Most of those installations can also be used for acoustic measurements such as Distributed Acoustic Sensing, DAS. The recent development of the technology, regarding both monitoring and analysis techniques, may give an additional method to study the seepage/internal erosion phenomena in dams and furthermore to provide information on the integrity.
The objective of this study is to make passive seismic measurements at a small dam to evaluate its sensitivity and its potential for subsurface dam monitoring. There are two passive seismic techniques that can be applied using DAS, seismic monitoring/imaging using recordings of the ambient noise field or monitoring of the sound of flowing water, making use of acoustic emissions. A technique known as ambient noise interferometry is used to analyse the noise recordings.