Indonesia is a country with high rainfall, the rainy season can last for four months in one year. The bad habit of people throwing garbage in waterways is also a
contributing factor to the cause of flooding. Floods bring a lot of problems in the
environment, especially in areas that are often prone to flooding. Therefore, an idea
emerged to create a monitoring device for a flood warning system using the iot
system and the Blynk application on a gadget. This study aims to make a means of
controlling and monitoring water level distances using an internet connection
system. The flood hazard early warning sensor will be designed using a water level
sensor, a microcontroller. The sensor used to measure the water level uses an
ultrasonic sensor, which is installed above the water surface by utilizing a
predetermined distance. The test results show that this system is able to provide
realtime information on water levels categorized as safe, alert, alert, and dangerous
conditions and broadcast via the Blynk application media. In addition, this research
contributes to the development of highly efficient technology at the JGU Campus
(Jakarta Global University).
Keywords: Flood, flood hazard early detection, Ultrasonic Sensor, Nodemcu Microcontroller, Internet of Things