Sustainable water supply solutions are essential for improving livelihoods in Zanzibar's fishing villages, where access to clean and reliable water is often limited. Theoretical analysis will be employed to evaluate various sustainable water supply solutions and their potential costs versus benefits for fishing village populations. The theoretical framework will provide policymakers and practitioners with a robust tool for evaluating sustainable water supply solutions tailored to the specific needs of Zanzibar's fishing villages. Recommendations include prioritising community engagement, integrating technological innovations, and implementing phased implementation strategies based on the cost-effectiveness analysis.