A comprehensive real-time water quality monitoring and control system to prevent seawater intrusion in the Sukreep Canal, Chonburi Province, Thailand

Water abstraction in areas impacted by saltwater intrusion threatens freshwater resources by compromising both water quality and availability. This study presents a real-time water quality monitoring and control system to address these issues, particularly in brackish canals where saltwater intrusion and freshwater abstraction are key concerns. This solar-powered system uses sensors to monitor key water quality parameters, including dissolved oxygen (DO), salinity, temperature, and pH, providing a reliable solution to mitigate saltwater contamination. Tested in Sukreep Canal, Chonburi Province, Thailand, the system underwent validation through comparisons with three types of water samples (drinking, canal, and saltwater), showing minimal error. Power and transmission tests demonstrated that the solar-powered battery charged within four hours, ensuring stable energy for continuous operation, and signal transmission remained consistent throughout the testing period. Over 30 days of field testing, temperature, pH, and DO remained within acceptable ranges, with only salinity exceeding the 30 ppt threshold. The system automatically continued pumping when salinity was within the acceptable range and stopped when salinity surpassed this threshold. The system is scalable and capable of long-term data storage for trend analysis, promoting sustainable freshwater management for agriculture and other sectors impacted by saltwater intrusion.