The 33-year-old said she knew that the race would be decided at the turnaround point of the 31km race.
“The route surface was divine,” said Sanders. “It was very fast and we also enjoyed full road closure, which is always great.
“The plan was to go out steady and drive it hard after the turnaround and I felt that I executed that well.
“I turned myself inside out and so it should be.
“My goal was certainly to podium and I tried hard for a gold medal but I was well aware of the strength of both Vera and Girubuntu.”
Namibia’s Vera Adrian (23) won gold with silver going to Rwanda’s Jeanne D’arc Girubuntu (21).
1. Vera Adrian (Nam) 46:47
2. Jeanne D’arc Girubuntu (Rwa) +1
3. Samantha Sanders (RSA) +11
4. Wogahta Gebrehiwet (Eri) +1:11
5. Mossana Debesai (Eri) +1:43
6. Aurelie Halbwachs (Mri) +2:04
7. Lise Olivier (RSA)+2:10
8. Helen Mitchell (Zim) +4:12
9. Eden Bekele (Eth) +4:16
10. Fatima Zahra El Hiyani (Mar) +4:31