Multisensor hydrometric station for detecting flash floods and torrential avenues in mountain rivers

Abstract

Stations in an early warning system monitor river water levels to detect the occurrence of flash floods or torrential avenues. To do so, they use ultrasonic sensors that measure the distance to the water surface; additionally, they may incorporate image capture systems to verify changes in the riverbed or integrate surface velocity radars that estimate water flow. To address the design of a monitoring station based on a low-cost, low-power microcontroller, the first phase proposes using an ultrasonic distance sensor, a rain gauge, and an external perimeter barrier—an electronic device that transmits measurements to a monitoring center located at considerable distances via GSM/GPRS and radio; in a second stage, following the monitoring of a mountain river for one year and the characterization of a flash flood, the addition of two ultrasonic sensors is proposed as a solution to morphological changes in the riverbed that affect the measurements. As a result, additional reference points are obtained that allow for the identification of increases in flow. It is concluded that the addition of ultrasonic sensors helps improve the identification of these natural phenomena and, consequently, reduces the risk of misinterpretation, especially when water level measurements are affected by morphological changes in the riverbed.