Antwerp has completed its dredging work on schedule and container vessels drawing up to 13.1m of water can now enter and leave its Deurganck dock and Noordzee terminals independent of tidal conditions. Previously, only ships drawing 11.9m of water could do this.

For container vessels with a maximum length of 360m coming in with the tide, the maximum draught to the Berendrecht-Zandvliet lock remains 15.56m. For vessels proceeding to other destinations, such as the Deurganck dock, a greater draught is possible, provided there is a tidal window of at least one hour.

For incoming container vessels with a length of more than 360m, the maximum draught has been increased from 14m to 14.5m for a trial period. If the assessment is positive, the draught may be increased further at a later time.

For departing container vessels with a length of up to 340m going out with the tide, the new maximum draught has been increased to 15.2m, provided there is a tidal window of at least one hour. For vessels longer than 340m, the maximum draught has been increased from 14m to 14.5m during the trial period. If the assessment is positive, the draught may be increased further at a later time.

Thanks to the deepening of the Scheldt estuary, not only are greater draughts possible but also the tidal windows for tide-dependent vessels have been substantially increased by anything from 1.5 hours to 3 hours.

The situation for vessels heading into the port's inner terminals behind the Delwaide lock, including MSC's Home Terminal, is not so good, however.

Tide-independent navigation to and from the Zandvliet-Berendrecht lock complex depends on the lock thresholds (ie the minimum depth in front of the locks). The Scheldt estuary has been dredged down to 14.5m at chart datum (ie low tide), but since the Zandvliet and Berendrecht lock thresholds are only 12.89m at chart datum, tide-independent navigation of 13.1m is not possible there.

However, to limit this restriction, the joint Nautical Authority has come to an agreement with both the Flemish and Dutch pilotage services that arriving container ships proceeding downriver through the Zandvliet-Berendrecht lock complex may minimise keel clearance to only 1m instead of 10% of each vessel's draught.

In order to ensure full safety, this change only applies on a rising tide, and then only on condition that the lock thresholds are maintained at their maximum depth. The photo shows the MSC Beatrice (14,000TEU) passing through the lock in January 2010.

All ocean carriers may be happier than before, therefore, but they will still feel frustrated at having to wait for any tidal window, particularly as most modern container vessels have a design draught of at least 14.5m.

Full vessels arriving from Asia will seldom be loaded down this far due to most of their cargo being light, but the situation is different for departing vessels, particularly from Antwerp, which is often carriers' last loading port in northern Europe. Moreover, vessels are likely to get even bigger in the future.

Asked to comment on this situation, Eddy Bruyninckx, managing director of Antwerp Port Authority's management committee, opined: 'We can see that vessels are set to get bigger, but that does not necessarily mean that their design draughts will get deeper. They could get wider, for example.

'Moreover, our keel clearance in the Scheldt estuary is unusually large, and it is possible that this will be reduced in future - not just at the Zandvliet-Berendrecht lock complex.'

Source: CI Online