Data sources

The rivers

Each river is a Wikidata item (CC0) with articles in at least two Wikipedias. From Wikidata come the names in seven languages, the length, the flow, the basin area, the mouth and the source, the countries and the tributaries. No Wikipedia text is copied.

The drawing and the profile

Each river is followed reach by reach along the RiverATLAS network (HydroATLAS v1.0, CC BY 4.0, Linke, Lehner et al. 2019), from the source to the mouth that Wikidata gives. The profile is the lowest altitude of each reach's catchment, which is close to the water level. We do not use HydroRIVERS, HydroBASINS or GloRiC: their WWF licence has clauses a public site with advertising cannot meet.

The water, month by month

The average flow, the lowest and the highest month come from the WaterGAP model in RiverATLAS (1971–2000). Which month is which is estimated from the rain, temperature and snow along the river (WorldClim, also in RiverATLAS). It is an estimate, and the page says so.

The basin in numbers

People, land cover, protected areas, lakes, glaciers, permafrost and the degree of regulation by dams are the RiverATLAS figures for the whole basin upstream of the mouth (CC BY 4.0).

Towns, bridges and dams

Towns and cities within 2–4 km of the river come from GeoNames (CC BY 4.0); the cities, bridges, dams, locks and World Heritage sites that Wikidata links to each river come from Wikidata (CC0). Each is placed at its kilometre from the source.

Along the river

Dams, weirs, locks, waterfalls, rapids, boat ramps, canoe put-ins, ferries, marinas, river beaches, viewpoints and castles are counted from OpenStreetMap in a corridor around the river (© OpenStreetMap contributors, ODbL). They appear only inside the pages.

Images

The source and the mouth seen from space come from the Sentinel-2 cloudless 2016 mosaic by EOX (CC BY 4.0; later years are non-commercial and are not used). Photos come from Wikimedia Commons, only with free licences, with the author and licence under each one. The world map of rivers on the home page is drawn from RiverATLAS.