Optimization of the Disinfection Process in Potabilization Systems in Cuenca Alto Atoyac, Mexico

Abstract

Access to drinking water in Cuenca Alto Atoyac (CAA), serving over 3.5 million people, is challenged by contamination and inadequate disinfection processes. This study investigates the use of oxidation–reduction potential (ORP) as a tool to optimize disinfection in CAA’s water systems. The research was conducted in three stages: an initial pilot phase with 10 sampled sources, expanding to 14 supply sources in the experimental phase, followed by analyses defining optimal chlorine dosing and contact times across two distinct hydrogeological zones. Principal component analysis (PCA) identified key factors, explaining 53.52% of water quality variability, while ORP measurements revealed significant differences in water quality among sources, with “Ameca” and “Pozo #2 Santa María Atlihuetzían” representing the extremes. Adjusted chlorine doses and contact times were tailored to local conditions, achieving target ranges and ensuring improved microbial control. In the final stage, significant correlations were established between ORP levels, chlorine doses, and total coliform concentration, supporting the effectiveness of ORP in guiding disinfection processes. Overall, chlorine doses of 0.3–1.5 mg/L with contact times around 15 min yielded ORP values (594–687 mV) optimal for CAA water safety.