Dredging Ship at the Port of Zeebrugge, Belgium
Dredging is a complex, expensive and time consuming activity. Specialized
ships, like the one on the above photo, have been built for such a purpose.
Using a large suction head, the sludge is pumped into the ship until
capacity. The ship then sails to the designated dumping area to release
the sludge and goes back to its designated dredging area. The above
ship, the "Pallieter" (launched in 2004 and owned by the DEME group,
the world's third largest dredging company) has a carrying capacity
of 7,800 tons. This modern computerized dredging ship can perform very
precise dredging operations with a tolerance of 0.2 meters. This is
very important as dredging contracts stipulate that the contractor must
remove sediments up to a specified depth. If this depth is not serviced,
then the contractor is bound to redo the dredging at his own expense
until the contracted depth is met. Dredging beyond the specified depth
is also done at the contractor's expense since it will not been paid
for. With a crew rotation, the above ship operates 24 hours per day.