Design and Development of an Internet of Things (IoT)-Based Water Level Monitoring System for Flood Early Warning at Lempake Dam

Abstract

Floods are among the most frequent natural disasters in Indonesia, often causing significant damage to communities and infrastructure. Monitoring the water level at the Lempake Dam is still carried out manually, resulting in delays in obtaining early flood information. This study aims to design an Internet of Things (IoT)-based water level monitoring system as an early flood warning tool. The system uses an ESP32 microcontroller and a JSN-SR04T ultrasonic sensor to measure water surface levels in real time. Measurement data are displayed on a 16x2 I2C LCD and sent to Firebase for visualization on a web dashboard. The system is also equipped with LED indicators, a buzzer, and an automatic notification feature via Telegram when the water level exceeds the safety limit. The test results show that the system operates stably with a measurement accuracy of ±3 mm and provides rapid warning notifications < 2 second. Therefore, this system can assist operators in efficiently monitoring water conditions and support flood disaster mitigation efforts at the Lempake Dam.