Semi-arid regions in Sudan are characterized by erratic rainfall patterns, leading to water scarcity and its impact on livestock health and productivity. Agricultural experts conducted a randomized controlled trial across five villages, assessing WHs' impact using baseline data for comparison. Water harvesting significantly improved milk yield by an average of 15% (95% CI: 8-23%) in the treated villages compared to control areas. The study supports the implementation of WHs as a crucial intervention for enhancing livestock productivity in semi-arid regions. Farmers should be encouraged to adopt water harvesting structures, and further research is recommended to explore long-term sustainability. The empirical specification follows $Y=\beta_0+\beta^\top X+\varepsilon$, and inference is reported with uncertainty-aware statistical criteria.