Research Challenge: The central research challenge is to improve efficiency of measuring Assimilable Organic Carbon (AOC) in drinking water. This is crucial for several reasons. First, an accurate understanding of AOC levels provides insight into bacterial regrowth potential of drinking water, with implications for safety, infrastructure maintenance, and customer satisfaction. Existing methods to measure AOC are complex, time-consuming, and current proxy measurements are limited in their applicability across diverse water treatment methods. What Don't We Know: Currently, it is unclear whether the reported proxies for AOC measurement maintain their accuracy across various treatment trains. Furthermore, the specific physicochemical mechanisms affecting these proxy measurements are not fully understood. Methodology: -Conduct a comprehensive traditional literature review to establish a foundational understanding of the current state of AOC measurement and available proxies. -Experimentally compare proposed AOC proxy parameters with traditional methods to determine their limitations. -Investigate the physicochemical changes in AOC through oxidative treatment. -Test various coagulants to understand their effectiveness in reducing AOC levels and to identify potential proxies for AOC precursors. Impact: This project aims to create more efficient methods for AOC measurement, thereby enabling water utilities, both in the UK and internationally, to better monitor and mitigate bacterial regrowth challenges. The outcome will equip decision-makers and practitioners with more timely and accessible tools for infrastructure management and water quality assurance. Given the increasing demand for water and the complications introduced by climate change, this research holds significant global implications for the resiliency of water systems and public health.