Change of Chart Datum
In 2008, the Flemish Hydrography changed chart datum from MLLWS to LAT in order to meet the international decision to standardize the chart datum to LAT. More information on this change can be found in the brochure Transition from MLLWS to LAT.
Change of Coordinate System
In 2002, the Flemish Hydrography changed map projection coordinate system from ED 50 to WGS 84. This means that all positions published for the "Notices to Mariners" until the NtM 11 of 23.05.2002 are expressed in ED50. As of NtM 11 of 23.05.2002, all positions are expressed in WGS 84. The maps Flemish Banks D11, 101 (INT 1474), and 102 (INT 1480) are also expressed in WGS 84. However, some measurements made prior to this change are still displayed in ED 50. In this case, the exact position in WGS 84 can not be found on the map, but can only be determined from the text boxes.