| Final | time | L |  | 1. Helen Stewart | CAN | 1:07.7 |  | 2. Wanda Lee Werner | USA | 1:07.7 |  | 3. Virginia Grant | CAN | 1:08.3 |  | 4. Liliana Gonzaltas | ARG | 1:08.4 |  | 5. Gretchen Ann Gluter | USA | 1:08.9 |  | 6. Sheely Mann | USA | 1:08.3 |  | 7. Elleen Holt | ARG | 1:09.3 |  | 8. Cristina Kujath | ARG | 1:10.7 |   
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| Heat 1 | time | Rk. |  | 1. Sheely Mann | USA | 1:07.1 | 1. |  | 2. Helen Stewart | CAN | 1:08.9 | 5. |  | 3. Gretchen Ann Gluter | USA | 1:09.0 | 6. |  | 4. Cristina Kujath | ARG | 1:10.6 | 8. |  | 5. Sara Barber Canada | CAN | 1:12.6 | 10. |  | 6. Wilma Luz | BRA | 1:13.5 | 11. |  | 7. Ruby Bonder | CHI | 1:16.0 | 12. |   
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| Heat 2 | time | Rk. |  | 1. Virginia Grant | CAN | 1:08.4 | 2. |  | 2. Liliana Gonzaltas | ARG | 1:08.6 | 3. |  | 3. Wanda Lee Warner | USA | 1:08.8 | 4. |  | 4. Elleen Holt | ARG | 1:10.5 | 7. |  | 5. Rebeca Colunga | MEX | 1:10.8 | 9. |  | 6. Gloria Botella | MEX | 1:16.4 | 13. |  | 7. Carmen Navarette | CUB | 1:18.6 | 14. |   
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