Safe water, sanitation, and hygiene (WASH) is critical for the prevention of postpartum infections. The aim of this study was to characterize the WASH conditions women are exposed to following cesarean section in rural Rwanda. We assessed the variability of WASH conditions in the postpartum ward of a district hospital over two months, the WASH conditions at the women's homes, and the association between WASH conditions and suspected surgical site infection (SSI). Piped water flowed more consistently during the rainy month, which increased availability of water for drinking and handwashing (p < 0.05 for all). Latex gloves and hand-sanitizer were more likely to be available on weekends versus weekdays (p < 0.05 for both). Evaluation for suspected SSI after cesarean section was completed for 173 women. Women exposed to a day or more without running water in the hospital were 2.6 times more likely to develop a suspected SSI (p = 0.027). 92% of women returned home to unsafe WASH environments, with notable shortfalls in handwashing supplies and sanitation. The variability in hospital WASH conditions and the poor home WASH conditions may be contributing to SSIs after cesarean section. These relationships must be further explored to develop appropriate interventions to improve mothers’ outcomes.