Underwater Sound in the Wadden Sea
In the Wadden Sea, we measure underwater sound generated by different types of vessels to better understand its effects on this unique ecosystem. There is still limited knowledge about sound propagation in very shallow water in particular. By measuring sound at carefully selected locations – from intertidal flats to deeper channels – we gain insight into how far sound can travel through the Wadden Sea and what role different vessels play in this.
- Client: Rijkswaterstaat
- Location: Waddenzee (Ports: Lauwersoog en Harlingen)
- Project period: 2022
The Wadden Sea is a dynamic and ecologically valuable area where various types of vessels use the navigational channels every day. Despite the increasing attention to underwater sound as an environmental factor, there is still limited understanding of how vessel noise propagates in shallow, tidal waters such as the Wadden Sea. This is particularly relevant where navigational channels meet surrounding sand and mudflats, combining high ecological sensitivity with human activity.
The increase in underwater sound and its potential effects are becoming increasingly apparent. Under the Marine Strategy Framework Directive (MSFD), the Netherlands is required to investigate the effects of underwater sound sources. One of the knowledge gaps concerns the impact of underwater sound in the shallow waters of the Wadden Sea and the individual contributions of specific vessels. This study provides a first assessment of underwater sound generated by vessels in the Wadden Sea.
As part of this project, acoustic measurements were carried out over a full week during the late summer season at multiple measurement locations, strategically positioned along so-called transects (lines perpendicular to the navigational channel). The measurement points varied in depth, from intertidal flats that fall dry at low tide to approximately 8 metres, and in distance from the navigational channel, up to a maximum of 3 kilometres. Measurements were conducted on both weekdays and weekends, during both daytime and nighttime, to obtain as comprehensive a picture as possible of underwater sound in the Wadden Sea.
The ultimate goal? To better understand the impact of vessel noise on the Wadden Sea, so that we can work with other stakeholders towards sustainable solutions and a good balance between nature and human use.
Take a look at our other projects
MUSA, Research into the behavior of mud-sand mixtures
MUSA, Research into the behavior of silt-sand mixtures Tidal basins and estuaries form an important transition zone between land and sea. These areas are vital for flora and fauna, but are also extensively used by humans, for example for shipping. For ecological and navigational purposes, it is important to understand how channels and shoals behave and what seabed compositions can be expected in different locations. The seabed in tidal basins and estuaries consists mainly of sand and silt. The channels are often sandy, whilst the intertidal zones are rich in silt. The interaction between sand and silt, combined with currents and waves, leads to a complex dynamic of migrating channels and banks in these areas.
Underwater sound DEMASK
The DEMASK project aims to develop and test policy scenarios for continuous underwater noise in the North Sea. Through measurements, the project investigates to what extent anthropogenic noise sources contribute to underwater noise and what impact this has on the marine ecosystem. With measurement setups on the bottom of the North Sea, long-term measurements are conducted, and data is collected that provides insight in the noise distribution in the North Sea.
Ecowende
Ecowende, a collaboration between Shell, Chubu and Eneco, is developing north-west Europe’s most environmentally friendly offshore wind farm at Hollandse Kust West. To minimise the impact on the marine ecosystem, extensive research is being carried out by WaterProof on the presence and behaviour of porpoises and underwater noise levels during the construction and operation of the wind farm. This research will provide essential knowledge for balancing sustainable energy production and nature conservation in the North Sea.
