Water quality modeling is essential for the management and operational control of water distribution systems (WDSs). The dynamic nature of these systems increases uncertainty about the permanent state of the network; therefore, conventional models are often insufficient to predict their behavior. In this study, a comprehensive literature review on water quality modeling in offline and online conditions, including classical models and real-time applications, is presented. The objective of this work is to classify and analyze these methodologies, identify knowledge gaps, and suggest directions for future research. The classification is divided into four categories: contaminant event detection, monitoring, contaminant source identification, and water quality simulation. The findings suggest that only approximately 20% of the articles analyzed address real-time applications. Consequently, there is a pressing need to strengthen the development of systems that integrate modeling, prediction, and control mechanisms to enhance water quality management.