Thailand experiences heavy rainfall during the monsoon season, which can lead to flooding and water management challenges. To monitor these events, a national network of rain gauges, radars, and river measurement equipment works closely with universities and government agencies. This project focuses on two innovations to improve monitoring. First, OpenRiverCam (ORC), an open-source visual system that uses cameras and particle image velocimetry to measure river flows accurately and affordably. Second, a radar calibration method is developed to convert radar reflectivity into accurate precipitation measurements in millimeters. By implementing these systems, rainfall and river discharge can be better predicted and managed, improving both efficiency and cost-effectiveness in water management. The project also evaluates the applicability of ORC in Thailand and develops streamlined methods for analyzing historical rain gauge data, enabling Kasetsart University to perform future calibrations and make informed decisions.