Based on MERIT DEM (Yamazaki et al., 2017) and MERIT Hydro (Yamazaki et al., 2019). This collection uses the native 3 arc-second grid, approximately 90 m at the equator.
A further collection is planned on finer terrain: HydroSHEDS v2 at 30 m. Compare the collections.
Pick any point on land. FullBasin tells you which drainage basin that point belongs to, exactly which land drains through it, and what that upstream land is like — its height, its steepness, its shape.
The river channels themselves: where each one runs, how the reaches connect, and what flows through them.
The terrain and the baseline hydrography: dir, elv, upa, upg, wth, hnd. We do not redistribute any of them. Register on the MERIT Hydro page (CC BY-NC 4.0 / ODbL) and cite Yamazaki et al. (2019).
Everything computed on top of that grid: the basin and region masks, the per-pixel upstream index, and sixteen upstream attributes — released under CC BY 4.0 with a DOI.
Because the two sit on the same 3 arc-second grid, they line up pixel for pixel. So FullBasin can tell you exactly which MERIT tiles a basin needs, before you download anything.
Point your phone’s camera at the code, then tap the link that appears.
fullhydro.org