Using Maritime Boundaries as offshore location service (Jan De Nul Group) | Lifewatch regional portal

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Using Maritime Boundaries as offshore location service (Jan De Nul Group)

Jan De Nul Group is a global player in dredging and marine works. They are using a cluster of services to determine if the position of a ship is within a country's sovereign territorial seas. One of these services is Marine Regions’ Maritime Boundaries.

Keywords: Jan De Nul Group, Tax rates, Maritime Boundaries, Territorial Seas

"We need to determine if a ship is positioned within international waters. For this, we use Marine Regions services together with services from other providers."

Jan De Nul Group

Jan De Nul Group is the current market leader in dredging and marine works as well as a specialised provider of services for the offshore market of oil, gas and renewables. The Group is also a major player in civil engineering, environmental and brownfield development projects


The aim is to determine in which jurisdictional sea area a vessel is located. The United Nations Convention on the Law of the Seas (UNCLOS, 1982) defines several jurisdictional sea areas, such as the territorial seas, contiguous zones and exclusive economic zones. A coastal state has varying levels of sovereignty in these areas. In the territorial seas, for example, a coastal state has full sovereignty. These territorial seas stretch up to 12 nautical miles from the state’s coastline. The different jurisdictional regimes impact the vessels operating there in several ways, so it is crucial to know where they are situated relative to these maritime boundaries.

An example of this can be found in recent Dutch and Belgian legislation. This legislation establishes that vessels can only be considered as ‘sea-going’ when they are being used outside of the territorial seas for at least 70%. Whether or not a vessel is defined as ‘sea-going’ has implications for its tax rate.


Marine Regions provides global maps of the UNCLOS sea areas, among which the territorial seas. They can be downloaded freely from the Marine Regions website, but can also be accessed through web services (e.g. OGC WMS/WFS). By using these web services, the user is assured that he is using the latest version of these products, as they are updated regularly.

The Marine Regions layers can then be used as input to determine in which sea area a vessel is located, what legislation applies to the vessel in that particular area, and in the case of the Dutch/Belgian tax regulation, what tax rate is used.

Used components of the LifeWatch Infrastructure

MarineRegions’ Maritime Boundaries (Territorial Seas)

The purpose of Marine Regions is to create a standard, relational list of geographic names coupled with information and maps of the geographic location of these features. This improves access and clarity of the different geographic, marine names and allows an improved linking of these locations to databases to integrate biodiversity data, for example. Marine Regions is also providing the world’s EEZ boundaries. In the past decade the number of users has increased from a few hundred to more than one hundred thousand unique visitors per year. The Marine Region’s Maritime Boundaries and its unique identifier have become a standard for many users from academia, industry, and civil society. Today, the Maritime Boundaries dataset is used in various ways such as a geographic backbone for the World Register of Marine Species, as a geo-unit to calculate fishing activities, or as an assessment unit for the health of our ocean.


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