| 100% | AARE | 4 | It flows into the Rhine near Koblenz |
| 65% | GILA | 4 | It flows into the Colorado near Yuma |
| 60% | NORTHSEA | 8 | The Rhine flows into it |
| 55% | URAL | 4 | It flows into the Caspian |
| 55% | MARNE | 5 | It flows into the Seine |
| 54% | RHEIN | 5 | It flows into the North Sea |
| 54% | ARNO | 4 | It flows into the Tyrrhenian Sea |
| 54% | ODER | 4 | It flows into the Szczecin Lagoon |
| 53% | YAZOO | 5 | It flows into the Mississippi at Vicksburg |
| 53% | PLATTE | 6 | It flows into the Missouri south of Omaha |
| 52% | SEINE | 5 | It flows into the English Channel at Le Havre |
| 52% | LOIRE | 5 | It flows into the Bay of Biscay at Saint-Nazaire |
| 52% | AAR | 3 | Swiss river that flows into the Rhine (Var.) |
| 49% | ARNO | 4 | It flows near the Piazzale Michelangelo |
| 49% | TIBER | 5 | It flows near the Sistine Chapel |
| 48% | AVON | 4 | It flows near the Bard's home |
| 46% | SNOWY | 5 | — River, stream that flows into the Bass Strait near Orbost, Victoria, Australia |
| 46% | EMS | 3 | River rising in NW Germany that flows into the North Sea near Emden |
| 45% | EBRO | 4 | The Aragon flows into it |
| 45% | LAKEBIEL | 8 | The Aare flows into it |
| 45% | URAL | 4 | The Sakmara flows into it |
| 45% | OHIO | 4 | The Wabash flows into it |
| 45% | MOISIE | 6 | River in Quebec, Canada, that flows into the St Lawrence River near Sept-Iles |
| 43% | BLACKSEA | 8 | The river Danube flows into it |
| 43% | ERIE | 4 | The Detroit River flows into it |
| 42% | SAL | 3 | 482 mi. long river that flows into the Don and rises near the city of Elista in Kalmykia, Russia |
| 42% | EBRO | 4 | The Aragón River flows into it |
| 41% | SAONE | 5 | It flows into Lyons |
| 41% | AARE | 4 | It flows into Lake Brienz |
| 39% | AISNE | 5 | River flowing into the Oise |