Ballast Water Management in the North Sea: What To Do?

The entry into force of the Ballast Water Convention (BWC) is approaching quickly. On the 8th of September 2017, all ships world-wide are required to establish measures for ballast water management.

For existing ships, temporary measures have been arranged for the BWC application. Postponement of the obligation use Ballast Water Treatment Systems (BWTS) can apply to five years after entry into force date at the latest. Ships with such a postponement are temporarily allowed to perform Ballast Water Exchange (BWE).  For the North Sea region, the OSPAR Commission[1] has appointed BWE areas where ships with such temporary exceptions can perform BWE. A dedicated, regional approach was necessary because, according to regulation B-4 of the BWC, BWE can only take place at a minimum of 200 nautical miles from the nearest land and in at least 200 metres water depth. Since these circumstances are absent on the North Sea, a special temporary measure was designed to enable BWE on the North Sea. The resulting BWE area for the North Sea is illustrated below.

north sea ballast water

When applying BWE and using this map, please note that:

  • BWE is not allowed in the ARI > 0.75 areas;
  • Within, the Traffic Seperations Scheme (TSS), BWE is also allowed;
  • An exact description of the North Sea BWE area with coordinates in latitude and longitude for use in board can be found here;

OSPAR has applied two leading principles for temporarily allowing this BWE:

  1. The region must have a relatively low risk for introduction of invasive species BWE: only in areas with a low risk index (ARI). Clarity of water, chlorophyll concentration, distance to land and water depth are the most important parameters for designation of the risk index;
  2. The region must on the other hand enable shipping traffic in the Hamburg – Le Havre Range (correction for the so-called ‘Kompromisslinie’) to perform BWE.

During IMO MEPC 71 from 3-7 July 2017, a proposal will be discussed to possibly postpone the requirements for using BWTS for existing ships for a longer period than five years.

OSPAR Convention
[1] - OSPAR Convention for the protection of the Marine Environment of the North-East Atlantic, meeting of the OSPAR Commission, Cascais Portugal, 23- 27 June 2014

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