| 100% | ELBE | 4 | River into which the Vltava flows |
| 79% | WESER | 5 | River into which the Fulda flows |
| 75% | OHIO | 4 | River into which the Big Sandy flows |
| 75% | OHIO | 4 | River into which the Great Miami flows |
| 72% | OHIO | 4 | River into which the Big Sandy and the Little Sandy flow |
| 70% | ERIE | 4 | Lake into which the Detroit River flows |
| 66% | VICTORIA | 8 | Lake —, body of water in Africa into which the Kagera River flows |
| 62% | ELBE | 4 | Hamburg's river which flows into the North Sea |
| 61% | STYX | 4 | River into which the infant Achilles was dipped |
| 60% | SUSQUEHANNA | 11 | US river flowing into the Chesapeake Bay upon which Harrisburg, Pennsylvania stands |
| 57% | OSAGE | 5 | — River, tributary of the Missouri River, US, which flows into the Lake of the Ozarks reservoir |
| 57% | ARAL | 4 | Sea into which the Amu Darya flows |
| 57% | ATLANTIC | 8 | Ocean into which the Amazon River empties |
| 57% | ATLANTIC | 8 | Ocean into which the Orinoco River empties |
| 57% | ARCTIC | 6 | Ocean into which the Ob River empties |
| 54% | ERIE | 4 | Lake which the Detroit River flows to |
| 54% | LAOS | 4 | Land through which the Mekong River flows |
| 54% | AISNE | 5 | River flowing into the Oise |
| 53% | EBRO | 4 | The Aragón River flows into it |
| 53% | BLACKSEA | 8 | The river Danube flows into it |
| 53% | ERIE | 4 | The Detroit River flows into it |
| 52% | CRIMEARIVER | 11 | The Chornaya, which flows into Sevastopol Bay? |
| 51% | OSAGE | 5 | River that flows into the Lake of the Ozarks |
| 51% | TEES | 4 | River that flows into the North Sea at Middlesbrough |
| 51% | GANGES | 6 | River out of which the Padma flows |
| 51% | CHERWELL | 8 | Oxfordshire river that flows into the Thames |
| 51% | CASPIAN | 7 | Sea that the River Volga flows into |
| 50% | JORDAN | 6 | Sacred river flowing into the Dead Sea |
| 50% | PARNAIBA | 8 | Brazilian river that flows into the Atlantic Ocean |
| 50% | AAR | 3 | Swiss river that flows into the Rhine (Var.) |