Mar 24 - 30, 2008

The 51 million Euro TRAILING SUCTION HOPPER DREDGER-ABUL, acquired by Karachi Port Trust (KPT) was out of commission due to mishandling of a minor fault by inexperienced staff hired from Pakistan Navy.

Actually, the dredger had developed a minor fault that became a major one following mishandling by inexperienced staff acquired from Navy which consequently led to a leakage in its engine room which allowed a gush of sea water into the dredger.

Informed sources told Pakistan & Gulf Economist that the KPT had inducted staff from Pakistan Navy at its TRAILING SUCTION HOPPER DREDGER-ABUL. The incharge of onboard personnel was Captain Izhar an Ex-GM Ship Repair at Karachi shipyard and engineering Works (KS&EW) who after retirement lobbied to get a job in KPT floating crafts.

The chairman appointed Capt. Izhar who has no experience in operating and handling of dredgers because it is highly technical responsibility and an inexperience officer can damage 51 million Euros dredger.

According to sources the dredger ABUL tentatively out of commission three weeks back some where or after Feb 20, this year. The Karachi Port is also losing cost and time in the face of ensuing Monsoon Season.

Since Karachi Port is exposed to monsoon it may posed tough times to the It may be recalled that the KPT had commissioned its Suction Trailer Hopper Dredger "ABUL" on November 13, last year, the port procured her at a cost of 51 million Euros from the Netherlands.

The 104.4-metre-long and 20-metre-wide dredger has two 550-kilowatt In-built jet pump motors, 110 jet nozzles and two 3,100-kilowatt engines.

Dutch experts would train local workers in operating ABUL for a year under a contract.

Trailer Suction Hopper Dredger Procurement initiated 2004 Contract awarded: M/s IHC Holland Keel laying: 16 June 2006 Delivery: Dec 2007 Cost "50.73 million.


A self propelled ship which fills its hold or hopper during dredging, while following a pre-set track. The hopper can be emptied by o bottom doors or valves (dumping) or by pumping its load ashore. This kind of dredger is mainly used in open water: rivers, canals, estuaries and the open sea.

Trailing suction hopper dredgers, commonly known simply as "hoppers" or "trailers", have a hull in the shape of a conventional ship, and are both highly seaworthy and able to operate without any form of mooring or spud. They are equipped with either single or twin (one on each side) trailing suction pipes. Material is lifted through the trailing pipes by one or more pumps and discharged into a hopper contained within the hull of the dredger. The measure of size of a hopper or trailer dredger is the hopper capacity. This may range from a few hundred cubic metres to over 20000 m" - increasingly larger vessels have been constructed in recent years to allow economic transport of the dredged material, especially for reclamation projects.

The suction pipe terminates in a drag head, which may be of the plain type or may incorporate a water jet system, blades or teeth, or other means of dislodging compacted material. The function of the drag head is to allow the material to flow to the suction inlet as efficiently as possible.

A trailing suction hopper dredger operates very much like a floating vacuum cleaner. It sails slowly over the area to be dredged filling its hopper as it proceeds. On completion of loading the dredger sails to the disposal site where the cargo can be discharged, either by opening the doors or valves in the hopper bottom, by using the dredging pump to deliver to a shore pipeline, or directly to shore by using a special bow jet. This last technique is known as rain bowing and is commonly used for reclamation and beach nourishment.

Some trailer dredgers split over their entire length to achieve a rapid discharge of material which may be difficult to discharge through doors. Such special vessels are understandably more expensive to build than those with a rigid hull.

Trailing suction hopper dredgers operate best by skimming off layers of material in long runs, such as might be found in channel dredging. They are unable to get into corners and may be difficult to maneuver in confined spaces close to quays and jetties. They are not very effective on hard materials such as the stiffer clays, but can dredge rock which has been blasted, or loosened by a cutter dredger. These dredgers are very efficient for the materials they can handle effectively. Most harbor maintenance dredging today is carried out by trailers, and they are also employed for capital projects, pipe trenching and reclamation.