Route planning in a changing maritime environment
The phrase ‘Finland is an island’ is familiar to all of us. About 96% of Finland’s foreign trade is transported by sea. This is widely known, but how many people think about what it means in practical terms for the commercial maritime routes and what kind of planning is required behind it? The fleet that also operates to Finland is undergoing significant changes. Always tightening climate and emission reduction targets are increasing the size of vessels and their ice-going ability is weakening due to lower engine power. The new vessels are both wider and longer than before. In addition, the entire maritime environment is digitalizing and automation is increasing. These changes create pressure to develop and improve the waterway infrastructure.
Wind farms and safety in maritime route planning
The boom of offshore wind power plants that has continued for a long time in Europe and elsewhere in the world has also found its way to the Baltic Sea. The Baltic Sea is small and shallow, its average depth is only 54 meters. Suitable locations for wind farms must be carefully coordinated with existing routes following authority guidelines. The optimal location for wind farms in terms of seabed topography and quality may however be challenging from both maritime traffic and nature conservation perspectives. Coordinating these issues requires a lot of different studies, permits, and cooperation with various parties. Maritime safety cannot be compromised under any circumstances.
Planning and developing maritime routes must consider the needs brought by different seasons. The annual freezing of the Baltic Sea, especially in its northern parts, creates its own challenges. As the size of vessels increases, their maneuverability in icy conditions becomes more difficult and the channels made by current icebreakers are not wide enough. Large vessels may require two icebreakers to assist simultaneously, and in route planning, sufficient space for safe assistance must be considered. Development work is also hindered by the reduced predictability of winter conditions due to climate change. Wind farms change ice dynamics and may complicate winter navigation by generating more packed ice.
Development of marine surveying supports maritime route planning
Marine survey data is the foundation of route planning. Completely new commercial shipping routes are rarely designed, but maintenance dredging to the charted depth is needed regularly. The increase in vessel size also creates needs for route development. The depths of the routes may be sufficient, but their geometry and markings may need to be changed to suit updated needs. Due to larger vessels, sharp bends need to be softened and turning areas expanded to ensure safe traffic. Developing technology creates more opportunities to add intelligent maritime safety devices and develop their remote control. Disruptions to satellite positioning and wireless communication remind us of the necessity of traditional route markings.
Marine survey data must be updated due to both natural and human-caused seabed changes. In addition, the growing requirements for survey data brought by technical development create needs for new seabed surveys. The development of marine surveying has been fairly rapid since the 1990s. The accuracy of positioning methods has significantly improved. Previously, the positioning accuracy of surveys could be several meters, but nowadays it is, at best, only a few centimeters. Simultaneously, the point density of echo soundings has exploded. Nowadays, nearly all routes and port areas are surveyed with comprehensive multi-beam echo sounding, but the required water depth is still ensured with mechanical pole sounding when necessary.
Emmi Huvitus, Team Leader, Ports and Waterways, emmi.huvitus@sweco.fi
Anneli Lindblad, Project Manager, anneli.lindblad@sweco.fi
Timo Halonen, Specialist, timo.halonen@sweco.fi