In many river basins and aquifers, farms, industry and cities withdraw more fresh water than nature can renew, leaving less for people, food production and ecosystems in dry years and in the future.
Updated October 14, 2026. Written from the sources listed below, not independently peer-reviewed.
Roughly how many people face severe water scarcity for at least one month every year?
17.6%
Global level of water stress
Share of renewable fresh water withdrawn worldwide after environmental needs, almost unchanged since 2015 (17.8%). An FAO estimate built from national data.
Data year 2023. Source: United Nations Statistics Division, 2026
About 10%
People in countries with high or critical water stress
Of the world population, living in countries that withdraw at least 75% of their available fresh water. Based on national averages, so local and seasonal shortages are not included.
Data year 2023. Source: United Nations Statistics Division, Department of Economic and Social Affairs, 2026
About 70%
Major aquifers in long-term decline
Groundwater supplies about half of the world's domestic water and over 40% of irrigation water. Figure as reported by the UN University in January 2026.
Data year 2026. Source: United Nations University Institute for Water, Environment and Health, 2026
Unit: % of available fresh water withdrawn
FAO estimates for SDG indicator 6.4.2 from the UN SDG Global Database: total freshwater withdrawals as a share of renewable resources after environmental flow requirements. Five of the annual values are shown; years in between are not plotted. The flat world line masks rising stress in Northern Africa and Western Asia and does not capture seasonal or local shortages.
SDG target 6.4 aims by 2030 to make withdrawals sustainable and substantially reduce the number of people suffering from water scarcity. The 2026 UN SDG report finds the global level of water stress steady at about 18% since 2015, with about 10% of people living in countries under high or critical stress and countries in Northern Africa and Western Asia and in Central and Southern Asia above 75%. Water-use efficiency rose 24% between 2015 and 2023, but mostly because economies grew, while total withdrawals stayed almost flat.
Water stress in Northern Africa and Western Asia rose from about 73% to about 78% of available resources between 2015 and 2023, while in Central and Southern Asia it fell from about 72% to 68%. Both regions remain far above the world average of about 18%.
Source: United Nations Statistics Division, 2026In 2022, 13% of the world's countries, home to 10% of the global population, had high or critical water stress. Between 2015 and 2022, stress rose by more than 15% in Northern Africa and by 9% in Western Asia.
Source: United Nations / UN-Water, 2026A study of about 170,000 wells in more than 40 countries found groundwater levels falling by more than 10 cm a year in 36% of the monitored aquifer systems and by more than 50 cm a year in 12%. The steepest declines were under farmland in dry climates.
Source: University College London, 2024The UN University points to the Middle East and North Africa, where high stress meets climate risks and energy-intensive desalination, and to parts of South Asia, where groundwater-fed farming and urban growth have caused chronic falls in water tables and local land subsidence.
Source: United Nations University Institute for Water, Environment and Health, 2026Each country is shaded by its latest available value, so you can see where the gap is widest. Hover or tap a country, search for one, or open the full table.
Loading country values…
Total freshwater withdrawals by agriculture, industry and services divided by renewable freshwater resources after environmental flow requirements (SDG 6.4.2). Latest year available per country, 2022 for almost all (years can differ). FAO counts 75–100% as high and above 100% as critical stress; values above 100% mean more is withdrawn than renewably available. National annual averages hide seasonal and local shortages, so a low value does not rule out scarcity in parts of a country.
Source: FAO AQUASTAT (SDG indicator 6.4.2), via World Bank Open Data. Latest year available per country; years differ.
Values load from World Bank Open Data. Simplified Natural Earth borders; they imply no position on disputed territories.
Instead of one “percent solved” score, DO GOOD rates three separate dimensions. A problem can have mature solutions that still reach too few people. These ratings are an editorial reading of the sources on this page, not a measured index.
Has the situation improved in the real world?
LowThe global level of water stress has hardly moved since 2015 and rose in Northern Africa and Western Asia, from about 73% to 78% by 2023. Groundwater keeps falling in many of the most important aquifers.
How mature and validated are the available solutions?
ModerateAllocation rules, efficient irrigation, water pricing, reuse and desalination are well known, and Singapore cut its level of water stress by 61% between 2015 and 2022 by combining them. Several of these options need large investment, and desalination is energy-intensive.
How widely are effective solutions actually used?
LowIntegrated water resources management averaged 57% implementation worldwide in 2023, 73 countries are classed as left behind, and 54% of countries still produce less than US$20 of value per cubic metre of water used.
FAO's country estimates follow an agreed method, but data on withdrawals and environmental flows are limited in many countries, self-supplied industrial water is often missing, and national averages hide local and seasonal shortages.
Water-use efficiency is improving and a few highly stressed countries have reduced their stress, but the global level is flat, stress is rising in Northern Africa and Western Asia, and groundwater declines have accelerated in 30% of the world's regional aquifers over the past four decades.
Water scarcity is about quantity rather than quality: whether there is enough fresh water, over the year and from year to year, to meet what households, farms, industry and ecosystems need. It is a different problem from access to safe drinking water, although the two often meet. Worldwide, about 18% of renewable fresh water is withdrawn once environmental needs are set aside, a level that has barely changed since 2015. The average hides large gaps: in Northern Africa and Western Asia withdrawals reached about 78% of available resources in 2023, and in Central and Southern Asia about 68%, while sub-Saharan Africa withdrew about 10%. Agriculture accounts for 72% of all withdrawals.
Where withdrawals exceed renewal for years, rivers run lower, lakes shrink and groundwater is pumped faster than it refills. The UN University estimates that about 70% of major aquifers show long-term decline and that about half of the world's large lakes have lost water since the early 1990s. Some of the damage cannot be reversed: compacted aquifers lose storage for good, and about 2 billion people live on ground that is sinking. Scarcity raises the cost of droughts, which the same report puts at US$307 billion a year, and puts at risk food production, since more than half of the world's food is grown in regions where total water storage is declining or unstable.
SDG target 6.4 calls for sustainable withdrawals and supply of fresh water and for substantially fewer people suffering from water scarcity by 2030. Its main measure, SDG indicator 6.4.2, is compiled by FAO from national data. It rests on these elements:
Withdrawals against renewable supply
The level of water stress divides the fresh water withdrawn by agriculture, industry and services by the total renewable freshwater resources of a country or region. A value above 100% means more is withdrawn than is renewably available.
Water set aside for nature
Before the ratio is calculated, the water that rivers and wetlands need to keep functioning (environmental flow requirements) is subtracted from the available resources, so the indicator counts nature's needs as a first claim.
Five levels of stress
FAO and UN-Water group countries into no stress (below 25%), low (25–50%), medium (50–75%), high (75–100%) and critical (above 100%). The SDG reports count the people living in countries with high or critical stress.
National annual averages
The indicator gives one figure per country and year. It does not show dry seasons, drought years or stressed basins inside otherwise well-supplied countries, which is why other estimates that look at months and river basins find far more people affected.
What works
Better irrigation, crop choices and water management raise the economic value produced per cubic metre. Global water-use efficiency rose from US$17.4 to US$21.5 per cubic metre between 2015 and 2023, and agricultural efficiency improved by 39%.
Limits
Agriculture still yields about US$0.7 per cubic metre against US$38 in industry, and most of the global gain came from economic growth: total withdrawals stayed at about 4,022 km³ a year.
What works
Integrated water resources management sets rules for who may withdraw how much, coordinated across sectors and at the scale of river basins and aquifers. Nearly 60% of countries had reached at least medium-high implementation in 2023, up from 40% in 2017.
Limits
At the current pace the global target will not be reached until at least 2049, about 70% of countries report too little funding for basin and aquifer management, and limits on withdrawals are politically hard where many livelihoods depend on irrigation.
What works
Treating wastewater for reuse and desalinating seawater add supply that does not depend on rainfall. Singapore reduced its level of water stress by 61% between 2015 and 2022 through diversified supply, including desalination and reuse, combined with water pricing and strong political commitment.
Limits
Both options need large investment and energy; the UN University describes desalination in the Middle East and North Africa as energy-intensive. A wealthy city-state's experience does not transfer easily to large farming regions where most water is used.
What works
A global study of aquifer records found cases of recovery, from Albuquerque in the United States to Bangkok in Thailand, after water conservation policies, transfers between basins or deliberate recharge with surface water and floodwater.
Limits
The study documents far more declines than recoveries, long-term records are sparse in tropical Africa and Latin America, and where an aquifer has already compacted, refilling it does not restore the lost storage.
What works
Treaties and joint bodies for transboundary basins let countries plan withdrawals together and share data. There are 313 transboundary rivers and lakes and 426 transboundary aquifers, and the number of countries reporting on cooperation rose from 107 in 2017 to 129 in 2023.
Limits
Only 43 of 153 countries that share waters have arrangements covering 90% or more of their transboundary basin area, and at least 20 have none. Knowledge of transboundary aquifers lags well behind that of rivers.
Promising, but not proven at scale. The stage shows how far each approach has come; it is not a recommendation.
A new SDG measure compares each river basin's annual minimum flow with a 2000–2019 baseline. It found significant decreases in 402 of 12,572 basins, about five times the baseline rate. It measures flows rather than their causes, so on its own it does not show how much of a decline is due to withdrawals rather than climate.
Directing surface water and floodwater into depleted aquifers has helped groundwater levels recover in some places. The documented cases are local, and how far and where such recharge can offset large-scale pumping is not yet known.
The UN University proposes treating basins where damage can no longer be reversed as bankrupt: stopping further harm, resetting water rights to what the degraded system can supply, and supporting communities whose livelihoods must change. The concept was set out in 2026 in the UN report and a supporting peer-reviewed paper, and is new to water planning.
Satellites, AI and combined models could estimate withdrawals, water storage and land subsidence where meters and wells are missing, and the UN University calls for building such monitoring into global frameworks. Turning such estimates into figures that governments accept and use for allocation is still at an early stage.
Implementation gap
Agriculture accounts for 72% of freshwater withdrawals and produces the least value per cubic metre. Cutting farm water use touches food supply and rural incomes, so allocation reforms are slow and contested.
Implementation gap
In 2023, about 70% of countries reported insufficient funding for most water resources management needs and 85% needed more effective ways of raising revenue. Aid for water has declined in recent years, which the 2026 synthesis report calls a growing threat.
Coordination gap
Water-use efficiency rose 24% between 2015 and 2023, yet total withdrawals barely changed, because the gain came mainly from economic growth. Without caps on withdrawals, efficiency alone does not relieve stressed rivers and aquifers.
Coordination gap
At least 20 countries have no operational arrangements for their shared rivers, lakes or aquifers. In 2023 only 2 of 41 Asian countries and 1 of 22 Latin American countries had arrangements covering 90% or more of their transboundary basin area.
Knowledge gap
Water that industry draws directly from rivers and groundwater is often missing from public statistics, data on withdrawals and environmental flows are limited in many countries, and lakes and groundwater are monitored less than rivers. Only about 60,000 of 2 million water quality records in 2023 came from the lower-income half of countries.
Technology gap
No technical fix can reinflate compacted aquifers, raise sinking deltas or rebuild lost glaciers; the UN University notes that some cities are sinking by 25 cm a year. Plans that aim to return to past conditions can over-promise water that no longer exists.
Unresolved questions, not vetted breakthroughs. Answering any of them would change what is possible.
Environmental flow requirements and safe rates of groundwater use are estimated with simple rules in many places. How much water do specific rivers, wetlands and aquifers actually need to keep functioning?
When irrigation becomes more efficient, under which rules and prices does the saved water stay in rivers and aquifers, and when is it used to irrigate more land?
National annual averages count about 10% of people in highly stressed countries, while monthly, basin-level estimates find about 4 billion facing severe scarcity at times. Which local and seasonal measure best reflects the shortages people experience?
At what point do falling groundwater levels lead to permanent loss of storage and land subsidence, and can this be detected early enough to change course?
Water stress is local. Check what your water utility or river basin authority publishes about local supply, groundwater levels and drought plans, and follow its guidance during dry periods.
Outdoor watering and leaks are among the household uses that are easiest to reduce. Fixing leaks, watering less and choosing plants suited to the local climate lower demand, most usefully in dry seasons when supplies are tightest.
Most fresh water is used to grow food, so food that is thrown away carries wasted water with it. Buying and cooking what you will eat is one of the few household choices connected to agricultural water use.
Allocation rules, tariffs and groundwater permits are set by local and regional authorities, often with public consultation. Responding to these consultations and supporting fair, enforced limits can matter more than individual savings.
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United Nations Statistics Division (data compiled by FAO), published 2026
Official SDG 6.4.2 time series for the world (total and by sector, 2000–2023) and, with other area codes, for SDG regions. Source of the trend points, the 2023 global value of 17.59% and the regional values for Northern Africa and Western Asia (747), Central and Southern Asia (62) and sub-Saharan Africa (202).
United Nations Statistics Division, Department of Economic and Social Affairs, published 2026
Official storylines for SDG 6 indicators. Source of the global water stress level (18% in 2023), the 10% of people in countries with high or critical stress, regions above 75%, sector shares of withdrawals, water-use efficiency 2015–2023 by sector, total withdrawals, IWRM implementation and transboundary cooperation.
United Nations / UN-Water (copy hosted by IDRA), published 2026
UN-Water's ten-year review of SDG 6. Source of the 13% of countries and 10% of people with high or critical stress in 2022, regional increases 2015–2022, the Singapore case, IWRM progress and the 2049 projection, funding gaps, transboundary coverage by region, data gaps and the river-flow monitoring results.
United Nations University Institute for Water, Environment and Health (UNU-INWEH), 20 January 2026, published 2026
Launch of the UN University flagship report by Kaveh Madani. Source of the nearly 4 billion people facing severe scarcity at least one month a year, aquifer, lake, wetland and glacier losses, land subsidence, drought costs, the share of food grown in stressed regions, the regional examples and the proposed policy shifts.
University College London (news release on a peer-reviewed Nature study, 24 January 2024), published 2024
Summary of the largest global analysis of in-situ groundwater levels (about 170,000 wells, 1,693 aquifer systems). Source of the shares of aquifers declining and accelerating, the link to cropland in dry climates, the recovery cases and the data gaps in tropical Africa and Latin America.
UN-Water / FAO, published 2021
Source of the five categories used to classify SDG 6.4.2 values: no stress (0–25%), low (25–50%), medium (50–75%), high (75–100%) and critical (above 100%).