Aqueduct 4.0: Updated Decision-Relevant Global Water Risk Indicators

This technical note introduces Aqueduct 4.0, a water risk framework by the World Resources Institute (WRI) that translates complex hydrological data into 13 indicators of global water risk. The framework utilizes the PCR-GLOBWB 2 model to analyze current conditions and project future water supply and demand across various climate scenarios for 2030, 2050, and 2080.

• Aqueduct 4.0 consists of 13 water risk indicators covering quantity, quality, and reputational concerns. To develop five of these indicators, the framework employed the PCR-GLOBWB 2 global hydrological model to create new datasets regarding water use and supply at the sub-basin level.
• The framework projects future sub-basin water conditions for the years 2030, 2050, and 2080. These projections are based on CMIP6 climate forcings and three distinct scenarios: optimistic (SSP 1 RCP 2.6), business-as-usual (SSP 3 RCP 7.0), and pessimistic (SSP 5 RCP 8.5).
• Current data indicates that 25 countries, representing 25% of the global population, face extremely high water stress annually. Approximately 4 billion people (50% of the global population) experience water stress for at least one month per year, a figure that may rise to 60% by 2050.
• High water stress is projected to impact $70 trillion in GDP (31% of global GDP) by 2050, an increase from $15 trillion (24% of global GDP) in 2010. More than half of this exposed GDP in 2050 is concentrated in four countries: Egypt, India, Mexico, and Turkey.
• The Aqueduct tool is intended as a prioritization tool and should be supplemented with regional and local deep dives, as certain elements like overall water risk cannot be validated because they cannot be directly measured.

APA

World Resources Institute (n.d.). Aqueduct 4.0: Updated Decision-Relevant Global Water Risk Indicators. https://www.wri.org/research/aqueduct-40-updated-decision-relevant-global-water-risk-indicators

Chicago

World Resources Institute. Aqueduct 4.0: Updated Decision-Relevant Global Water Risk Indicators. n.d. https://www.wri.org/research/aqueduct-40-updated-decision-relevant-global-water-risk-indicators.

Wikipedia

{{cite report |author=World Resources Institute |title=Aqueduct 4.0: Updated Decision-Relevant Global Water Risk Indicators |url=https://www.wri.org/research/aqueduct-40-updated-decision-relevant-global-water-risk-indicators |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{worldresourcesinstitutendaqueduct, author = {{World Resources Institute}}, title = {{Aqueduct 4.0: Updated Decision-Relevant Global Water Risk Indicators}}, institution = {World Resources Institute}, url = {https://www.wri.org/research/aqueduct-40-updated-decision-relevant-global-water-risk-indicators}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }