The Art of Dredging

Dredging and shipping

Dredging - the past two decades


I’ve been employed in dredging for two decades.

Things have changed a lot since 1988.

This is how I’ve seen it change all:






In the last two decades dredging became a global business, and is still in full expansion.


Around 1980, there existed some twenty smaller dredging companies in Belgium and the Netherlands.


Through a process of consolidation and acquisition, they melted in the four mayors of today: “DEME“ and “Jan De Nul” from Belgium, “Boskalis” and “Van Oord” from the Netherlands.


Within “Van Oord” en “Boskalis” can still be found the remains of many Dutch dredging companies from yesteryear: HAM, Ballast-Nedam, Blankevoort, Zanen-Verstoep, Volker-Stevin, etc…


The only exception here is the Belgian company Jan De Nul, who never joined forces with other companies, but achieved growth from within.


At the sideline are some smaller Asian players; Hyundai from South Korea, Toa from Japan, and some companies operating only on a national scale. These companies mostly do not have dredging as their core business, nor are they very successful outside their own region (Far East).


They are hardly a threat in the global market, and they are definitely not in the game as main contractors for the large or complex dredging jobs in the Middle East or in the offshore market.


CSD Leonardo Da Vinci and TSHD Gerardus Mercator during joint operations in Vostochny, Russian Federation



The U.S. dredging market is a firmly protected affair; only U.S. built ships are allowed to dredge U.S. soil.

Dredging in the U.S.A. is a matter of national security and is under control of  the United States Army Corps of Engineers (U.S.A.C.E. - a department within the U.S. Army).


This has led to a complete lack of dynamism in the closed U.S. dredging industry.


U.S. dredging know-how and dredging vessels are limping behind twenty years to the Dutch-Belgian dredging powerhouse.

U.S. dredging has hardly any influence outside the U.S., with the exception of "Great Lakes Dredge and Dock Company".






Right now, the Persian Gulf is the focal point for dredging.

The number of ongoing projects, and the sheer magnitude of the projects in the Gulf is stunning; never seen before in the dredging industry.


Other countries are reaching for second or first-world-status, with the need to improve infrastructure, watermanagement, exploitation of natural resources, etc…


This often involves large dredging projects; it’s a booming market.

Think Malaysia, Thailand, Korea, South-American countries, Panama, Nigeria, Angola, India, the European periphery,etc…


India is facing giant expansion, but their national dredging industry is not able to handle the high volume of work, forcing India to source from the free dredging market.


Mainland China tries to serve its own internal dredging market, and is more and more successful at it, with the typically Chinese attitude of copying and improving foreign dredging equipment.


TSHD "Tong Tan", bought by a mainland China dredging company. Buy one, copy more.



The U.S. and Europe are saturated with maritime infrastructure, but growth is still sublimated in new projects.


The “Maasvlakte II” project is an example, together with major projects in Valencia, Marseille, London, etc...






The shipyard of choice for dredging equipment has always been the Dutch IHC-group. In a niche market, they are unchallenged world leader.

They are surrounded by a cluster of specialized suppliers to the dredging industry: Bakker-Sliedrecht, Van der Graaff, Damen, De Groot-Nijkerk, etc…


Jan De Nul has ventured outside this box  by acquiring sufficient in-house dredging technology, designing dredgers themselves, and building dredgers on “ordinary” shipyards in Korea, Croatia, China and Spain, at lower cost.


Dredging has been a cyclic business from the sixties to the eighties, with ups and downs along the road.


Belgian and Dutch dredgers were occupied in their own low-lying countries by the sea, deepening and maintaining the access to their ports.


At the end of the eighties, activity increased in the Far East, especially in the British crown colony Hong Kong, with large infrastructural projects, container-terminals, land-winning for real estate development, and the so-called “contract of the century”: the platform for the new Chep Lap Kok airport, a first + 200 million cubic meters project.

Dredging activity was triggered with the finding of easily accesible marine sand deposits.

Hong Kong kept the entire world top-20 of dredgers occupied for several years.


The crown colony was in a dredging frenzy, and dredging was the answer to every problem.

Dredging was seen as a cheap way to create valuable land.


The largest hopperdredgers of that era had a capacity of around 10.000 m3.


But dredging activity ebbed away, when Hong Kong was transferred to communist China.


Just then, Singapore was on the rise.


Starting from 1997 the world dredging fleet gathered in the island state, making a new airport (Changi), making new land for the Singaporean industry (Jurong, Tuas), container-terminals (Pasir Panjang, …), real estate (Pulau Tekong, Pulau Ubin, …), and even the beach at Sentosa.


The sky was the limit once more, with the Tuas project topping the scales at + 700 million m3.


Dredging companies reacted to the demand by developing a new size of hopper-dredgers, the so called “jumbo’s” with capacities around 24.000 m3, ships mainly built for sand-winning.


Singapore stumbled into political disputes with the neighbouring countries (Malaysia and Indonesia) on the supply of sand.

Malaysia and Indonesia decided to close down the mining of sand in their territorial seas, and all Singapore projects came to an almost standstill.

Singapore has few sand deposits within their boundaries, and these are used to finish priority projects today.

Various solutions to the shortage of sand have been tried; bringing in sand from Vietnam (with refitted bulkcarriers), mixing clay and cement, to use as fill, etc...


The Singapore blackout left the dredging companies with a fleet of giant ships, and no big projects at hand.


But within one year, the Middle East demand for dredging exploded.


Almost the entire world dredging fleet scrambled to the Persian Gulf, and took on projects in the oil-rich Gulf States, occupying the full capacity of the world dredging fleet.



Dubai, Abu Dhabi, Qatar, Saudi have large projects up and running now, all in the + 100-200 million m3 range.

And things are still heating up.


Thus, global dredging business has always thrived on one center of gravity only: Hong Kong and Singapore before, now the Persian Gulf.


There may have been large projects in other countries, but these were always singular affairs.


Hong Kong and Singapore had, and the Gulf have clusters of mega-projects, that attracted large parts of the global dredging business, and gave large economies of scale to clients and contractors alike.


During the Hong Kong and Singapore years, contractors often joined forces in Joint Ventures.


In the Persian Gulf, single dredging companies are handling mega-projects (+200 million m3 of sand) on their own, with little or no assistance from other dredging companies.

Handling large projects alone reflects the growth of dredging companies, since the ninieties.


The demand in the Gulf has given rise to the birth of “mega” dredgers.


TSHD “Vasco Da Gama” (JDN) was the early bird in this categorie, at 33.000 m3, launched in the year 2000.



By 2009, two ships with a hopper capacity of 46.000 m3 will follow, for the Belgian company Jan De Nul. DEME plans two ships of 33.000 m3, and Van Oord has plans in the + 40.000 m3 range.






In dredging; ships with specialized capabilities have always created their own market.


  1. Trailing hopper dredgers with a deepdredge installation can dredge up to 150 meters deep. They have find employment in the offshore industry, or for sandwinning, where no other options are available. 
  2. Heavy duty cutterdredgers have made their mark since the eighties, often seagoing, and with rock-cutting capabilities.

 CSD JFJ De Nul, with special features for seagoing jobs


  1. Jumbo- and mega dredgers allow giant landfill projects in land-hungry countries.
  2. Mega-dredgers are able to transport sand long range in an economical way.
  3. Accurate positioning and new survey systems allowed a breaktrough of dredging technology in the offshore industry, mainly for trenching and backfilling. 
  4. Smaller hopper-dredgers showed a development towards low-budget, shallow draught, fuel-efficiency, less crew. They prove to be very cost effective in maintenance dredging.
  5. The development of active dragheads, and the use of more powerful equipment allowed trailer dredgers to dredge more cohesive soils,  breaking into cutter dredger territory.




The sheer volume of work today, the booming demand in the dredging market, the ongoing newbuilding of larger, ever more efficient dredgers and the opening of new markets give a healthy perspective to the dredging industry for the next decade.


Consolidation and mergers have giving dredging companies global clout.



Marc Van de Velde




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