Global ~10km (5 arcmin) surface water quality data from the dynamical surface water quality model (DynQual) from 2005-2100, with annual and monthly temporal resolution. Simulations are made under three combined climate and socio-economic scenarios (SSP1-RCP2.6; SSP3-RCP7.0 and SSP5-RCP8.5) and using five general circulation model (GFDL-ESM4; UKESM1-0-LL; MPI-ESM1-2-hr; IPSL-CM6A-LR and MRI-ESM2-0), following the ISIMIP3b protocol (https://protocol.isimip.org/#/ISIMIP3b). Output data are provided at annual and monthly temporal resolution over WorldClim time periods (2005-2020; 2021-2040; 2041-2060; 2061-2080; 2081-2100). Output data includes: - Discharge (m3 s-1) - Water temperature (K)- Total dissolved solids (TDS) load (g s-1)- Biological oxygen demand (BOD) load (g s-1)- Fecal coliform (FC) load (million cfu s-1) - Salinity; as indicated by TDS concentrations (mg l-1) - Organic pollution; as indicated by BOD concentrations (mg l-1) - Pathogen/bacterial pollution; as indicated by FC concentrations (cfu 100ml-1)Note. A minimum discharge threshold of 0.1 m3 s-1 was used when computing TDS, BOD and FC concentrations, as uncertainties in absolute values of water availabilities have large impacts on resulting in-stream concentrations. Concentrations in these gridcells are assigned as NA.Full time series of these variables at 30 arcmin (0.5 degree) can be found at: https://zenodo.org/records/14677534.