Underwater sound from anthropogenic sources and its potential adverse effects on the marine environment is a topic of much global interest. This article gives an overview of known sound source levels for various dredging equipment and activities and describes a method used to extrapolate source levels.
Marine fauna is sensitive to underwater dredging sounds. Scientific research indicates that inducing the fauna to leave an area temporarily before the start of a project minimises serious impacts. And the marine life returns when the dredging is finished.
TNO’s acoustic surveys of dredgers during all phases of the dredging cycle showed that permanent hearing threshold shift was not exceeded in any cases studied or in any species in question.