Rites of passage: Restricted areas and the planning process
Commodore Nick Nash FNI looks at how seafarers navigate restricted areas, moving between many overlapping areas across a single passage
The integration of hydrographic data into ECDIS has led to restricted areas becoming more dynamic and layered. These areas – ranging from Traffic Separation Schemes (TSS) to offshore installations and environmentally sensitive zones – directly influence both route design and operational execution. This article looks at a passage plan from Southampton to Bergen via the North Sea to examine how restricted areas can be identified and managed using onboard ECDIS equipment.
by CommodoreNick Nash, CMMar FRIN FNI
The North Sea is one of the most regulated, structured and operationally complex maritime environments in the world. From the moment a vessel departs Southampton, mariners are operating within a framework defined not only by geography and traffic, but by a dense network of restrictions, obligations and protected zones. The passage to Bergen is shaped as much by where a ship must not go as by where it can. It is this distinction that lies at the heart of safe navigation.
Restricted areas across the North Sea take many forms. They include statutory exclusion zones surrounding offshore oil and gas installations, complex routing structures imposed by Traffic Separation Schemes and critical protections afforded to subsea cables and pipelines. Military exercise areas, often subject to change and activated through Notices to Mariners, add a further layer of complexity. Environmental designations such as MARPOL Special Areas increasingly influence both routing and operational conduct.
Setting out from Southampton
On leaving Southampton, the vessel immediately enters a tightly controlled navigational environment. The Solent demands precision and awareness, with constrained waters, crossing traffic and defined channels requiring strict adherence to established practice. As the vessel proceeds into the English Channel and integrates with the Dover Strait Traffic Separation Scheme, ‘restrictions’ become less about prohibition and more about compliance with structured movement. The mariner is part of a managed flow of traffic where deviation carries both risk and consequence.
On clearing the Dover Strait and entering the southern North Sea, the navigational picture begins to change. The density of offshore wind farms increases, often charted as areas to be avoided or approached with caution, while subsea infrastructure becomes more prevalent. Fishing adds a further hazard, not always formally restricted, but demanding equal respect. It is in this phase that the prudent navigator begins to widen margins, resisting the temptation to follow the shortest track, choosing instead one that preserves sea room and flexibility.
Critical central phase
The central North Sea is the most critical phase of the passage. Here, the density of offshore installations increases significantly, with large clusters of platforms, each surrounded by statutory safety zones, creating a complex and often congested operational picture. These zones frequently overlap or sit in close proximity, forming areas where a direct route is neither practical nor safe.
Military exercise areas may also be active within this region, requiring careful monitoring of Notices to Mariners and an understanding of the way they change over time. The navigator must move beyond simple route plotting and instead construct a deliberate corridor of safe water, ensuring that the vessel remains well clear of all restricted zones while retaining sufficient manoeuvring space. This is where the quality of passage planning really shows.
The North Sea’s designation as a MARPOL Special Area adds an additional layer of responsibility. Increasingly, restricted areas are driven not only by safety considerations but by environmental protection and regulatory compliance. These zones are monitored, enforced and, in many cases, expanding. The modern mariner must therefore navigate not only with precision, but with an awareness of the broader impact of their actions.
Nearing Norway
As the vessel approaches the Norwegian sector, the character of the passage changes once again. Environmental sensitivity increases, and coastal routing systems become more prominent. The approach to Bergen introduces narrower waters, increased traffic density and the influence of local pilotage.
Here, precision rather than wide margins is your key defence. The vessel must adhere strictly to charted routes while maintaining full situational awareness. The transition from open sea to confined coastal navigation demands a corresponding shift in mindset, where anticipation and preparation are critical.
Putting the route together
The entire process requires a structured and disciplined approach to voyage planning and verification. On the cruise ships that I work on, the initial route is constructed and electronically checked by the Voyage Planning Officer, using ECDIS to ensure that all charted restricted areas, safety contours and navigational hazards are correctly identified and avoided. The Deputy Voyage Planning Officer then reviews the plan independently, providing a critical second set of eyes to challenge assumptions, verify clearances and confirm that no restricted or cautionary areas have been inadvertently infringed.
The route then passes to the Environmental Officer to ensure full compliance with environmental regulations, MARPOL requirements and any applicable protected zones. This stage is increasingly important as environmental considerations expand across modern navigation. On other ships, of course, these tasks will need to be performed by the duty officers and the captain.
Only once these stages are complete can the plan be presented to the captain for final review and approval. This is a deliberate command decision where the overall strategy, margins and risk profile of the passage are assessed. The captain’s approval confirms that the route reflects both safe navigational practice and the operational intent of the voyage.
Following approval, the passage plan is formally presented at the pre-departure briefing to both the bridge and engineering teams. This ensures that all departments have a shared understanding of the intended route, where restricted areas are, and any operational considerations that may influence the passage. It reinforces Bridge Resource Management principles and promotes a unified approach, where awareness of restricted zones is maintained not only on the bridge, but across the wider ship’s operation.
A natural focal point
Throughout the passage, restricted areas must be clearly visible, properly understood and continuously monitored. Over-reliance on automation is a known hazard, and the mariner must ensure that safety contours, cross-track limits and alarm settings support, rather than replace, good judgement. This process must be supported by cross-checking with publications and Notices to Mariners, especially where dynamic or temporary restrictions may apply.
Restricted areas provide a natural focal point for team awareness and engagement. They should be clearly identified and discussed during the passage briefing, with an emphasis not only on their location but on their purpose. Understanding why an area is restricted reinforces compliance and supports better decision-making. The distinction between a hazard that may be managed and a boundary that must not be crossed is fundamental, and must be shared by the entire bridge team.
Restricted areas are not obstacles to be worked around at the last moment. They are the framework within which the entire passage is planned and executed. The professional mariner recognises this and responds accordingly, shaping the route with care, ensuring that every boundary is respected without compromise.