Micro hydropower (MHP) provides a viable renewable energy solution from which individuals, organisations and communities can also derive social value and benefits. Desk studies and literature reviews show limited studies that (a) quantify the social impact of MHPs in water networks and (b), establish evaluation methods for such analysis. To date, most studies relating to MHP projects have focused on physical and technological parameters, as well as cost and environmental factors that influence their design, installation, operation, and maintenance. Less attention has been given to the intangible social, political, and institutional considerations, which are also important for the acceptability and adoption of renewables such as MHPs, and for their performative longevity. This study addresses these gaps. The social return on investment (SROI) method was used as the basis to quantify the cost and social returns of three MHP demonstrators in a public and private water supply, and irrigation network in Europe. The value inputs and outputs from each case were analysed and a SROI range of between 2.6 and 5.8 euros for each one euro invested was determined. The findings were further evaluated using sensitivity tests. This work serves as a useful first step to establishing a SROI benchmark range for MHP schemes in water networks, extrapolatable for other renewable energy interventions. They also highlight the opportunities and challenges of quantifying and forecasting the social returns of MHPs to guide future work.