This project delves into the Singapore fifth NEWater plant, a crucial initiative for water conservation. Employing decision analysis methodologies, the project examines the plant's development and operational strategies, focusing on the application of decision analysis tools to a real-world problem. The study encompasses a detailed problem statement, objectives, and the construction of a decision tree to analyze the plant's structure with expected value analysis. It explores risk profiles, identifies key uncertainties, and evaluates multiple objectives and tradeoffs. The project uses publicly available information to provide recommendations, including the final conclusions regarding the plant's feasibility and effectiveness. The overall goal is to enhance understanding of decision analysis through practical application, contributing to water conservation efforts.