We have been carrying out Underwater Noise Assessments since 2008, for the full life cycle of offshore projects. We provide scientifically robust studies and services to meet our clients’ requirements including: provision of instruments, experienced offshore acoustic technicians, impact assessment and comprehensive reporting.
For underwater noise monitoring, we can provide two types of equipment, dependant on the scope of the survey required:
- SOFAR System: Developed in-house by Gardline, this calibrated system is used to collect recordings of underwater sound from industrial processes such as wind farm pile driving, subsea drilling activities or aggregate extraction, as well as ambient noise measurements.
- Autonomous Recording Units (ARUs) used for continuous recording of short or longer term events or baseline studies
For underwater noise modelling, we can utilise our proprietary modelling software, Gardline’s 360M to generate a two-dimensional noise map model, predicting the geographical distribution of sound energy in the water column.
The program is based on the parabolic equation solution to the wave equation and is an efficient class of models for low-frequency sound sources in range-dependent environments. The acoustic footprint of the noise source is computed based on the sound propagation in discrete angular directions from the point location in 360 transects, providing a full noise distribution map.
If available, additional client provided datasets (such as bathymetry, geological parameters, noise source characteristics, source depth and CTD data) can be included within the 360M model to generate a site and project specific noise propagation model bespoke for our client’s needs.