| Answer | Crossword Clue |
|---|---|
| valleys | area drained by a river and its tributaries |
| drainage | the area drained by a river and all its tributaries |
| watershed | the area which a river and its tributaries drain |
| watersheds | WATERSHED, the area which a river and its tributaries drain |
| BASIN | Area drained by a river. |
| basin | area drained by a river |
| basinal | area drained by a river |
| basined | area drained by a river |
| basins | area drained by a river |
| subbasin | a section of an area drained by a river |
| subbasins | SUBBASIN, a section of an area drained by a river |
| watershed | An area or region drained by a river, river system, or other body of water |
| watersheds | An area or region drained by a river, river system, or other body of water |
