| 100% | AISNE | 5 | River flowing into the Oise |
| 71% | JORDAN | 6 | Sacred river flowing into the Dead Sea |
| 67% | SUSQUEHANNA | 11 | US river flowing into the Chesapeake Bay upon which Harrisburg, Pennsylvania stands |
| 64% | ERIE | 4 | The Detroit River flows into it |
| 62% | EBRO | 4 | The Aragón River flows into it |
| 62% | ELBE | 4 | River into which the Vltava flows |
| 62% | WESER | 5 | River into which the Fulda flows |
| 62% | NILE | 4 | World longest river flowing through Africa into the Mediterranean |
| 62% | OSAGE | 5 | River that flows into the Lake of the Ozarks |
| 62% | TEES | 4 | River that flows into the North Sea at Middlesbrough |
| 62% | OHIO | 4 | River into which the Big Sandy flows |
| 62% | OHIO | 4 | River into which the Great Miami flows |
| 60% | ILLER | 5 | River that flows into the Danube in the center of Ulm |
| 60% | CHERWELL | 8 | Oxfordshire river that flows into the Thames |
| 59% | PARNAIBA | 8 | Brazilian river that flows into the Atlantic Ocean |
| 59% | AAR | 3 | Swiss river that flows into the Rhine (Var.) |
| 59% | BLACKSEA | 8 | The river Danube flows into it |
| 58% | OHIO | 4 | River into which the Big Sandy and the Little Sandy flow |
| 56% | DART | 4 | River in Devon that flows into the English Channel at Dartmouth |
| 56% | ELBE | 4 | Hamburg's river which flows into the North Sea |
| 56% | DANUBE | 6 | Major European river that flows into the Black Sea |
| 55% | STOUR | 5 | River in Kent that flows into the English Channel at Pegwell Bay |
| 55% | PECOS | 5 | River from New Mexico that flows into the Rio Grande |
| 55% | ERIE | 4 | Great Lake that the Detroit River flows into |
| 55% | TRIBUTARY | 9 | River flowing into a larger one |
| 54% | URAL | 4 | It flows into the Caspian |
| 54% | MARNE | 5 | It flows into the Seine |
| 53% | VOLGA | 5 | Longest river in Europe that flows into the Caspian Sea |
| 53% | RHONE | 5 | River flowing into and out of Lake Geneva |
| 53% | OUSE | 4 | 143 mi. British river that flows into the Wash |