Transient flow in water distribution systems refers to the hydraulic response that occurs when a system operating under steady-state conditions is subjected to a disturbance and evolves toward a new equilibrium state. During this process, significant pressure fluctuations may develop throughout the network, potentially compromising the structural integrity and operational reliability of hydraulic infrastructure. The assessment of these phenomena is therefore essential for the identification of vulnerable components and the development of appropriate mitigation strategies. This thesis presents a transient flow analysis of a real water distribution network through numerical modelling. A hydraulic model was developed under steady-state conditions using EPANET, while transient simulations were performed using Python’s library TSNet based on the Method of Characteristics.