Developmental Strategies for a Water Quality Assessment Model with Limited Datasets – A Case Study from River Bhavani, India

Abstract

Understanding the significance of rational attributes for a water quality model depends largely on the availability and reliability of virgin datasets pertaining to their spatial-temporal variations and interactions. Present study aims to identify certain crucial attributes for deriving a water quality model for a selected reach of River Bhavani in Tamil Nadu, India using the results of the QUAL2K model based on a limited dataset. The spatial variations in the concentrations of inorganic suspended solids (ISS) and carbonaceous biochemical oxygen demand (cBOD) were studied in detail corresponding to the possible variations in other model parameters (pertaining to the hydraulic, environmental and climatic conditions). The results indicate that the cBOD has a significant dependency on temperature, dissolved oxygen and pH, while the ISS has shown more dependency on alkalinity, conductivity and bottom algae. It is further inferred that variations in pH and dissolved oxygen can impose triggering effects when external pollution loads (point and nonpoint sources) are introduced while generating the corresponding profiles of ISS and cBOD. Based on the results, the conceptual strategies for developing a data-limited model is presented, which can be further developed to simulate water quality profiles for similar data-limited scenario.