Assessment updated: August 2026

Humanity has made substantial progress in access to drinking water and sanitation, but progress remains too slow and uneven to achieve universal access by 2030. Between 2000 and 2024, 2.2 billion people gained access to safely managed drinking water and 2.8 billion gained safely managed sanitation. Nevertheless, in 2024, 2.1 billion people still lacked safely managed drinking water, 3.4 billion lacked safely managed sanitation, and 1.7 billion lacked basic hygiene services at home. Only 56% of domestic wastewater was safely treated. Established hazards such as fecal and chemical contamination remain urgent, while pharmaceuticals, PFAS, antimicrobial resistance and microplastics create additional monitoring and treatment challenges. Microplastics are widely detected throughout the water cycle, but their effects on human health have not yet been established. (WHO/UNICEF Joint Monitoring Programme; UN Sustainable Development Goals Report 2025)

At the same time, climate change, population growth, urbanization, industrialization, land degradation and over-extraction are placing increasing pressure on water systems. Climate change is making the hydrological cycle more variable, although the effects differ by region and type of event. In 2024, only about one-third of the world’s river basins experienced normal conditions; the remainder were wetter or drier than normal, marking a sixth consecutive year of widespread hydrological imbalance. All glacier regions reported net ice loss for the third consecutive year. Flood and drought risks are shaped not only by climate, but also by land use, infrastructure, preparedness, poverty and the quality of water governance. (WMO State of Global Water Resources 2024)

Groundwater provides drinking water, irrigation and resilience during drought, but extraction exceeds recharge in many agricultural and urban regions. A global study using measurements from approximately 170,000 wells across 1,693 aquifer systems found that groundwater-level declines accelerated in about 30% of the systems for which long-term comparisons could be made. The same research documented cases in which declines slowed or reversed following reduced pumping, managed aquifer recharge or changes in water supply, showing that depletion is not always irreversible. (Nature)

Demand is as unevenly distributed as supply. Agriculture accounted for approximately 72% of global freshwater withdrawals in 2023, industry for 15%, and municipal and service uses for 13%. Water security is therefore inseparable from food systems, energy, land use, trade and patterns of consumption. Increasing agricultural water productivity, reducing losses in irrigation and municipal systems, reusing treated wastewater, and protecting groundwater and ecosystems will generally be more important than simply developing new supplies. (FAO)

Water also crosses political boundaries. Some 153 countries share rivers, lakes or aquifers with other countries, but in 2023 only 43 reported operational cooperation arrangements covering at least 90% of their transboundary basin area. Scarcity and pollution do not automatically cause conflict. The risk of instability increases when water pressure combines with unequal access, damaged or inadequate infrastructure, weak institutions, displacement and failures of cooperation. Conversely, fair and durable arrangements for sharing water, information, costs and benefits can strengthen resilience and peace. (UNECE and UNESCO; UNESCO World Water Development Report 2024)

The trajectory can still be changed. Established responses include universal WASH services, pollution prevention, wastewater treatment and reuse, improved irrigation, leakage reduction, groundwater regulation, managed aquifer recharge, watershed and wetland restoration, drought and flood preparedness, and stronger transboundary institutions. Desalination can diversify supplies in suitable coastal areas, but its energy requirements, costs, brine disposal and dependence on power and conveyance infrastructure limit where it is appropriate. Digital monitoring, remote sensing, low-cost sensors and artificial intelligence may improve forecasting and system operation, but they also create costs, capacity requirements and cybersecurity risks. Achieving sufficient clean water for all without conflict will depend on combining appropriate innovation with efficient use, ecosystem protection, durable infrastructure, adequate finance, local capacity and fair rules for allocating water within and across borders.

• Accelerate universal access to safely managed drinking water, sanitation and hygiene, giving priority to underserved rural communities, informal settlements, schools, health facilities, displaced populations and other vulnerable groups. Finance must cover operation, maintenance and workforce capacity as well as new construction.
• Prevent pollution at its source and expand wastewater collection, treatment and safe reuse. Strengthen monitoring and regulation of pathogens, industrial discharges, agricultural runoff, PFAS, pharmaceuticals, antimicrobial resistance and other emerging contaminants. Point-of-use treatment can provide an interim or emergency safeguard, but should not replace reliable public services.
• Improve water productivity and reduce avoidable losses. Priorities include irrigation modernization suited to local conditions, leakage detection and repair, industrial water reuse, reduction of food loss, and agricultural and urban development consistent with basin water limits.
• Regulate groundwater extraction, protect recharge areas and expand monitoring of aquifer levels and quality. Use managed aquifer recharge where hydrogeological conditions, water quality, long-term maintenance and community rights make it appropriate.
• Protect and restore watersheds, wetlands, floodplains, forests and other water-related ecosystems. Maintain environmental flows and incorporate natural water retention into drought, flood and infrastructure planning.
• Prepare simultaneously for droughts and floods. Expand hydrological monitoring, multi-hazard early-warning systems, climate-resilient WASH services, emergency supply plans and infrastructure standards that account for changing future conditions.
• Strengthen cooperation over shared rivers, lakes and aquifers through operational agreements, joint monitoring, data exchange, transparent impact assessment, dispute-resolution mechanisms and participation by affected communities. Early-warning tools can help identify potential pressure points, but should trigger local analysis rather than be treated as predictions of conflict.
• Align water allocation, pricing and subsidies with efficiency, equity and ecological limits. Reforms should protect the human right to water and sanitation and ensure that basic household needs remain affordable while discouraging excessive or wasteful use.
• Invest in open, interoperable water data and public accountability. Strengthen the capacity of utilities, basin authorities, regulators and local governments, and expand water literacy in schools, professional education and public decision-making.
• Evaluate emerging options—including advanced desalination, decentralized sanitation, precision irrigation, solar-covered canals, hydroponics, aquaponics, saline agriculture and AI-assisted management—against transparent measures of water saved, energy used, cost, reliability, water quality, ecosystem effects, local maintenance requirements and distributional impacts. Promising demonstrations should not be presented as scalable solutions until these conditions have been tested.

• Use the Water, Peace, and Security Partnership online Early Warning System to predict and prevent conflict.
• Increase R&D for lower cost of desalination.
• Invest in the development of saltwater and wastewater products such as fertilizer, algae (for biofuel and feeding shrimp), and recovering nitrogen and phosphorus.
• Implement WHO and UNESCO plans for universal water and sanitation access.
• Manage all aspects of water resources to promote efficiency, equity, and sustainable development (integrated water management) including improved rainwater management.
• Add water conservation in school curricula.
• Apply lessons learned from producing more food with less water via drip irrigation and precision farming.
• Create and promote smartphone apps to show water used to make products.
• Produce animal products from genetic materials without growing animals.
• Invest in seawater / saltwater agricultural development.
• Promote increased vegetarian diets.
• Mass-produce electrochemical wastewater treatment solar power toilets.
• Develop point-of-use water purification technology.
• Invest in hydroponics, aquaponics, and vertical urban agriculture installations in buildings
• Support research to address microplastic pollution.
• Cover canals and irrigation channels with solar panels to reduce evaporation and increase electricity production due to cooler microclimate next to a canal.
• Use oil pipeline technology to move water from surplus areas to drought-prone areas.
• Encourage the adoption of The Global Commission on the Economics of Water seven-point call to collective action.

Sub-Saharan Africa: Water is distributed unevenly across seasons and subregions, but inadequate access depends as much on infrastructure, service quality, finance and institutions as on physical availability. In 2024, 68% of the population used at least basic drinking-water services and 35% used at least basic sanitation. Coverage of safely managed services was substantially lower, at approximately 32% for drinking water and 26% for sanitation. Rapid population growth and urban expansion can offset improvements unless utilities and local governments extend and maintain services fast enough. (WHO/UNICEF regional analysis)

Climate variability makes this service deficit a resilience problem. In 2025, floods accounted for more than half of reported extreme-weather events across Africa, while drought affected more than 8.5 million people in East Africa. Only about 40% of African countries had multi-hazard early-warning systems. Groundwater can buffer dry periods and extend rural supplies, but large estimates of continental groundwater storage do not mean that the water is uniformly accessible, renewable, affordable or of suitable quality. (WMO State of the Climate in Africa 2025)

Many rivers and aquifers cross national borders. Hydropower and irrigation can create shared regional benefits, but weak impact assessment, data exchange and operating rules can also intensify disputes. The Nile Basin Cooperative Framework Agreement entered into force in October 2024, providing a legal basis for a permanent Nile River Basin Commission, although it does not bind countries that have not joined. The Africa Water Vision 2063, launched in 2026, provides a continental framework for water security, sanitation and cooperation, but implementation will require sustained finance for operations, maintenance, monitoring and local capacity as well as construction. (Nile Basin Initiative; African Union)

Middle East and North Africa: MENA is the world’s most water-scarce region, although exposure and institutional capacity differ sharply among countries. Average annual water availability is projected to fall below the absolute water-scarcity threshold of 500 cubic meters per person by 2030. Under current management practices, an additional 25 billion cubic meters per year could be required by 2050 to meet demand. Population growth, irrigated agriculture, groundwater over-extraction, urbanization and industrial demand are intensifying the pressure. (World Bank)

Wealthier countries have expanded desalination and wastewater reuse. These can strengthen coastal urban supplies, but desalination’s cost, energy requirements, brine disposal and dependence on power and conveyance systems limit its suitability. Agriculture accounts for more than 80% of water withdrawals in the Near East and North Africa, so new supply alone cannot close the regional gap. Groundwater regulation, irrigation efficiency, network-loss reduction and safe, fit-for-purpose wastewater reuse are equally important.

Water stress can aggravate existing political, economic and humanitarian pressures, particularly where conflict damages civilian water systems or prevents their operation and maintenance. Approximately two-thirds of the Arab region’s freshwater resources cross national borders, while less than one-third of its transboundary basin area is covered by operational cooperation arrangements. Durable water security requires protection of civilian WASH infrastructure, stronger agreements and data exchange, and allocation or tariff reforms developed transparently with affected communities and protection of basic household needs. (ESCWA)

Asia and Oceania: Asia and the Pacific has made substantial but uneven progress in water security. Improvements in drinking water, sanitation and the reduction of open defecation coexist with large inequalities between urban and rural populations, higher- and lower-income countries, and continental states and Pacific small island developing States. The Asian Development Bank reports major improvement in its composite regional water-security index since 2013, but this measure includes several dimensions of water security and should not be interpreted as equivalent to universal access to safely managed drinking water and sanitation. (Asian Development Bank)

Climate and ecosystem pressures are changing the geography and timing of water risk. Floods, droughts and tropical cyclones continue to produce severe losses across the region. All 23 glaciers monitored in High Mountain Asia lost mass in 2025. Glacier retreat changes seasonal runoff and increases hazards such as glacial-lake outburst floods, although its effects on water availability differ among basins and over time. In Pacific small island developing States, drought, groundwater over-extraction and sea-level rise increase the risk of saltwater intrusion into limited freshwater aquifers. (WMO State of the Climate in Asia 2025)

Seven of the world’s ten largest groundwater-withdrawing countries are in Asia and the Pacific. Aquifer monitoring, abstraction controls and recharge protection therefore need to be aligned with agricultural, energy and urban policy. Progress in safely treating domestic and industrial wastewater remains limited, and reporting is incomplete. Regional priorities include extending safely managed WASH, improving wastewater treatment and reuse, reducing urban and irrigation losses, restoring wetlands, protecting island aquifers, strengthening early warning and expanding cooperation over shared surface water and groundwater.

Europe: Europe has comparatively strong water institutions but increasingly volatile hydrological conditions. Water stress affects approximately 20% of its territory and 30% of its population in an average year. In 2025, 70% of European rivers had below-average annual flows. Low flows can constrain navigation, power-plant cooling and aquatic ecosystems, while floods and saltwater intrusion can disrupt water supplies and agriculture. Climate change intensifies these hazards, but land use, over-extraction, ageing infrastructure and the loss of wetlands and floodplains determine how severely they become shortages or disasters. (European Environment Agency; WMO European State of the Climate 2025)

Basic WASH coverage is high by global standards but is not universal. More than 16 million people in the pan-European region still lack basic drinking-water services and 29 million lack basic sanitation. Water quality is a wider systems challenge: only 39.5% of assessed EU surface-water bodies had good ecological status and 26.8% had good chemical status. Persistent pollutants heavily influence the chemical-status figure, while nutrient and pesticide pollution, altered rivers, over-extraction and incomplete wastewater collection and treatment remain important pressures.

Europe has mature legal and cooperative frameworks through the EU Water Framework and Floods Directives, the UNECE Water Convention and the Protocol on Water and Health. However, current river-basin measures are not expected to achieve full Water Framework Directive compliance by 2027. The 2025 European Water Resilience Strategy seeks to restore the water cycle, secure clean and affordable water, reduce leakage and improve EU water efficiency by 10% by 2030. Implementation will require basin-specific drought and flood plans, pollution prevention, wastewater upgrades, demand management, natural water retention and cooperation extending to shared aquifers and climate adaptation. (European Commission)

Latin America and the Caribbean: The region is water-rich in aggregate but highly unequal in where, when and to whom usable water is available. Approximately 150 million people live in highly water-scarce areas. Longer dry periods and more intense rainfall are disrupting drinking-water systems, agriculture, hydropower, navigation and ecosystems. Climate change interacts with urban growth, land-use change, over-extraction, degraded watersheds and inadequate storage. (World Bank)

In 2024, 140 million people—21.1% of the regional population—lacked safely managed drinking-water services, and 324 million lacked safely managed sanitation. Safely managed drinking-water coverage ranged from 83.1% in South America to 58.9% in the Caribbean and 49.2% in Central America. These averages also conceal substantial urban-rural, income and ethnic inequalities within countries. (ECLAC)

The Andes provide water to approximately 90 million people, and accelerating glacier retreat is changing the timing and reliability of runoff while increasing short-term hazards and longer-term supply risks. Caribbean small island developing States face additional exposure to drought, tropical cyclones, sea-level rise and salinization of freshwater resources. Priorities include maintaining and extending water and sanitation networks, financing utility operations and wastewater treatment, reducing losses, protecting aquifers and headwaters, strengthening drought and flood warning, and developing transparent allocation and tariff arrangements with social protection and meaningful participation by local and Indigenous communities. Desalination, transfers and reuse can contribute where appropriate but cannot substitute for basin governance and demand management. (WMO State of the Climate in Latin America and the Caribbean 2025)

North America: Water security in the United States and Canada is characterized less by aggregate continental scarcity than by regional mismatches among supply, demand, infrastructure and ecosystems. In the western United States and High Plains, warming, drought, changing snow accumulation and runoff, intensive irrigation and urban demand are placing pressure on basins where groundwater is already declining. Canada’s large freshwater endowment is also distributed unevenly: more than half of its surface freshwater drains northward, away from the most populated regions. Surface water and groundwater should therefore be managed as connected systems through basin-specific conservation, reuse, managed storage, ecosystem restoration and allocation reform. (USGS National Water Availability Assessment; Canada Water Agency)

Ageing infrastructure and unequal access remain important. EPA estimates US drinking-water capital requirements of $625 billion for 2021–2040. A separate assessment identifies $630.1 billion in wastewater, conveyance, stormwater and related clean-water infrastructure needs; these estimates cover different systems and should not be added together as one funding gap. In 2026, the Indian Health Service reported that approximately 41,000 American Indian and Alaska Native homes lacked adequate sanitation facilities, including more than 4,300 without safe water supplies and/or waste-disposal services. (EPA drinking-water assessment; EPA Clean Watersheds Needs Survey; Indian Health Service)

As of 13 August 2026, 40 long-term drinking-water advisories remained active on public systems in 38 First Nations communities in Canada, despite substantial progress in resolving previous advisories. The Canada Water Agency and the ten-year Freshwater Action Plan strengthen federal coordination, monitoring and ecosystem restoration, while the International Joint Commission provides an established institution for Canada–United States cooperation. In the Colorado River Basin, post-2026 operating rules will test whether reservoir operations, allocations, conservation and environmental flows can be aligned with more variable supplies and meaningful participation by Tribes and Mexico. Across the region, durable water security will require sustained maintenance, contaminant control, recognition of Indigenous rights and jurisdiction, demand management across agriculture, energy and digital infrastructure, and transparent basin data and allocation rules. (Indigenous Services Canada; U.S. Bureau of Reclamation)

Global Challenge 2 Video

Video Transcript: Clean water — How can everyone have sufficient clean water without conflict?

Global warming and population growth are intensifying the global water crisis. Increasingly severe droughts and floods, declining water tables, and diminishing soil moisture are threatening life on Earth. With 30% of the world’s largest groundwater systems being depleted and water tables falling on all continents, the risk of conflict over water resources is growing. By 2025, half of the world’s population could face water scarcity, and water consumption is unsustainable for 500 million people.

What is important to keep in mind today to prepare for tomorrow is that:

• 30% of the world’s largest groundwater systems are being depleted.
• 40% of humanity depends on water from watersheds controlled by other countries, raising the risk of conflict.
• Half of the world’s population could live in areas experiencing water scarcity by 2025.
• 3.4 billion people lack safely managed sanitation services, while 1.9 billion lack basic hygiene services.
• 367 million children attend schools without toilets, highlighting a significant global sanitation challenge.

If over 90% of the world now has access to improved drinking water—an improvement from 76% in 1990—what actions will help address this challenge?

• Investing in research to reduce the cost of desalination is crucial to making this technology more accessible, especially for regions facing severe water scarcity.
• Implement WHO and UNESCO plans for universal water and sanitation access. Adopting these plans globally would ensure that everyone has access to clean water and proper sanitation, reducing the spread of water-related diseases and improving overall public health.
• Investing in seawater agriculture could reduce freshwater demand, sequester $\text{CO}_2$, and provide sustainable sources of food and biofuel, making this a highly promising solution for the future.
• Produce animal products from genetic materials without growing animals. This innovative approach could dramatically reduce water usage, land usage, and greenhouse gas emissions, offering a sustainable alternative to traditional livestock farming.

In conclusion, the global water crisis is a pressing issue exacerbated by climate change, population growth, and industrialization. The report emphasizes the importance of sustainable water management, technological innovation, and international cooperation to ensure that everyone has access to sufficient clean water without conflict.

To know more about clean water, go to The Millennium Project website: www.millennium-project.org. To see how this fits into the global situation and future possibilities, see the State of the Future 20.0, available on The Millennium Project website.