Introduction
The expansion of Lerwick Port in the Scottish Shetland Islands is set to increase its capacity, allowing larger passenger, fishing, and offshore vessels to dock safely. At the heart of this project is a large-scale seabed material removal effort, led by Boskalis Westminster. The operation aims to remove approximately 450,000 cubic meters of seabed material, overcoming the challenges posed by a hard, rocky seabed using advanced dredging operations and carefully controlled blasting techniques, all while ensuring minimal impact on marine life.
Why Seabed Material Removal Is Essential
Lerwick Port plays a crucial role in the region’s economy, supporting passenger transport, fishing fleets, and the offshore energy industry. However, its natural seabed includes rocky layers that hinder navigation and restrict access to larger vessels. The ongoing seabed material removal is crucial for deepening the port, allowing it to accommodate larger ships and enhancing operational efficiency.
With a total of 450,000 cubic meters of material to be cleared, the project represents one of the most challenging undertakings in the area. The hard seabed demands specialized solutions beyond conventional dredging methods, requiring a combination of technology and expertise to ensure the project’s success.
Multi-Phase Dredging Operations
The seabed material removal is being carried out in three structured phases:
Phase 1 – Soft Material Removal
The operation began with the trailing suction hopper dredger Shoalway, which efficiently removed over 150,000 cubic meters of soft seabed material. This prepared the site for further, more intensive work.
Phase 2 – Hard Rock Excavation
Following this, the Magnor, a large backhoe dredger, started working on the harder sections of the seabed. It operates alongside the pusher tug Union Onyx and the Terraferre barge. These vessels coordinate complex dredging operations to safely and efficiently extract rocky material.
Phase 3 – Controlled Blasting
Once exposed, targeted sections of the seabed will be drilled to create holes for the placement of controlled explosives. This method fragments large rock sections into smaller pieces, which are then removed by smaller backhoe dredgers. The phased approach ensures that safety and environmental considerations remain paramount.
Advanced Equipment and Techniques
The challenging seabed conditions at Lerwick require cutting-edge equipment and highly trained crews. The combination of hopper dredgers, backhoe dredgers, tugs, and support barges reflects the innovative approach that Boskalis Westminster is applying. These dredging operations are carefully coordinated to maintain efficiency while minimizing disruptions.
Controlled blasting is used only where necessary, with strict safety protocols and monitoring. By breaking down rock in specific areas, the team ensures that excavation proceeds safely and without unnecessary damage to the surrounding seabed.
Protecting Marine Life
A top priority throughout the seabed material removal is safeguarding local marine life. Continuous monitoring ensures that operations comply with environmental standards. Precautionary measures, such as restricting blasting times and using noise-reduction technology, help reduce potential stress on aquatic species.
Environmental experts collaborate with the project teams to ensure that the port expansion meets both economic and ecological objectives.
Disposal of Removed Material
The extracted seabed material is transported to a designated disposal site north of the island of Bressay. Proper disposal practices are followed to prevent harm to the local ecosystem. The project’s logistical planning ensures that the removal and transport processes align with marine protection guidelines while maintaining efficiency.
Long-Term Benefits
Once completed, the seabed material removal will transform Lerwick Port into a deeper, more accessible hub capable of handling larger vessels. This expansion will enhance trade, tourism, and offshore energy operations in the region, while also providing safer navigation routes for ships.
The advanced dredging operations demonstrate how engineering expertise and environmental stewardship can work together to deliver sustainable infrastructure projects.
Conclusion
The seabed material removal at Lerwick Port is a landmark project that showcases innovation, precision, and responsibility. With the expertise of Boskalis Westminster and a structured approach to dredging operations, the port is being prepared to meet future demands. At the same time, strict environmental protections ensure that the surrounding marine life is safeguarded throughout the process. This project sets a benchmark for large-scale seabed excavation efforts in sensitive coastal regions.