 edition

The UN World Water Development Report is UN-Water's flagship report on water and sanitation issues, focusing on a different theme each year. The report is published by UNESCO, on behalf of UN-Water and its production is coordinated by the UNESCO World Water Assessment Programme. The report gives insight on main trends concerning the state, use and management of freshwater and sanitation

The 2022 edition of UNWWDR was released on World Water Day on March 22, 2022. Titled Groundwater: Making the invisible visible, it describes the challenges and opportunities associated with the development, management and governance of groundwater across the world. The report addresses groundwater-related issues from the perspective of the three main water use sectors – agriculture, human settlements and industry – as well as its interactions with ecosystems and its relation to climate change. It highlights different regional perspectives

Key messages:

• Globally, water use is expected to grow by roughly 1% per year over the next 30 years. 
• This growth is primarily concentrated in emerging economies and middle- and lower-income countries. It is driven by increasing demands from the agriculture (food), industry and energy sectors as well as by municipal and domestic uses. 
• This growth is mainly as a function of industrial development and improving water and sanitation service coverage, in combination with population growth, economic development and shifting diets and consumption patterns. 
• Combined with surface water scarcity, which is increasing due to climate change, the water crises facing humanity is real, but it is avoidable. 
• While our reliance on groundwater will also definitely increase, its full potential remains largely untapped. 
• Groundwater accounts for 99% of all liquid freshwater on Earth.
• Massive volumes of fresh groundwater are present below ground and distributed over the entire globe. However, their abundance and the conditions for their withdrawal can be very different from place to place.
• At the global level, 25% of the total freshwater we use comes from groundwater. 
• Groundwater provides 50% of the volume of freshwater withdrawn for domestic use worldwide, including the drinking water for the vast majority of the rural population.
• It also accounts for around 25% of all water withdrawn for irrigation, serving 38% of the world’s irrigated land.
• Overall, the agricultural sector accounts for 69% of all groundwater abstractions, followed by 22% for domestic uses, and 9% for industrial purposes.
• Groundwater withdrawal boomed during the 20th century, doubling over the past 70 years.
• Groundwater withdrawal for human uses is very important, but it corresponds to only one category of the services offered by groundwater systems. 
• In addition to the provisional services, groundwater systems provide regulatory and supporting services related to water availability, quality, and groundwater-dependent ecosystems. For example, they can play a role in water purification, provided that pollution levels do not exceed their natural decontamination capacity.
• Groundwater systems also provide cultural services including leisure activities. Traditional, religious or spiritual values are sometimes associated with particular wells or natural springs. 
• Groundwater storage depletion, accompanied by declining groundwater levels, occurs when groundwater discharge (i.e. the sum of groundwater withdrawal and ‘unforced’ or natural discharge) exceeds recharge. 
• The rate of global aggregated groundwater depletion is considerable: for the beginning of the present century, the estimates are mostly between 100 and 200 cu.km/year, accounting for roughly 15 to 25% of total groundwater withdrawals. 
• The quality of groundwater is generally good, which means it can be used safely and affordably, without requiring advanced levels of treatment. 
• Groundwater pollution reduces the suitability of abstracted groundwater for drinking purposes and other human uses. And, like groundwater depletion, it can also negatively impact groundwater-dependent ecosystems.
• The Asia-Pacific region is the largest groundwater abstractor in the world, containing seven out of the ten countries that extract most groundwater (Bangladesh, China, India, Indonesia, Iran, Pakistan and Turkey). These countries alone account for roughly 60% of the world’s total groundwater withdrawal. 
• While groundwater is abundant across most of the region, its depletion has led to concerns over the sustainability of groundwater usage in different areas across Central Asia, China, South Asia and certain urban centres in Southeast Asia. Climate change is further exacerbating pressure on groundwater resources, particularly in areas with semi-arid to arid climates and on Pacific Small Island Developing States, where groundwater, often the only reliable source of freshwater, is threatened by rising sea levels.
• Groundwater contamination from both anthropogenic and geogenic processes is an additional concern.

The take away messages from the report are:

• The abundance of groundwater resources will prove essential in meeting increasing global demands for water, especially during periods of severe water stress.
• Improved groundwater management and governance are needed in order to avoid overexploitation and contamination.
• Groundwater systems support valuable ecosystem services and can play a critical role in climate change adaptation and mitigation.
• The development of under-exploited groundwater resources in places like Sub-Saharan Africa offers opportunities for food security and economic growth.
• Given its common-pool nature, all data and information about aquifer systems should be made available to groundwater managers.
• Unlocking the full potential of groundwater for ourselves and for future generations will require strong and concerted efforts to manage and use it sustainably.