Due to rapid development of economy in Taiwan, industrialization and urbanization have brought great pressure on environment. In particular, industrial pollution has immediate impact on residential areas because of location in the nearby areas. The conventional water sensing instruments, such as meters for pH and conductivity measurement are reliable. However, frequent manual calibration and cleaning are usually required, thus the manpower demand for maintenance is heavey. Also, monitoring instruments for regulatory items related to enforcement, such as heavy metals and chemical oxygen demand have disadvantages of large volume and high installation cost. Therefore, the conventional water sensing instruments are not suitable for application scenarios on widely installation and distribution. A compact, robust and reliable multi-task water monitoring instruments is needed for environemtal IoT applications. The project has achieved the following results: 1. Miniaturized water quality sensing components for pH, temperature, conductivity, chemical oxygen demand (COD), suspended solids (SS) and heavy metals by utilizing optical and electrochemical methods are developed. A small automated water quality monitoring system for detection of pH, conductivity, SS, COD and heavy metal featureing compact, durable, easy maintaineance and low cost is also developed by integrating microfluidic systems, chemical analysis, optical detection and signal processing circuits. 100 sets of the automated water quality monitoring system have been installed in the designated field. Each set of instruments on sites has been checked three times comparing to standard measurement methods by the third party and achieved 89.9 % of overall data quality satisfaction. 2. Up to now, 100 sets of water quality monitoring instruments have been installed on several sites of Taoyuan City, including part of Nankan creek River Basin, Guishan Industrial park and Hangzikou irrigation ditch. The systems have been operated continuously over 60 days and achieved 96% of complete transmission of water quality monitoring data. 3. The water quality IoT wireless communication module and data center system has been established and operated online. Combining the established deployment maintenance management system and water quality sensing data analysis and decision-making system, the platform can issue immediate alert on the Traceability and early warning for the potential pollution area.

water quality sensing, IoT technology on water quality sensing, field demonstration