The objectives of this research were to design and develop an automatic water level warning system for communities living along Khlong Lad Phrao (Lad Phrao Canal) in Bangkok. The development of the system was divided into the following four main parts: 1) a water level measurement system; 2) a precipitation measurement system; 3) a water quality testing system covering dissolved oxygen, pH, turbidity and electrical conductivity and 4) an internet alert system utilizing the LINE application and web-based application information display. The first three parts were to be solar-powered. The design and development effort showed that the system successfully measured water levels along with water quality with speed and precision. Moreover, the system was easy to measure results and was able to alert through the LINE application when water in Khlong Lad Phrao approached critical levels, thereby reducing damage from water levels. Precision testing of the developed water level and quality measurement systems found that precision was in the range of 99.74-99.77%.