The data generated to support the findings of this study are available in an online data repository at zenodo.org at https://doi.org/10.5281/zenodo.3521933. Third party data used in this study are available as follows. Hydrological basin boundaries5 used in this study are available online at http://www.fao.org/nr/water/aquamaps/. Mountain definition data6 used in this study are available online at https://ilias.unibe.ch/goto_ilias3_unibe_file_1047348.html. Precipitation and evaporation data used in this study32 are available online at https://cds.climate.copernicus.eu. Snow cover data used in this study7 are available online at https://nsidc.org/data/MOD10CM. Glacier volume data48 used in this study are available online at https://doi.org/10.3929/ethz-b-000315707. Glacier mass balance data17,49 are available online at https://wgms.ch/. Lake and reservoir storage data50 used in this study are available online at https://www.hydrosheds.org/pages/hydrolakes. Water demand data used in this study are available upon request from Y.W. (wada@iiasa.ac.at). BWS data38 used in this study are available online at https://www.wri.org/aqueduct. GE data39 used in this study are available online at https://info.worldbank.org/governance/wgi/#home. Data on hydro-political tensions for transboundary river basins37 used in this study are available online at https://transboundarywaters.science.oregonstate.edu/content/transboundary-freshwater-spatial-database. Data for future projections of population count9 used in this study are available online at ftp://ftp.pbl.nl/hyde/SSPs/SSP2/zip/. Data for future projections of GDP41 used in this study are available online at http://www.cger.nies.go.jp/gcp/population-and-gdp.html. Data for future projections of temperature and precipitation40 used in this study are available online at https://climexp.knmi.nl. An online interactive visualization of the water tower index and vulnerability is available at https://www.nationalgeographic.com/environment/perpetual-planet/.