The ISOE – Institute for Social-Ecological Research has conducted an in-depth analysis of the current state of global freshwater resources. The newly released study, The Status of Global Freshwater Resources, serves as a foundation for developing economic and innovation policies aimed at ensuring a secure water supply for the future. Commissioned by the Expert Commission on Research and Innovation (EFI), this study has been incorporated into the 2025 annual report presented today to German Chancellor Olaf Scholz. The report addresses, among other topics, innovations in the water sector.
Increasing pressure on global water resources
Worldwide, freshwater resources are facing growing pressure. Climate change is intensifying the global hydrological cycle, leading to more frequent and extreme droughts and floods. Simultaneously, societal shifts in water consumption are driving conflicts over access to these resources. Given these challenges, securing a stable water supply for the future remains a major concern.
„To develop adaptation strategies for changing global water dynamics, it is crucial to assess available water resources at both global and regional levels,“ says Robert Lütkemeier, head of the Water and Land Use research unit at ISOE. „A thorough understanding of water demand, quantity, and quality is necessary for economic and innovation policies to be effective.“
Global water stress varies by region
As part of the EFI report’s focus study on Innovations in the Water Sector, Robert Lütkemeier and co-author Ahmad Awad evaluated scientific knowledge on the status of global freshwater resources. The researchers analyzed observational data from platforms such as FAO Aquastat and EUROSTAT, alongside model data from the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP), which provides insights into past, present, and future conditions.
To estimate future water stress levels, the ISOE team conducted simulations of water withdrawals and compared them to available renewable water resources.
„Assessing water stress and predicting future changes remain uncertain due to limited observational data and potential socio-economic fluctuations,“ Lütkemeier emphasizes.
However, findings from The Status of Global Freshwater Resources indicate a decline in renewable water resources in arid and subtropical regions, such as the Mediterranean, while increases are expected in wetter temperate and monsoon regions.
„We must anticipate a rise in global water stress, though projections vary significantly from country to country,“ says Lütkemeier. „In Germany, reduced water withdrawals in the energy sector have helped lower overall water stress, yet regional differences remain. Water supply risks persist, especially as extreme weather events like droughts and floods—exacerbated by climate change—become more frequent.“
Only half of global water bodies meet quality standards
To assess water quality, ISOE researchers compiled indicators from the Sustainable Development Goals (SDG) monitoring program and data from the EU Water Framework Directive measurement programs. The results reveal significant regional disparities: globally, only 56% of water bodies meet general quality standards based on oxygen, salt, nitrogen, phosphorus content, and pH levels.
„Surprisingly, a significant proportion of poor-quality water bodies are found in the Global North, despite advanced wastewater treatment technologies compared to the Global South,“ reports Lütkemeier.
In contrast, the limited available data indicate relatively good water quality in sub-Saharan Africa.
In Germany, despite progress in combating pollution from chemical contaminants, nutrient loads, and legacy pollutants like mercury, many water bodies remain highly stressed. „Only 9% of surface waters meet good ecological standards,“ Lütkemeier states. „Additionally, groundwater in many regions is contaminated with nitrates and pesticides, posing risks to drinking water and ecosystems.“
Responsible water resource management
Authors Robert Lütkemeier and Ahmad Awad stress the urgent need for integrated and adaptable water management strategies.
„A responsible approach to water resources must address the impacts of climate change, account for future socio-economic developments, and curb pollution,“ says Lütkemeier.
Effective collaboration between stakeholders and governments is also essential. Policymakers must commit to long-term, impactful resource protection—not only through technological advancements but also via organizational and social innovations.
Ensuring sustainable water management for future generations also requires improving the quality and availability of scientific data. Particularly in already water-scarce regions, the lack of accurate data poses a critical challenge to securing future water supplies.
Original publication:
Luetkemeier, R.; Ahmad, A. (2025): The Status of Global Freshwater Resources. Studien zum deutschen Innovationssys – tem. Nr. 8-2025. Berlin: EFI.
