Listening to Rivers: Using sound to monitor rivers

Abstract

From a babbling brook to a thunderous torrent, a rivers' soundscape can be described by many onomatopoeic words. Using sound produced sub-aerially by a river to calculate its stage is an entirely novel idea, designed to be used in an environment that is seldom monitored, headwater catchments. In these environments it is difficult to use traditional methods of automatic stage gauging, such as pressure transducers and ultrasonic depth monitors. I propose a cost-effective, simple to install sound monitor which can be simply placed beside a river that is making a noise. I develop a method of how to take the tempest that is river sound and filter it to a usable component using data collected from around the North East of England during Storm Ciara and Dennis, 2020. Understanding where river sound is generated from and the mechanisms behind it are key to developing sound monitoring which is why I use an experiment at a white water course to investigate the link between sound and river topography. Using an artificial channel and obstacles I investigate the link between obstacle height and configuration on the production of sound. To use river sound as a proxy for river stage, there has to be a process of how to setup and calibrate sound. I present a method of how one may go about setting up a sound monitor and the usage it may have in water resource management. Finally, I apply the method of sound filtering, river placement, and calibration at a catchment scale to determine its validity in river monitoring. Although novel, using sound to monitor a rivers' stage is practical and deployable.