Preliminary analysis of water supply infrastructure vulnerability

Water is essential in human life. Safety measures are needed to ensure the security of the water supply system consistently. Vulnerability assessment of the water supply system considered the characteristics of the water supply system, risk analysis, and mitigation. This study aims to determine the initial conditions by analyzing the water supply against structural condition external influences on soil type and earthquake incidence. Data was collected from PDAM Kota Yogyakarta, then analyzed spatially by using descriptive statistics and compared to the strength of the material. The results showed that most of the water supply installed in the water supply system in Kota Yogyakarta has an age of more than 50 years. The city of Yogyakarta has an earthquake frequency that occurs 96 times/year. Thus, the infrastructure will be more susceptible to earthquakes, especially if the systems are in mountainous areas. Approximately 57% (522,9 km pipes) of the water supply system assets were laid in soil with a soil pH of 4.5 – 5.5 (latosol soil type). Latosol soil type has acidic properties 29,79% of pipes which is susceptible to corrosion. 46,49% of water supply pipes in Kota Yogyakarta are sensitive to earthquake incidence due to material and pipe age.