Water scarcity is an issue that countries are facing worldwide and at the same time the water demand is further steadily increasing. With these conditions leakages in a water distribution cannot be afforded. In this paper, we provide a method for determining the location of leakages using the hydraulic properties of a network. To that end, we utilize a self-adaptive reduced order network model to generate residual vectors and compare these vectors to expected residual signatures for various leakage scenarios. The novelty of this works lies in the construction of these residual signatures which is by a pressure variation model. Apart from that, the self-adaptive reduced order model is seen necessary as the pressure variations due to leakages are small, and therefore, models for residual generation must have minimum plant-model mismatch. Tests on an EPANET model of a hydraulic network which is part of the water distribution network in Randers, Denmark is presented to demonstrate the localization method.