Semantic search
- Salween River
- Samur Basin
- San Juan Basin
- San Martin Basin
- Sanaga Basin
- Santa Rosa Plain Groundwater Subbasin
- Sarata Basin
- Sarstun Basin
- Sassandra Basin
- Sava Basin
- Schelde Basin
- Sea
- Sea of Galilee (Kinneret)
- Seine Basin
- Sembakung Basin
- Senegal Basin
- Senegal River
- Sepik Basin
- Serrano Basin
- Shu-Chu Basin
- Sixaola Basin
- Skagit Basin
- Song Vam Co Dong Basin
- Sonoma Creek
- Sonoma Valley Groundwater Subbasin
- St. Croix Basin
- St. Croix River
- St. John Basin
- St. John Basin (Africa)
- St. John Basin (North America)
- St. Lawrence Basin
- St. Paul Basin
- Stikine Basin
- Struma Basin
- Suchiate Basin
- Sujfun Basin
- Sulak Basin
- Susquehanna River
- Syr Darya (River)
- Syr Darya Basin
- Tafna Basin
- Tagus (Tejo) Basin
- Taku Basin
- Talas Basin
- Tami Basin
- Tana Basin
- Tano Basin
- Tarim Basin
- Temash Basin
- Terek Basin