The recorded households in the Municipality of Aliaga, Nueva Ecija last 2024 were 19,853, with population steadily growing from 63,543 in 2015 to 70,363 in 2020. Water demand in this area also increases as the population grows over time and this raises concerns about the distribution system’s capacity. This study evaluates Aliaga’s water distribution system using demand forecasting and hydraulic simulation with EPANET-JS. In projecting water demand for 2030, 2035 and 2040, historical population and consumption data were used. The water distribution system was modelled using EPANET-JS comprising of 82.83 kilometers of pipes, 881 nodes, and five pumping stations and simulated under current and future demand scenarios. Performance was measured by the nodal pressure, velocity of the flow and headloss against hydraulic criteria. Results show that for the present water connections, 0.23% of nodes fall below minimum pressure and when considering the full household coverage, 39.61% of nodes are below minimum pressure, and by the year 2030 and 2040, this number rises to 53.35% and 62.43% respectively. This is due to the fact that water demand increases from 29.30 Ips (2025) to 135.65 lps (2040). By this time, future demand exceeds the 128.40 lps maximum production of water sources in Aliaga. Flow velocities are tolerable at maximum of 3.4 m/s from 1.74 m/s. In contrast, headloss in pipes outside the parameters increases from 5.33% to 20.54%. Areas served by newer infrastructure maintain adequate performance, but older sections experience deficiencies due to small pipes and insufficient pumping capacity. The study identifies critical improvements: interlooping the distribution system between Brgy. San Carlos and Brgy. Bibiclat with 150mm PVC pipelines, upgrading Pumping Stations 2 and 4, and upsizing transmission lines from 100mm to 150mm in Brgy. San Juan to Brgy. San Felipe and from Brgy. San Pablo to Sto. Tomas. The current infrastructure system is sufficient for the existing connections, but upgrades are needed to maintain reliability in the service area considering the future demands.