Putting wind farm installation noise to the test

Noise beneath the waves is an increasingly important consideration in offshore wind foundation installation, with new measurements from the Ecowende wind farm in the Dutch North Sea examining the sound produced by different techniques.

The first of what will be two reports analyses sound levels recorded during the installation of 52 monopile foundations by main contractor Van Oord. Six alternative techniques were used – three with CAPE Holland‘s vibro hammer and three using GBM Works‘ Vibrojet system – which combines vibration with water jetting. The campaign also included conventional impact piling with noise mitigation measures.

WaterProof Marine Consultancy & Services measured sound at distances ranging from a few m to as deep as 5 km. This covers different installation methods and mitigation configurations, including “bubble curtains”, an underwater system which releases a continuous wall of compressed air bubbles from a pipe or hose laid along the seabed. Hydro Sound Damper systems are another type of noise reduction technology that reduces loud underwater sounds during offshore construction.

The significance extends beyond environmental monitoring. Underwater noise can influence the choice of installation technology, the mitigation equipment required and the evidence needed to demonstrate compliance with project requirements. For contractors such as Van Oord, it is part of the wider engineering challenge of delivering foundations safely and efficiently while limiting environmental impacts.

This story was originally published by Project Cargo Journal. Read the full story at Project Cargo Journal →