Fault tree and decision making trial and evaluation laboratory model for formulating risk mitigation strategies at water production process of PDAM Baubau

Water treatment plant (WTP) system which is oriented to knowledge, limited production operator, and improvised WTP equipment triggers risks. Risk is everything that hinders the achievement of a goal, where one of the goals of the WTP is to produce quality drinking water in terms of the production process. But in the production process, problems often occur such as pump damage, mixer damage and so on. The purpose of this research is to identify the causes of the risk of water quality failure using FTA and DEMATEL and the end result of which will be a risk mitigation strategy. Risk mitigation is a way to reduce the possibility of risk occurrence. Fault Tree Analysis (FTA) together with the Decision Making Trial and Evaluation Laboratory (DEMATEL) is used in identifying the risk of causality from the top to down and from the left to right. Risk assessment will use likelihood and consequence parameters consisting of 5 risks namely deteriorating water source quality, damage to mechanical components, operational errors, failure of quality control, and improper materials. Each of the five operational risks is sought from the top to down or vertically then the risk map is determined using the FTA, and 5 risk level groups that have a risk relationship from left to right horizontally by using DEMATEL. Based on a risk assessment, a risk mitigation strategy was formed in view of losses that could endanger the WTP. The results of the identification resulted in 2 risks included in high risk and 3 others are medium risk. The results of the risk classification have the potential for large losses and have a relationship between the risks. As for the risk mitigation strategy proposed one of them in terms of human resources (HR) is the performance of HR in the WTP must be improved such as implementing a "employee of the month"program, while from a technical perspective one of them is routinely monitoring good and true water quality analysis methods of raw and production water. This study also found a novelty side, namely the integration of the FTA and DEMATEL models which were proven to solve the problem.