A sizable fraction of expensive resources such as water, gas, and electricity are lost in the process of distribution due to leaks, theft, and inefficiencies like aging infrastructure. Utilities worldwide are looking for solutions to localise losses and improve the overall efficiency of their distribution systems. The introduction of new sensing, communication, and control infrastructure in the next generation smart distribution networks offers hope that fine grained knowledge of the system will allow for more efficient operation. In this work, we present a novel loss localisation system that uses only a time series of inflow and outflow measurements to localise and quantify losses in tree distribution networks. The inflow and outflow measurements are used to set up a system of linear equations based on the principle of conservation of flows and these are solved to estimate loss rates of source destination paths and then localise losses on each internal link in the tree. We draw parallels with loss localisation in computer networks and show how ideas from network tomography could be applied in these settings. We demonstrate the efficacy of proposed estimators using preliminary simulation experiments. © 2014 IEEE.