number 104 | september 2006 - iadc dredging · jan vandenbroeck flexibility and ingenuity were...

TERRAETAQUAMaritime Solutions for a Changing World

Number 104 | September 2006

MEMBERSHIP LIST IADC 2006Through their regional branches or through representatives, members of IADC operate directly at all locations worldwide

AFRICADredging and Reclamation (Jan De Nul) Ltd, Lagos, NigeriaDredging International Services Nigeria Ltd, Ikoyi Lagos, NigeriaNigerian Westminster Dredging and Marine Ltd., Lagos, NigeriaVan Oord Nigeria Ltd, Ikeja-Lagos, NigeriaBoskalis South Africa, Pretoria, South AfricaDredging International - Tunisia Branch, Tunis, Tunisia

ASIABoskalis Westminster International bv, Beijing, P.R. ChinaBoskalis Westminster International bv, Kowloon, Hong Kong, P.R. China Far East Dredging (Taiwan) Ltd, Taipei, Taiwan ROCFar East Dredging Ltd. Hong Kong, P.R. ChinaPenta-Ocean Construction (Hong Kong) Ltd., Hong Kong, P.R. ChinaVan Oord ACZ Marine Contractors bv Hong Kong Branch, Hong Kong, P.R. ChinaVan Oord ACZ Marine Contractors bv Shanghai Branch, Shanghai, P.R. ChinaBallast Ham Dredging India Private Ltd., Mumbai, IndiaBoskalis Dredging India Pvt Ltd., Mumbai, IndiaVan Oord ACZ India Pte Ltd, New Delhi, IndiaP.T. Boskalis International Indonesia, Jakarta, IndonesiaPT Penkonindo LLC, Jakarta, IndonesiaPenta-Ocean Construction Co. Ltd., Tokyo, JapanTOA Corporation, Tokyo, JapanBoskalis Westminster International bv Korea Branch, Seoul, KoreaHyundai Engineering & Construction Co. Ltd., Seoul, KoreaVan Oord Dredging and Marine Contractors bv Korea Branch, Busan, KoreaBallast Ham Dredging (Malaysia) Sdn Bhd, Johor Darul Takzim, MalaysiaBoskalis Westminster International bv, Kuala Lumpur, MalaysiaPenta-Ocean Construction (Malaysia) Sdn. Bhd., MalaysiaTideway DI Sdn Bhd, Kuala Lumpur, MalaysiaVan Oord (Malaysia) Sdn Bhd, Selangor, MalaysiaBoskalis Westminster International bv, Manilla, PhilippinesVan Oord Dredging and Marine Contractors bv Philippines Branch, Manilla, PhilippinesBoskalis International Pte Ltd., SingaporeDredging International Asia Pacific (Pte) Ltd., SingaporeJan De Nul (Singapore) Pte. Ltd., SingaporeVan Oord Dredging and Marine Contractors bv Singapore Branch, SingaporeSiam Goyo Co. Ltd., Bangkok, Thailand

AUSTRALIABoskalis Australia Pty, Ltd., Sydney, AustraliaDredeco Pty. Ltd., Brisbane, QLD, AustraliaVan Oord Australia Pty Ltd., Brisbane, QLD, AustraliaWA Shell Sands Pty Ltd, Perth, AustraliaNZ Dredging & General Works Ltd, Maunganui, New Zealand

EUROPEDEME Building Materials NV (DBM), Zwijndrecht, BelgiumDredging International N.V., Zwijndrecht, BelgiumInternational Seaport Private Ltd, Zwijndrecht, BelgiumJan De Nul Dredging nv, Aalst, BelgiumJan De Nul nv, Aalst, BelgiumN.V. Baggerwerken Decloedt & Zoon, Oostende, BelgiumBoskalis Westminster Dredging & Contracting Ltd., CyprusVan Oord Middle East Ltd, Nicosia, CyprusTerramare Eesti OU, Tallinn, EstoniaTerramare Oy, Helsinki, FinlandAtlantique Dragage S.A., Nanterre, FranceAtlantique Dragage Sarl, Paris, FranceSociété de Dragage International ‘SDI’ SA, Lambersart, FranceSodranord SARL, Le Blanc-Mesnil Cédex, FranceBrewaba Wasserbaugesellschaft Bremen mbH, Bremen, GermanyHeinrich Hirdes G.m.b.H., Hamburg, GermanyNordsee Nassbagger-und Tiefbau GmbH, Wilhelmshaven, Germany

Irish Dredging Company, Cork, IrelandVan Oord Ireland Ltd, Dublin, IrelandBoskalis Italia, Rome, ItalyDravo SA, Italia, Amelia (TR), ItalySocieta Italiana Dragaggi SpA ‘SIDRA’, Rome, ItalyBaltic Marine Contractors SIA, Riga, LatviaEuropean Dredging Company S.A, Steinfort, LuxembourgTOA (LUX) S.A., Luxembourg, LuxembourgAannemingsbedrijf L. Paans & Zonen, Gorinchem, NetherlandsBaggermaatschappij Boskalis B.V., Papendrecht, NetherlandsBallast Nedam Baggeren bv, Rotterdam, NetherlandsBoskalis B.V., Rotterdam, NetherlandsBoskalis International B.V., Papendrecht, NetherlandsBoskalis Offshore bv, Papendrecht, NetherlandsDredging and Contracting Rotterdam B.V., Bergen op Zoom, NetherlandsHam Dredging Contractors bv, Rotterdam, NetherlandsMijnster zand- en grinthandel bv, Gorinchem, NetherlandsTideway B.V., Breda, NetherlandsVan Oord ACZ Marine Contractors bv, Rotterdam, NetherlandsVan Oord Nederland bv, Gorinchem, NetherlandsVan Oord nv, Rotterdam, NetherlandsVan Oord Offshore bv, Gorinchem, NetherlandsVan Oord Overseas bv, Gorinchem, NetherlandsWater Injection Dredging bv, Rotterdam, NetherlandsDragapor Dragagens de Portugal S.A., Alcochete, PortugalDravo SA, Lisbon, PortugalBaggerwerken Decloedt en Zoon NV, St. Petersburg, RussiaBallast Ham Dredging, St. Petersburg, RussiaDRACE, Madrid, SpainDravo SA, Madrid, SpainSociedade Española de Dragados S.A., Madrid, SpainBoskalis Sweden AB, Gothenburg, SwedenVan Oord Sweden ab, Gothenburg, SwedenDredging International (UK) Ltd., Weybridge, UKJan De Nul (U.K.) Ltd., Ascot, UKRock Fall Company Ltd, Aberdeen, UKVan Oord UK Ltd., Newbury, UKWestminster Dredging Co. Ltd., Fareham, UK

MIDDLE EASTBoskalis Westminster M.E. Ltd., Abu Dhabi, UAEGulf Cobla (Limited Liability Company), Dubai, UAEJan De Nul Dredging Ltd. (Dubai Branch), Dubai, UAEJan De Nul Dredging, Abu Dhabi, UAEVan Oord Gulf FZE, Dubai, UAEBoskalis Westminster Middle East Ltd., Manama, BahrainBoskalis Westminster (Oman) LLC, Muscat, OmanBoskalis Westminster Middle East, Doha, QatarBoskalis Westminster Al Rushaid Co. Ltd., Al Khobar, Saudi ArabiaHAM Saudi Arabia Company Ltd, Damman, Saudi Arabia

THE AMERICASCompanía Sud Americana de Dragados SA, Capital Federal, ArgentinaVan Oord ACZ Marine Contractors bv Argentina Branch, Buenos Aires, ArgentinaBallast Ham Dredging do Brazil Ltda, Rio de Janeiro, BrazilVan Oord Curaçao nv, Willemstad, CuraçaoDragamex SA de CV, Coatzacoalcos, MexicoDredging International Mexico SA de CV, Veracruz, MexicoMexicana de Dragados SA de CV, Col. Polanco, MexicoCoastal and Inland Marine Services Inc., Bethania, PanamaStuyvesant Dredging Company, Louisiana, USABoskalis International Uruguay S.A., Montevideo, UruguayDravensa C.A., Caracas, VenezuelaDredging International NV - Sucursal Venezuela, Caracas, Venezuela

Terra et Aqua is published quarterly by the IADC, The International Association of

Dredging Companies. The journal is available on request to individuals or organisations

with a professional interest in dredging and maritime infrastructure projects including

the development of ports and waterways, coastal protection, land reclamation,

offshore works, environmental remediation and habitat restoration. The name Terra et

Aqua is a registered trademark.

© 2006 IADC, The Netherlands

All rights reserved. Electronic storage, reprinting or abstracting of the contents is

allowed for non-commercial purposes with permission of the publisher.

ISSN 0376-6411

Typesetting and printing by Opmeer Drukkerij bv, The Hague, The Netherlands.

Contents 1

EDITORIAL 2

IMPACT OF EUROPEAN UNION ENVIRONMENTAL LAW ON DREDGING 3FREDERIK MINK, WOUTER DIRKS, GERARD VAN RAALTE,HUGO DE VLIEGER AND MARK RUSSELLEU environmental law and international conventions are not always compatible.The European Dredging Association makes its case on when and why dredged material should not be considered waste.

TOXICITY ASSESSMENTS FOR DREDGED MATERIAL CHARACTERISATION 11IN PORTS AFFECTED BY METALLIC POLLUTIONM. CARMEN CASADO MARTINEZAt the ports of Cartagena and Huelva, Spain dredged materials are affected by mining activities and require careful examination to aid decision making about disposal, as described by the IADC Award winner at the PIANC Conference in Portugal in May.

IMO/UNEP/SOA WORKSHOP ON MARINE POLLUTION PREVENTION 20AND ENVIRONMENTAL MANAGEMENTNEVILLE BURTAs part of an ongoing effort to encourage training and discussion ofdredging related issues, the IADC/CEDA Environmental Seminar waspresented at Dalian, China in late May to delegates from 14 countries.

PORT 2000, LE HAVRE’S NEW CONTAINER TERMINAL: BREAKWATERS 22AND DREDGING OF THE NAUTICAL ACCESS CHANNELJAN VANDENBROECKFlexibility and ingenuity were required to meet the environmental andeconomic demands for expanding France’s largest port which faces therough swells of the Channel.

BOOKS/PERIODICALS REVIEWED 28Two new books, Dredging in Coastal Waters and Die Küste, examine policies, methods and solutions to dredging in coastal waters around the world.

SEMINARS/CONFERENCES/EVENTS 32A renewed Call for Papers for the upcoming WODCON and three newseminars co-organised by IADC are noteworthy.

CONTENTS

TERRAETAQUA

EDITORIAL

Clean water is a prime resource for life. The concerns of the world as a whole about the marineenvironment are concerns deeply shared by the dredging and maritime construction industry. During the multitude of projects which are dependent on the services of dredging, like portexpansion and offshore development, environmental impact assessments and remediation operations are prerequisites and they are built into the project planning. In this way the dredgingindustry strives to comply with international and national guidelines.

Often these rules and conventions, laws and treaties have been developed for general regulation ofwaterways, rivers and oceans and they do not directly define dredging activities. Yet they do affecthow the dredging industry conducts its operations. For instance, the London Convention of theInternational Maritime Organisation (IMO) and certain European Union Directives have a direct impacton the dredging industry, though the word dredging is not necessarily apparent. Sometimes theseregulations result in stimulating R&D for new techniques or in the invention of new equipment.Sometimes they result in costly delays of projects. The need for awareness about current thinking onthe issues of disposal, remediation and environmentally sound dredging is of paramount importanceand requires a professional approach.

In this issue, Terra considers environmental subjects from a variety of angles. First, the similarities – and differences – between international treaties and European environmental law are examinedwith the core question, “what is the definition of waste?” being tackled. In addition, a report on arecent environmental workshop organised under the auspices of the IMO and the United NationsEnvironmental Programme (UNEP) in China demonstrates the positive effects of cooperation amongstinternational organisations.And then ports both old and new are profiled. The IADC Award presented to a young author atPIANC’s May meeting in Portugal explains the intense attention spent to the remediation of Spain’sports from pollution caused by the mining industry. Finally, the story is told of France’s newlyexpanded Port 2000 at Le Havre with its necessary environmental accommodations such as creatingnew beaches and re-use of dredged material.

As the global economy increasingly demands new maritime infrastructure, the role of the dredgingindustry on the world stage becomes more and more significant. Maritime infrastructure is essentialfor the world’s economic motor. Defining with clarity an economic and environmental framework andfinding a good balance for sustainable development of the global infrastructure in and around coastalareas and inland waterways will contribute to the world. To both the improvement of the welfare ofmankind and to the preservation of the environment for future generations.

Robert van GelderPresident, IADC Board of Directors

2 Terra et Aqua | Number 104 | September 2006

IMPACT OF EUROPEAN UNIONENVIRONMENTAL LAW ON DREDGING

FREDERIK MINK, WOUTER DIRKS, GERARD VAN RAALTE, HUGO DE VLIEGER AND MARK RUSSELL

ABSTRACT

In certain aspects of environmental lawthere is a potential friction between EUDirectives and international conventions. In these cases, international conventionshave priority over EU law because theyconstitute treaties between sovereignnations. Thus when the question arises, “Is dredged material waste or not?”, the answer may not always be the same.The European Commission has consistentlyargued that dredged material is a form of“waste” since the holder attempts to getrid of it. The industry, as represented by theEuropean Dredging Association, maintainsthat dredged material is foremost a naturalresource that should be kept in itsenvironmental compartment. Since thisdifference is apparently a long way frombeing resolved, another question arises:Can the dredging community live with theEU waste hierarchy principles as such?

The answer as far as the waste hierarchy isconcerned is a mitigated “yes, providedthat the national authorities understand theissue”. Moreover, for marine waters wherethe bulk of dredging takes place anyway,the framework established under theumbrella of the London Convention has

priority over EU law and is also morehelpful to the sector. Other Directives onenvironmental protection, in particular theHabitats and Birds Directives, causeadministrative nightmares and lead todelays or cancellation of projects and toincreased costs.

INTRODUCTION

The European Dredging Contractorsestablished the European DredgingAssociation (EuDA) in 1994 as a tradeassociation for contacts with Europeaninstitutions; this includes influencing andtracking EU law that might impact thedredging sector. Amongst the areas where EU legislation affects the industry,environmental law has taken a prominentrole. The EuDA Environment Committeehas recently prepared a comprehensivereview of European environmental rulesand their impact on the practice ofdredging and dredged material disposal.This article presents a summary of thefindings.

ON INTERNATIONAL LAW

The European Union is formed by acommunity of nations that have agreed byTreaty to transfer legislative and executivecompetences in a number of domains to a supranational level. Environmental law is an area where EU competences are farreaching because it was recognised early onthat environmental problems and pressuresdo not stop at national borders, but are feltcommunity wide.

EU law is in essence built on three types ofinstruments:• Framework Directives (the term of

Directive is equivalent to a law in nationallegislation) define a general approachwhich sets a number of boundaryconditions and constraints and have to be implemented by each member state in accordance with its specificcircumstances. Certain provisions of aFramework Directive may also be detailedin a later stage at the European level andmade effective by other legal instruments.When the instrument of a Directive isused in such a case, one speaks of aDaughter Directive.

• Directives are equivalent to laws and arebinding on the member states, except for

Above, Beach replenishment along the Dutch coast

where water, sand and birds intermingle and EU

Directives on Birds and Habitats pertain.

Impact of European Union Environmental Law on Dredging 3


the fact that they first have to be“transposed” into national law. This poses a particular problem: Some member states have a tendency to transpose (environmental) EU law in a very strict and stringent manner,while others tend to follow the minimumrequirements of the Directive.

• Regulations are legal decisions taken at EU level that are binding as such forthe member states and do not needtransposition. They usually concern moretechnical details on which there is nomajor disagreement.

It may be clear that the EU law has thepotential to deeply influence nationallegislation; also clear is that the resultinghierarchy of rules and regulations isanything but simple, while the transpositionmechanism often results in the oppositeeffect of what was intended: In severalcases transposition creates importantdifferences in national law. Moreover, theimpact of a particular EU law frequently hasto be tested before the Court of Justice inorder to assess its judicial limits.

The next question to be raised is: how doInternational Conventions and Treatiesrelate to EU law and to national law?

International Conventions, such as theLondon Convention which was establishedunder the umbrella of the IMO, but alsothe Oslo-Paris (OSPAR) Convention for theAtlantic and the North Sea, are agreementsbetween sovereign nations; each nationdecides independently whether or not toratify a particular Convention. When acertain number of countries have ratified aConvention, it can become international

law. As the ratification is done by sovereignstates, the EU as a supranational body doesnot play a role. Consequently, InternationalConventions have priority over EU law. As will become evident, this may lead to friction between the rules at theinternational and supranational levels.

Figure 1 illustrates the situation and listsalso a number of advisory bodies and/orguidance documents that are helpful, but are not legally binding.

EU law and dredged materialEU law does not deal specifically withdredged material, nor is there any intent to do so. Nevertheless, a number of EUDirectives have an impact on themanagement of dredged material, eitherdirectly or indirectly. Figure 2 presents anoverview of the structure of the relevantregulations and the relationship betweenthe various Directives.

The conclusion is that relevant rules can be grouped under the three headings ofwaste, water and habitat protection. Of these three, the Waste FrameworkDirective and related Directives occupy themost discussion time, since a great dealdepends upon defining what constituteswaste and, subsequently, on the limits ofcompetence of the regional seasconventions versus EU law.

Figure 1. Hierarchy of legislation.

Fram

ewo

rk

Dau

gh

ters

Draft Under revision

Agriculture Industry

E U

LE

GIS

LA

TIO

N

NA

TIO

NA

L

CO

NV

EN

TIO

NS

Un

der

um

bre

lla

WATER FRAMEWORK DIRECTIVE 2000/60/EC

WASTE FRAMEWORK DIR. 75/442/EEC +

91/156/EEC

GROUND WATER

80/68/ EEC

VARIOUS WATER

QUALITY

SHIPMENT 2006/xx/EEC

LANDFILL 99/31/EC

WILD BIRDS 79/409/EEC

HABITAT DIRECTIVE 92/43/EEC

HAZARDOUS WASTE

91/689/EEC

MINING+ EXTRACTION 2006/xx/EC

SEWAGE SLUDGE

86/278/EEC

Ramsar Convention for Wetlands

Basel Convention on export of

Hazardous Waste

London, OSPAR, Helcom, Barcelona Conventions

Under revision

NITRATES DIR. 91/676/EEC

INT. POLL. PREVENTION

CONTROL 96/61/EC

Under revision

Figure 2. Overview of the structure of the relevant regulations and the relationship between the various Directives.


WASTE FRAMEWORK DIRECTIVE

The Directive establishes a hierarchy, a strategy for prioritising management of “waste” as follows:a) Preventionb) Re-usec) Recycling d) Processing or recovery e) Disposal

“Waste” is defined as “any substance orobject which the holder discards or intendsto discard”. Under this very broad definitionthe European Commission has consistentlyargued that dredged material is a form of“waste” since the holder attempts to getrid of it. So far this discussion has not beenvery fruitful: The industry as represented bythe EuDA maintains that dredged materialis foremost a natural resource that shouldbe kept in its environmental compartmentand that this does not in itself cause thematerial to become a form of waste.

FREDERIK MINK

joined Interel in 2005 as a Senior

Consultant with a focus on transport,

energy and environment. For 10 years he

was secretary-general of the European

Dredging Association (EuDA). Prior to

this he worked for over 20 years for

Westinghouse Corporation’s nuclear

division.

Basically, it is difficult to understand why amaterial that can be “re-used” in the sameapplication as where it was found should becalled waste in the first place (see Box for acase study).

As a clear definition apparently has not yetbeen found, the question becomes: Can thedredging community live with the EU wastehierarchy principles as such? With this inmind the EuDA Environment Committeehas developed an approach in the form ofa decision logic diagram in line with theestablished “waste” hierarchy. A distinctionbetween marine water and fresh waterdredging has also been made since theconstraints are somewhat different. These distinctions are presented in Figures 3and 4. In both cases the logic sequence ofthe waste hierarchy is followed.

Marine water dredgingThe fact that the regional sea conventionsdefine their own limits of jurisdiction was

WOUTER DIRKS

graduated in 1990 from Technical

University Delft, the Netherlands. He then

joined Ballast Nedam working on inter-

national construction projects. Since

1995 he has worked in the dredging

industry and is now employed by Van

Oord where he is now lead engineer

environmental issues. He is chairman of

the Environment Committee of EuDA.

GERARD VAN RAALTE

graduated in 1976 with a MSc in civil

engineering from Technical University

Delft, the Netherlands. After working at

GeoDelft and Breejenbout, he joined

Boskalis’ in-house engineering department

Hydronamic in 1986 where he is now a

Project Engineer. He is a member of both

the EuDA Environment Committee and

CEDA Environmental Steering Committee.

HUGO DE VLIEGER

joined the Belgian-based DEME Group

in 1973, where he presently fulfils a

number of top-level functions: Chairman

of the Board, DEC NV; General Manager,

Baggerwerken Decloedt & Zoon;

Managing Director, CVBA Fasiver and

NV Silvanmo; and Chairman, Management

Committee De Vries & van de Wiel BV.

EU Stratery

Pre

ven

tio

n

NEED FOR DREDGING?

Re-use

Dis

po

sal

CONFINED DISPOSAL

Processing

Relocation at selected locations

Beneficial use

Placement in environmental comp.

Treatment

Aquatic

Upland

Re-u

se

Recy

cle

<1%

N

N

Y

Y

<5%

<5%

>5%

<5%

+/- 80%

N.-B.: the annual volume of dredged material in the marine environment is estimated at 200-250 million tons/year for the EU. The % in the diagram indicates roughly the estimated breakdown.

Figure 3. Decision logic diagram for dredged material in a marine environment.

MARK RUSSELL

is Director of Marine Aggregates for

the British Marine Aggregate Producers

Association, the trade association for

the UK marine aggregate sector. He has

been involved in the industry for over

10 years, working for the largest British

producer, Hanson Aggregates Marine,

before moving to BMAPA five years ago.


carefully considered. For the OSPARConvention the limit is the tidal influence in the tributaries. Disposal of dredgedmaterial is dealt with in essence under theDredged Material Assessment Framework(DMAF) which was developed for theLondon Convention and has been reviewedin Terra et Aqua (Burt and Fletcher, nr. 66March 1997) previously. The OSPARConvention clearly has no competenceconcerning upland disposal or for beneficialuse applications outside the marinecompartment. As the Conventions acceptthe placement of dredged material backinto the marine waters, the conclusion wasdrawn that EU law has hardly any impacton the dredging process in marine andcoastal waters, except when heavilycontaminated materials are involved. Figure 3 shows the quantities and thebreakdown into categories.

At this point one faces the potential frictionbetween international law under theConventions and EU law as a supranationalbody of rules. The first question to ask

concerns the territorial limits of competenceof EU environmental law. There is nosimple, nor single answer to that question,but the Water Framework Directive (seebelow) claims jurisdiction roughly until onemile beyond the coastline. However,international law supersedes EU law andthe jurisdictional boundary of the OSPARConvention and other regional conventionsextends well inland. The EuDA EnvironmentCommittee therefore takes the positionthat for marine dredging the internationalconventions apply as implemented bynational law and EU law only may applywhen nothing is foreseen in theseconventions. Since the conventions acceptthat dredged material is put back into thewater body, unless it is too contaminated,the Environment Committee concludes thatfor dredging in marine waters current EUlaw may only be relevant to the confineddisposal of dredged material on land.

Figure 3 shows the quantities of dredgedmaterial and the assignment to thecategories in the waste hierarchy.

The conclusion is that overall some 5-10%of the dredged material may be socontaminated that it needs to be disposedof in a confined facility. At this point in thereview the question arises whether disposalsites fall under any specific EU wastelegislation and if so which ones.

The answer is that upland disposal would becovered by the so-called Landfill Directive,which introduces stringent isolationrequirements and leads to considerableexpense. Landfill sites are typically notintended for the disposal of dredgedmaterial, but in some cases there is noalternative available. In most countriesconcerned this applies only to a minutefraction of the dredged material.

So what about sub-aquatic disposal sites?These are clearly not covered by specific EUrules and must be regulated at the nationallevel. Fundamental to the assessment stated above is the consideration thatplacing dredged material back into itsenvironmental compartment is a form of re-use that is in principle beneficial for theenvironment. In fact, it is particularly helpfulin maintaining the sediment balance.

Fresh water dredgingWith respect to fresh water dredging, one must recognise that the Conventionsno longer play a role, but that the WasteFramework Directive applies. The sameapproach can be followed as for marinewaters, since in both cases the wastehierarchy is respected. The resultinginteraction with other EU legislation such as the Water Framework Directive may bestronger. In terms of the decision logic thefollowing “disposal” modes were considered:

• Beneficial use:– as fill material– as construction material– for soil improvement of agricultural land

• Relocation:Placing dredged material at specificlocations in the environmentalcompartment so that it fulfils its role inthe sediment balance.

EU Stratery

Pre

ven

tio

n

NEED FOR DREDGING?

Re-use

Dis

po

sal

CONFINED DISPOSAL

Processing

Relocation at selected locations

Beneficial use

Placement in environmental comp.

Treatment

Aquatic

Upland

Re-u

se

Recy

cle

UPLAND

AQUATIC

<30%

N

N

Y 40-50%

Y +/- 30%

Y +/- 20%

Y 10-20%

Y

N.-B.: the annual volume of dredged material in the fresh water environment is estimated at 50-60 million tons/year in the EU. The % indicates the estimated breakdown.

Figure 4. Decision logic diagram for dredged material in a fresh water environment.


• Placement:The disposal of dredged material atsuitable disposal locations.

• Processing:– separation of sand and silt– manufacturing bricks or basalt– biological treatment to reduce

contaminant level– dewatering, ripening– land farming – and more…

Direct impact of specific waste legislation isin this case limited to the Landfill Directive

Figure 5. Where does the Water Framework Directive apply? In the northern Netherlands, a branch of the Rhine, the River IJssel, carried contaminated silt into Lake Ketelmeer

where it settled into the bed. In an action to clean-up the waterway, the IJssel-oog (eye) repository was constructed for safe storage of contaminated dredged materials.

which establishes the (stringent) provisionsfor the landfill sites, but which alsorecognises that disposal of dredged materialalong waterways, on agricultural land or atsuitable subaquatic locations are acceptablesolutions, as long as contaminants remainbelow certain limits. The Landfill Directivethus provides a number of escape routesthat help to avoid disposing dredgedmaterial in landfills. Some member stateshave recognised these possibilities in theirnational rules, but others appear to focusmore on the isolation provisions for landfillsites, thus adding to the cost of dredgedmaterial disposal.

ContaminantsThe last aspect to be discussed under thisheading concerns the contaminants.

The European Commission will not set anyspecific limit values for dredged material;this is left to the member states. The onlyquantitative values that have been aroundare limits set in a separate Sewage SludgeDirective; for lack of other standards thesehave sometimes been quoted in connectionwith dredged material. However, thesevalues are currently being revised since theyare too high and they are not actuallysuitable for dredged material.


Member states have been requested underthe rules of the OSPAR Convention orequivalent, to set limit values for seadisposal of contaminated dredged material.As a consequence one can find a widerange of classification systems andthreshold values in some member states,while other countries are of the opinionthat dredged material does not lend itselfto setting limit values for individualsubstances and should be assessed on a case by case basis.

WATER FRAMEWORK DIRECTIVE

The Water Framework Directive, whichbecame European law in 2000, has as itsgoal to gradually improve the quality ofEuropean waters to some standard whichmay be called “good”. This objective is verylaudable, but the way to get there is stillvery much under discussion amongst theCommission, the member states and thestakeholders.

The question raised here is: Could thisDirective possibly be a constraint fordredging operations? In the implementation

Figure 6. Completion of the Ketelmeer clean-up led to better access to the River IJssel, which resulted in clean materials to create De Kreupel, a 70 ha bird sanctuary.

process of the Water Framework Directive(which is foreseen to last some ten years), it has been repeatedly emphasised that thislaw has a long-term goal. It is recognisedthat water quality varies considerably overtime and as a function of physicalparameters, chemical conditions, biologicaland ecological factors as well ashydromorphological boundary conditions.Obviously it is no easy task to cast such aframework into detailed implementationmeasures and therefore a series ofquestions arises:• Will there be constraints on dredging

operations in ports where the risk ofreleasing contaminants from silt cannotbe excluded?

• Is short-term deterioration of waterquality resulting from operationalinterventions and maintenance practicesan issue?

• How should one deal with the interactionbetween water and sediment?

• Can one legislate water quality withoutsetting boundary values for sediment?

• How should changes in hydromorphologyowing to infrastructure works beassessed in terms of their impact onwater quality?

Even though these questions can beconsidered reasonable, it is too early toprovide answers since the relevant RiverBasin Management strategies and theDaughter Directives are still underdevelopment. Much will depend on theconsideration of variability over time: does exceedance of established qualitystandards, e.g. for TBT, matter if the annualaverage is within the limits? How can thelegislator deal with the weak links betweenchemical quality and hydromorphology?

In the implementation process it has beenrepeatedly stated that the Directive is notintended to interfere with normaloperations and maintenance practices ofwaterways and ports. This will be translatedinto guidance for selection of sampling andmonitoring points remote from areas ofactivity and in establishing quality standardsthat recognise (some) variability in theaquatic environment.

The conclusion of this committee is thatmaintenance dredging will probably not be affected by this Directive, but thatcapital dredging may become even moreconstrained in water bodies falling under its


waters by 2021. It also claims competenceto regulate the status of the seabed and its subsoils. Currently good environmentalstatus is not defined, but by analogy to theimplementation of the Water FrameworkDirective one can assume that it will beestablished on the basis of a series ofparameters, including physical and chemicalconditions, biological and ecologicalprocesses, physiographic and geographicfactors. In the wake of such an approach it is clear that the European Commissionattempts to establish jurisdictionalcompetence over the wider marine environ-ment, where currently only internationalbodies like OSPAR and the respectivemember states are competent to regulate.

The discussion on the Marine Strategy is in anearly stage and it is expected that memberstates will be reluctant to give up their exclusive

scope. One may also foresee new businessopportunities for environmental dredging inwater bodies where historic contaminationneeds to be removed in order to meet theecological objectives (Figures 5, 6 and 7)

HABITATS AND BIRDS DIRECTIVES

These two Directives aim to protectbiodiversity and rare biotopes and species.The implementation process has led to theestablishment of an ecological network acrossEurope called Natura 2000. Natura 2000consists of designated “special areas ofconservation” under the Habitats Directiveand “special protection areas” under theBirds Directive most of which would beinterconnected via corridors or other meansof protection. Why would these Directivesimpact dredging?

The reason is that coastal ports and harboursare very often located at, near or adjacent toNatura 2000 sites. This imposes on portsmany restrictions in case they want toexpand their site area or when they wish tobuild new infrastructure. In short portdevelopment projects face severe delays andincreased costs, in particular when situated atthe mouth of estuaries. Similar observationscan be made for infrastructure developmentalong valuable stretches of coastline.

The consequences for the dredging sectorare likely to be indirect, but significant. The European dredging industry hasnoticed increasing problems with permitsfor infrastructure development in themarine environment and it faces increasingmonitoring requirements in sensitiveenvironments. A number of importantinfrastructure development projects haveeven been cancelled. Other impacts wouldentail such things as the presence ofdesignated marine sites near ports, wheredisposal is not permitted; delays ininfrastructure projects near designated sitesand problems with establishing acceptableforecasts for habitat impact studies.

Again, there are also opportunities: TheHabitats Directive foresees the possibility toprovide compensation measures if valuablenature would be threatened owing to

project development. The dredging sectorcan often be of considerable help increating new nature sites near thedevelopment area. This can take the formof artificial islands, extended beaches andberms or habitat restoration through the re-creation of mudflats and salt marshes.

MARINE STRATEGY

The European Commission published aThematic Strategy on the Protection andConservation of the Marine Environmentin October 2005 (see http://ec.europa.eu/environment/water/marine.htm). This iscurrently a document for discussion, but mayhave repercussions on dredging in a moredistant future. The strategy and the resultingproposed Directive aim to achieve “goodenvironmental status” of European marine

Figure 7. Also created from clean fill is an 800 ha nature reserve

at the mouth of the IJssel (IJsselmonding).


jurisdiction over marine zones. The followingquotes give an indication of the intentionof the European Commission on the role itwishes to play in the marine environment:• “Many of Europe’s regional seas are the

subject of international conventions anda number of these have made excellentcontributions to the marine protection.However, these conventions have fewenforcement powers and thiscompromises their effectiveness inachieving agreed goals.”

• “In order to build on progress madethrough the existing institutions, policiesand conventions and to take action tomake further progress, there is a need toformulate a clear, overarching vision forthe marine environment and associatedpolicies. A strong EU policy on marineprotection will complement and bolsterthe current patchwork of institutionalarrangements by providing a legallyenforceable framework (…).”

The impact of the Water Framework cannotyet be established in full, but it is likely to have mainly indirect effects as a result of complicating project development. Direct effects may result from additionalmonitoring requirements during projects andafter completion as imposed by the respectivepermitting authorities in member states.

The conclusion with respect to dredgingoperations in relation to the Habitats andBirds Directives is: their effects will bemainly indirect but not insignificant. The effects of this legislation can lead tosignificant delays in project approval andalso to important increases in costs causedby extended needs for impact assessment.Of particular concern to the industry is thefact that impact assessment for ecologicaleffects in marine waters may be verydifficult, since the environment is sodynamic, and thus lead to further delays in the approval process.

CONCLUSION

The conclusion of this assessment by theEuDA Environment Committee is that theimpact of EU environmental legislation onthe dredging sector is fundamental withrespect to the question of dredged materialmanagement and priorities, but is restrictedwhen it comes to detailed implementationrules. The main impact results from theLandfill Directive, but even here muchdepends on the way the member stateconcerned has transposed this piece oflegislation into national law. Especially formarine waters, where the bulk of dredgingtakes place anyway, the frameworkestablished under the umbrella of theLondon Convention has priority over EUlaw and is also more helpful for the sector.

The Marine Strategy may in the futureundermine the exclusive competence of theinternational conventions.

CASE STUDY

That the lofty definition of “waste” in EUlegislation can lead to lengthy and ratheruseless debates may be illustrated by arecent case involving the Port of LondonAuthority (PLA) and the EnglishEnvironment Agency (EA).

The PLA intends to carry out dredging inthe River Thames Prince’s Channel in viewof increasing the navigational depth and itplans to use the dredged sand to improvea nearby construction site. EA has takenthe view that the material resulting fromdredging is waste according to the WasteFramework Directive and should thereforemeet stringent requirements when it isdisposed of on land. The EA does not wishto recognise the fact that clean sand canbe used beneficially as constructionmaterial. The case was submitted to LordKingsland for a legal ruling.

The Right Honourable Lord, rather thanstating something like “don’t be silly”, or“let’s use common sense”, or even “what’s

in a name?”, had to review the case lawproduced by the European Court on theseand similar matters and based thereonproduced a long argument whichconcludes that:

1. “the dredged substance [from thePrince’s Channel] is [not waste, but] aproduct, or at least a by-product;

2. if, nevertheless [the interpretation of the Waste Framework Directive wouldconclude that] it is initially waste, then it is fully recovered when it becomesphysically identifiable as a product (….)once it is in the hopper of the dredger”.

The reader will notice that in the legal senseit makes significant difference at which stepin the waste hierarchy one finds oneself.Lord Kingsland draws the conclusion that,once dredged material is targeted for re-use,recycle or recovery, it is no longer waste, or ithas never been waste in the first place.These conclusions are in fact based on a verystrict reading of the definition (“Waste is any

substance or object which the producer orthe person in possession of it discards orintends to discard”.). The interpretation thushinges on the meaning attributed to“discard”. Lord Kingsland, after a lengthyreview of the jurisprudence, concludes that,as long as the holder of the material intendsto re-use or recycle, it never becomes wasteon the way; if the material is intended to berecovered there is some leeway for inter-pretation. Lord Kingsland is of the opinionthat it still does not become waste, but evenif it is considered to become waste, the partthat is recovered turns into a “product” or a “by-product” and is no longer waste.

Only material that the holder explicitlyintends to discard, or is forced to discard, isthus “waste” under the definition. A longargument is probably not necessary toconclude that this kind of reasoning is sosubtle and sophisticated that the dredgingcontractor no longer feels at ease. Nor forthat matter does the European DredgingAssociation.

TOXICITY ASSESSMENTS FOR DREDGEDMATERIAL CHARACTERISATION IN PORTSAFFECTED BY METALLIC POLLUTION

M. CARMEN CASADO MARTÍNEZ

ABSTRACT

Surface sediments from two ports affectedby mining activities (Cartagena and Huelva)were characterised following the traditionalphysicochemical characterisation based oncontaminant concentrations together withlaboratory toxicity tests. The toxicity testsincluded acute and chronic methodologiesboth on the whole sediment and on thesediment elutriates. As expected, sedimentsreported remarkable concentrations ofmetals, some failing the higher limit valuesfor open-water disposal, and organiccontamination in some areas affected byindustrial and shipping activities.

The toxicity assessment results showeddifferences amongst the two studied zones:the port of Huelva reported significanttoxicities both for the whole sediment andthe elutriate tests, while the sedimentsfrom the port of Cartagena reportedsignificant toxicity only for some wholesediment bioassays. These sedimentsprovoked little or no adverse effects forother benthic species and similar responsesto controls for elutriate tests. These resultsshow that SQGs are not always a goodpredictor for sediment toxicity, especially for evaluating the risks of elutriate waters.

In this sense the advantages anddisadvantages of laboratory toxicity testsfor dredged material characterisation andits use in ecological risk assessment fordecision-making is further discussed.

The author would like to thank Jesús M. Forjaand T. Ángel DelValls, both of the Universityof Cádiz, Spain for their contributions andsupport. The paper received the IADC Awardat the PIANC Conference in Estoril, Portugaland first appeared in the Proceedings. It isreprinted here in a slightly revised formwith permission.

INTRODUCTION

During the last decades a number ofinternational conventions on marineenvironmental protection have encouragedimpact assessment to evaluate potentialeffects on human health, living resources,amenities and other legitimate uses of thesea owing to dredged material disposal(Burt and Hayes, 2005). Even though thegreater proportion of dredged materials is similar in environmental terms to the

sediments that are present naturally, a smallproportion of sediments is contaminatedand may represent a real threat.

The extent of sediment contamination islargely influenced by operations carried out in ports and waterways, such aspassenger traffic, freight shipping,“accidental” spills or “intentional”discharges occurring close to navigationalroutes. Point source control measures havesignificantly contributed to reducingsediment contamination in recent years.Nonetheless short and long-term sources,as the result of past and present activities,may have contributed critically toworsening the environmental quality of litoral ecosystems.

The anthropogenic substancesaccumulating in aquatic systems can bedistinguished into two groups: nutrientsand pollutants (Goossens and Zwolsman,1996). Amongst other substances, metals,metalloids, oil and grease, hydrocarbonsand pesticides are pollutants traditionallyfound in ports and waterways, though theextent of environmental pollution dependson the nature of the activities performed,the characteristics of the area and thecontrol measures adopted.

Above, Figure 1. Fisheye photo of the port of Cartagena

with yacht and freight harbours visible.

Toxicity Assessments for Dredged Material Characterisation in Ports Affected by Metallic Pollution 11


A great proportion of dredged materialshas to be disposed of into the same aquatic system for economical, technical orlogistical reasons. This management optionis considered if sea disposal is identified asthe least detrimental option according tothe characterisation of the sediments to bedredged and after completing the dredgedmaterial management framework.

One of the clearest dredged materialassessment frameworks was presented byBurt and Hayes (2005) and the subject ofpre-dredging investigations for materialscharacterisation to evaluate the environ-mental aspects of dredging operations have been addressed in several guides and recommendations set up by differentgroups of experts, such as the one from the IADC-CEDA series on environmentalaspects of dredging (Peddicord and Dillon,1997) or the one recently published byPIANC (2006). These guides seek to leadthe reader through a “highly focussed,cost-effective evaluation of the potentialenvironmental impacts of dredgingoperations” that can be summarised in four steps (Peddicord and Dillon, 1997):Step 1: Project planning, including the

nature and scope of the activities,the potential dredged materialplacement options and theregulatory requirements.

Step 2: Initial evaluation, where availabledata is examined, may lead to theconclusion that no further pre-dredging evaluations are neededis gathered if needed, oneproceeds to Step 3.

Step 3: Physical, chemical and biologicalcharacterisations of dredgedmaterial.

Step 4: Interpretation of results of thedata assembled and evaluated.

This study looks at the methodologies andendpoint measurements involved duringdredged material characterisation inrelation to environmental risk assessmentand dredged material management frame-works. Specifically the use of biologicaltests in the context of navigationaldredging is addressed in two case studiesconsisting of sediments from two areaswith known metallic contamination.

An integrated approach, designed to meetthe international recommendations on theapplication of biological tests for dredgedmaterial characterisation and management(PIANC, 2006), has been used to characteriseharbour sediments and the results arepresented to study the uncertainties on theuse of the different methodologies involvedand to improve confidence in decision-makingas gaining experience and knowledge.

Nonetheless the results cannot address the questions related to the project itself(Steps 1 and 2) because of its hypotheticalnature. This study is part of the researchdeveloped at the University of Cádiz for the implementation of an integratedapproach including biological endpoints for dredged material characterisation inSpain (DelValls et al., 2001; 2003).

STUDY AREAS

The ports included in this study are locatedin areas affected by important miningactivities: the port of Cartagena and theport of Huelva (Figures 1, 2 and 3).

CartagenaThe port of Cartagena is located close tothe city of the same name on the southeastcoast of Spain. The city of Cartagena hasbeen under the influence of an abandonedlead-zinc (Pb-Zn) mining district, whichoriginates date back to the Roman Empire.

This region became one of the mostrepresentative open cast mining areas inSpain after the middle 20th century that ledto an intensive movement of metals thatultimate entered the aquatic environmentthrough direct and indirect deposition. The ore vein was mainly composed of

Figure 2. The port of Huelva with freight ships at the loading docks.

galena (PbS) and sphalerite (ZnS) with otherminor elements such as nickel (Ni) andcadmium (Cd) (Marguí et al., 2004).Furthermore the city experienced someindustrial development during the 1960sand nowadays there are several chemicaland metallurgical factories located in thesurroundings of the harbour facilities – anelectrolytic Zn plant, different fertiliser plants,a Pb smelter closed since March 1992, a fertiliser plant closed since 1993, a powerplant, an oil refinery and a shipyard.

HuelvaThe other area under study is the port ofHuelva, located in the South Atlantic coastof Spain. The Ría of Huelva comprises theestuary of the rivers Tinto and Odiel, whichform the Padre Santo Channel (Figure 3).The area delimitated by these two rivers ischaracterised by important mining andmetallurgical activities dating back threethousand years and based on pyrite (FeS2)and other sulphuric minerals. This estuarysuffered from continuous metal dischargesover centuries through acid mine drainageand solid wastes, which represent animportant long-term contamination source.

Three industrial areas are present in theTinto and Odiel catchment areas: the firstone upstream in the Tinto River, a secondone located in the Odiel River before it

joints the Tinto, and a third one just afterthis confluence. These areas include acellulose factory in the Tinto Rivercatchment area, which produces highquantities of pyrite ashes, differentphosphates and fertilisers plants, a copperand sulphuric acid factory and a powerplant, a petrol refinery and differentchemical plants are located in the leftmargin of the channel.

APPROACH

Sediment samplingThe sediment samples were collected inApril 2003 with a 0.025 m2 Van Veen grab from approximately the top 20 cm. On arrival to the laboratory, sediments werehomogenised and stored at 4ºC anddarkness prior to analysis. For each studyarea, CEDEX and the University of Cádizselected four sampling stations (Figure 3).As Figure 3 shows, two inner stations wereselected in Cartagena, one on the east (C1)and a second one in the western bay (C2).The other two stations were located on the east and west external part of the bay(C3 and C4, respectively).

In Huelva four different stations weresampled and numbered going seawardalong the estuary.


IADC AWARD PRESENTEDAT 31st PIANC CONFERENCEIN ESTORIL, PORTUGALMAY 14-18 2006

During the 31st PIANC Conference, held in Estoril,

Portugal, an IADC Award was presented to

Ms. M. Carmen Casado-Martínez for her paper on

sediment toxicity assessment in Spanish ports affected

by metallic pollution. Ms. M. Carmen Casado-Martínez

is currently a PhD student in the Physical-Chemistry

Department at the University of Cádiz, Spain. She holds

a Bachelors degree in Marine Science (2001), and a

Masters degree related to the characterisation of

dredged material from Spanish ports using chemical

and ecotoxicological measurements, both from the

University of Cádiz.

Each year at designated events, the International

Association of Dredging Companies grants awards

for outstanding papers written by younger authors.

In each case, the Paper Committee is asked to

recommend a prizewinner whose paper makes a

significant contribution to the literature on dredging

and related fields. The IADC Award includes a

certificate of achievement, publication of the paper in

Terra et Aqua plus € 1,000. The award was established

to encourage young professionals doing research in the

field of dredging and maritime construction.

IADC Secretary General Constantijn Dolmans (left)

presents the IADC Award for young authors to

Carmen Casado-Martínez in at the PIANC

Conference in Portugal. © Courtesy of Portugese

Delegation of PIANC

Figure 3. Location map of Spain with the sampling stations at the ports of Cartagena (C#) and Huelva (H#).


Physico-chemical characterisationThe characterisation of sediments wasperformed on sediments dried at 40ºC for 24-h and followed the CEDEXRecommendations for Dredged MaterialManagement (1994). Grain size distributionfollowed UNE 103 101 and total organicmatter content was estimated by loss ofignition (LOI) at 550ºC and gravimetricdetermination, as recommended for smalldredged volumes. Metals were determinedin microwave acid-digested samples. The concentrations of Cd, Pb, Cu, Zn and Cr were determined using flame orfurnace atomic absorption spectrometry,depending on the metal content. Mercury was determined using the coldvapour technique and for As the hydridegeneration technique was chosen beforequantification using atomic absorptionspectrometry.

PCB congeners #28, 52, 101, 118, 138,153 and 180 and polycyclic aromatichydrocarbons (PAHs) were quantified after extraction with cyclohexane anddichloromethane by means of ultrasoundtreatment, before concentration and clean-up with column chromatography.Determination of PCBs was made with gaschromatography with electron capturedetection (GC-ECD) (EPA 8080) and 12 PAHs(acenaphtylene, acenaphtene, anthracene,benz(a)anthracene, benz(a)pyrene, chrysene,dibenz(a,h)anthracene, phenanthrene,fluoranthene, fluorene, naphthalene andpyrene) were determined with HPLC withfluorescence detection (EPA 8310).Detection limits were 0.8 and 10-30 μg kg-1

dry weight of sediment of PCBs and PAHsrespectively. Recoveries of analytesdetermined ranged from 60% to 120% andall the analytical procedures were checked

with reference materials and allow agreementwith certified values.

Ecotoxicological characterisationBioassays are, amongst other things,required for the characterisation of the toxicpotential of dredged sediments and forenvironmental risk assessment of thedisposal of dredged material. For that reasonmarine bioassays are also recommended in several dredged material managementguidelines (Peters et al., 2002). These guidelines recommend sensitive and standardised sediment-dwelling orsediment-associated test organisms that are reasonably similar to those found – or expected to be found – at the site(Chapman and Anderson, 2005) to assessacute and chronic toxicity. Generally a setof 2-4 bioassays with different taxa arerecommended to assess acute toxicity.

If biological tests are used to clarify gaps of information in decision-making theselection of test species and endpointsshould include sensitive organisms(ecological receptors) in the environmentthat may be exposed to the contaminantsand should address all the exposurepathways that may operate to bringcontaminants into contact with thereceptors. In the particular Spanish case,the framework assumes that the generalgoal of the assessment is to determinewhether a dredged material, proposed for open-water disposal, is likely to causeadverse impacts at the disposal site. Thus, the receptors of concern includeinvertebrates that live in the sediment,animals and plants living on the sedimentsurface, bottom-associated fish, pelagic fishand invertebrates, birds and other wildlife,and humans using the site (PIANC, 2006).

The biological tests derived from theassessment hypotheses are summarised inTable I. Direct benthic effects were assessedin the amphipod Corophium volutator,the polychaete Arenicola marina and theirregular sea urchin Echinocardium cordatum.These three organisms are infaunal benthicspecies in direct contact with the sedimentwhere they are buried. In addition the clamRuditapes philippinarum was included toassess the potential effects of sedimentresuspension events. This commercial clam,also known as the Manila clam, is aninfaunal bivalve that lives buried in thesediments. Contrary to the others, thisspecies is a filter-feeder, feeding on theoverlying water thus it addresses specificallydirect water column effects.

To complete the assessment of direct watercolumn effects the sediment elutriates weretested for toxicity in sea urchin embryosand rotifers. In this way the test setincludes both acute and chronic exposure(i.e. acute are the 10/14-d tests and chronicthe 7-d rotifer population decay test; the embryogenesis success is considered asub-chronic endpoint) and lethal andsublethal endpoints (i.e. survival andburrowing activity). In addition bioaccumu-lation potential of compounds that areknown to bioaccumulate and biomagnify in aquatic food webs, such as PCBs ormercury, was evaluated by measuring theresidue concentrations in clams after thestandard 28-d exposure and lugworms afterthe 10-d of exposure.

Finally the results of the Microtox® devicefollowing the standard protocol for soil andsediments SPT were considered owing to itspotential suitability to screen for toxicity indredged sediment samples.

Table I. Bioassays developed for the sediment ecotoxicological characterisation.

Test species Exposure route Exposure time EndpointVibrio fischeri Whole sediment 30-min Bioluminescence inhibitionCorophium volutator Whole sediment 10-d SurvivalArenicola marina Whole sediment 10-d SurvivalEchinocardium cordatum Whole sediment 14-d Burrowing/survivalRuditapes philippinarum Whole sediment 14-d Burrowing/survival BioaccumulationBrachionus plicatilis Elutriate 7-d Population decayParacentrotus lividus embryos Elutriate 48-h Embryogenesis success


Data treatment and interpretationThe results of the physico-chemical measure-ments were studied in relation to theguidelines recommended in Spain for dredgedmaterial management. These guidelinesfollow an action level approach based onthe use of two different limit values (the so-called Action Levels –ALs) that are usedto classify the sediments in three differentmanagement categories. Despite the highercomplexity of the classification process thechemical concentrations measured in thesediment samples were compared directlywith the national ALs for dredged materialcharacterisation (Table II). In this way it waspossible to identify the category for eachsediment and the contaminants of concernin each area under study.

The biological endpoints were studied inrelation to the negative toxicity controlscarried out with each batch of experiments.This control consisted of a sediment free ofall contamination and toxicity for the solidphase bioassays and clean seawater for theelutriate tests. A difference of 20% betweenthe controls and the test and referencesediments is neither different nor environ-mentally relevant in short-term (e.g. 10-d)acute tests. Thus, if all sediment toxicityendpoints are 20% different from thereference, the sediments are not consideredtoxic even if the difference is statisticallysignificant. As a screening test, the Microtox®

results were compared with the Canadianlimit value established at 1000 mg/L d.w.for disposal licencing (EC, 2002). Statisticalanalyses were performed by means of thestatistical programme STATISTICA®.

CASE STUDY 1: HUELVA

The sediments from Huelva reportedsignificant differences in the proportion offines, the organic matter content and thechemical load showing a clear decreasingtrend along the estuary (Table III). The innerstation (H1) was characterised by thehighest proportion of fines and organicmatter and also the highest concentrationsfor most chemical compounds while H4,the station in the external estuary, was atypical coarse sediment free of allcontamination. Stations H1 and H2, thatare actually more influenced by the rivers,consisted of fine sediments rich in organicmatter with As and Cu concentrationshigher than the corresponding AL2 foraquatic disposal authorisation andintermediate concentrations of Hg, Pb andZn (Table IV). The higher concentration ofNi reported for station 3, located close to apetrol refinery, evidenced the importance ofaddressing point sources in the generalassessment framework. The organicmicropollutants also identified someenrichment in the inner estuary and PCBswere the only micropollutants detectable inthe two inner stations (H1 and H2).

In general the ecotoxicologicalcharacterisation of harbour sediments fromHuelva was in agreement with the resultsof the physico-chemical analyses. The IC50values obtained from the Microtox® deviceidentified the two inner sediments (H1 andH2) as potentially toxic (Figure 4). These sediments reported the highestcontaminant concentrations in sediments,

although the plot of IC50 values indicatesthat some factor, for which the proportionof fines or the organic matter contentaccounts for, may be determining theperformance of this endpoint.

These results are in agreement withprevious studies that reported the highesttoxicities for the inner sediments (Usero et al.,2001) and are explained by the highprecipitation of metals in this area.Precipitation of metallic species such assulfates or carbonates, easily bioavailablebecause of the weak links that bound thesemetals to sediments, occurs in the lowerOdiel and Tinto rivers as a consequence of changes in pH and salinity. This precipitation is higher in the innerestuary and decreases in intensity goingseaward along the estuary because of thegradient in the variables controlling theseprocesses (Usero et al., 2000). Nonethelessthe proportion of fines sediments has beenidentified as one of the main factors relatedto false positives – defined as the samplesthat are considered toxic by this test but donot cause toxicity to other test organisms –when using the Microtox® device forsediment toxicity assessment. On the otherhand, a high proportion of sands maycause false negatives – defined as thesamples that are considered not toxic bythis test but cause significant toxicities toother test organisms – (Ringwood et al.,1997; EC, 2002).

False positives are less relevant from anenvironmental point of view since thesesamples can be properly addressed under atiered approach, but a high probability offalse negatives of toxicity is considered animportant drawback for a screening test.

High toxicities in the rest of sedimenttoxicity tests supported the potentialtoxicity identified for the finer sedimentsthrough a first screening. The sedimentwith a higher proportion of sands, that wasnot a positive of toxicity for the Microtox®,did cause toxic effects and evidence theimportance of sediment properties wheninterpreting the results of the Microtox®

assay. Considering the test species and the exposure routes addressed by eachendpoint, dredged materials from the

Table II. Contaminants determined in sediments and Action Levels used fordredged material management (CEDEX, 1994). All values expressed in mg kg-1

except PCBs, expressed in µg kg-1.Compound Action Level 1 Action Level 2As 80 200Cd 1.0 5.0Cr 200 1000Cu 100 400Hg 0.6 3.0Ni 100 400Pb 120 600Zn 500 3000Σ7-PCB 30 100


Ría of Huelva may pose a risk throughcontact with the whole sediments but alsothrough exposure to the sedimentelutriates. Some decrease in elutriatetoxicity for the inner sediments (H1)indicates that organic matter may decreasethe bioavailability of contaminants bydecreasing its solubility to the waterphases. Nonetheless toxicity throughelutriate and whole sediment exposure wasstill significant. The sediment organicmatter content can be also considered animportant confounding factor when usingorganisms such as rotifers, that should bein starving conditions but may obtain extrafood from elutriates, but it is not relevantfor echinoderm larvae because they do notneed extra food (Apitz et al., 2005).

Tissue concentrations in clams underlaboratory exposure indicated that metalsbioaccumulate from sediments although asignificant elevation in contaminant tissueconcentrations in test organisms does notnecessarily mean that risks to upper throphiclevels are likely. However it is reasonable to

conclude from a failure to statisticallydistinguish the dredged material andreference exposed organisms that risks toupper trophic levels are unlikely (PIANC,2006). Considering that the extent ofbioaccumulation at higher trophic levels in the food chain is unknown, furtherassessments (e.g., trophic transfermodelling and dose calculations) shouldalso be considered for those compoundswith known biomagnification potential(PCBs, mercury).

CASE STUDY 2: CARTAGENA

The sediments from Cartagena were moresimilar in grain size and organic mattercontent than the sediments in the previouscase study that formed a clear gradient ofsediment properties (Table III). The chemicalcharacterisation evidenced that dredgedmaterials from Cartagena are affected by a“cocktail” of contamination consisting ofdifferent metallic and organic compoundsmixed at different concentrations. Dredged

materials from Cartagena would fall intocategory III with high Cd, Cu, Pb, Hg andZn concentrations. These sediments alsoreported high PCBs and detectableconcentrations of PAHs. The Microtox®

evidenced potential toxicity for all sedimentsexcept C3 (Figure 4), that reported thelower proportion of fines, while the rest oftests reported very variable toxicity in thedifferent endpoints measured. All sedimentswere toxic to amphipods and, at thehighest sediment concentrations, toxicity topolychaetes also occurs. On the oppositeside, the sediments evidenced neitherelutriate toxicity nor lethal and sub-lethaleffects on clams.

Considering the results obtained in Huelvait seems that the contaminants bound tosediments from Cartagena are notbioavailable in the water phases althoughchemical measurements were notperformed on the elutriates. Nonetheless,clams bioaccumulate Cd, Cu, Pb, Zn andespecially Hg at higher concentrations thanclams exposed to a reference sediment,which indicates that bioaccumulation ofcontaminants can occur even if toxic effectsare not evident.

LINKING SEDIMENT CHEMICAL AND ECOTOXICOLOGICALCHARACTERISATION

Several approaches are used to linksediment chemical and ecotoxicologicalendpoints that can be used to incorporatebiological endpoints in dredged materialmanagement.

Table III. Grain size and organic content of the sediments (g·kg-1).

Sample % coarse % sand % fines Organic contentH1 0.07 9.71 90.22 20.27H2 0.19 9.60 90.21 10.64H3 0.03 56.02 43.95 6.30H4 80.34 19.65 0.01 1.00C1 3.95 38.24 57.81 10.54C2 5.22 53.59 41.19 9.12C3 0.93 67.20 31.87 7.19C4 0.90 50.01 49.10 9.87

Table IV. Results of the physico-chemical characterisation. All values expressed in mg kg-1 except PCBs, expressed in µg kg-1.

As Cd Cr Cu Hg Ni Pb Zn PCBsa PAHsb

H1 840 4.35 32.9 1938 2.38 34.6 383 2458 200 n.d.H2 531 2.50 24.1 1497 1.99 7.10 385 1857 229 n.d.H3 273 1.32 8.13 772 1.20 129 217 1176 n.d. n.d.H4 4.70 n.d. 9.70 1.90 0.04 0.80 5.30 20.9 n.d. n.d.C1 101 98.5 66.6 666 136 29.0 1397 8661 123 0.91C2 64.7 17.5 45.6 313 32.7 15.3 748 1885 468 1.03C3 88.0 31.9 57.6 453 115.2 19.3 1397 3310 108 0.66C4 62.6 6.79 29.5 171 21.6 19.3 487 901 119 1.24

*n.d. means not detected or lower than the corresponding detection limit; a Σ7-PCBs; b Σ12-PAHs.


Three questions can summarise conciselythe information needed: 1) Are the contaminants of concern present

in the sediment and at which levels? 2) Are these contaminants bioavailable? 3) Are these contaminants causing adverse

biological effects?

The information arising from the assessmentframework should be able to address thesequestions. In the two ports studied, the sediments reported high concentrationsof different metallic and organic compounds(Table V). Huelva was principally affected bymetallic contamination despite that higherconcentrations of some organic compoundswere reported at the inner sampling sites.Even if it is not possible to identify thecauses of toxicity, statistically significantreduction of survival in different benthicorganisms occurs. The sediment-boundcontaminants were bioavailable according to the high toxic effects registered and, in addition, the gradient of toxicity agreedwith the gradient of physico-chemicalproperties thus it is probable that toxicity iscaused by sediment-bound contaminants.

In the second case study, in Cartagena, the relationship between contaminationand toxicity is not straightforward, possibly owing to the different sources ofcontamination in the area and the highercomplexity of the sedimentologicalprocesses in this harbour. The overall toxicitycould be considered significant becausemultiple endpoints exhibit major toxicologicaleffects, and these effects could be in someway related to sediment-boundcontaminants by the decrease in toxicity for the lower sediment concentrations.

Considering these results in the generalframework for dredged materialmanagement it seems that theecotoxicological characterisation supportsthe results of the physico-chemicalcharacterisation. But this type of tests is notprobably considered when a tiered-actionlevel approach such as the onerecommended in Spain is used. When thechemical concentrations are high, dredgedsediments are not afforded furtherecotoxicological assessments to decidewhether or not they are suitable for open-

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60

80

100

ST2

ST3

ST4

ST5

ST6

ST7*

**

*

* *

*

**

*****

**

*

**

**

*

Figure 4. Results of the ecotoxicological characterisation of the sediments selected in this study. Toxicity is identified with

an asterisk. ET1: rotifer population decay expressed as % effect compared to controls; ET2: percentage of abnormal sea

urchin larvae; ST1: Microtox® SPT as IC50 mg/L d.w. basis; ST2: % amphipod mortality; ST3: % polychaete mortality;

ST4: % E.cordatum mortality; ST5: % not buried E.cordatum; ST6: % mortality R.philippinarum; ST7: % not buried

R.philippinarum.


water disposal, and the correspondingmanagement strategy is selected accordingto sediment chemical concentrations alone.

Although the physico-chemical approach isuseful to identify the contaminants of concernand even identify toxicity “hot spots”(Long et al., 2000; Casado-Martínez et al.,2006), certainly the physical, chemical and biological inter-relationships ofsediment/water combinations are far toocomplex to be evaluated through a rathersimplistic approach. Dredging simulation by elutriate tests accurately predictedconcentrations of metal released to thewater column from contaminatedsediments and long-term effects ofdredging because of deposition ofcontaminated material (Edwards et al.,1995; Alden III et al., 1982; 1987).

Further validation programmes havedemonstrated that effluent and surface

water quality predictive methods have good utility for predisposal evaluation ofdredged material intended for uplanddisposal. Thus it can be suggested thatlaboratory toxicity tests can also be useful methodologies for decision-making

when dealing with materials not suitable for open-water disposal.

Table V summarises the informationobtained in each of the methodologiesused to characterise dredged material.

Table V. Results of dredged material characterisation.

Sampling Category Contaminants of concerna Toxic effectb

Station CEDEX Pelagic Benthic (1994) organisms organisms

H1 IIIa As, Cu – +++++H2 IIIa As, Cu + ++++H3 IIIa As, Cu + +++++H4 I -- + –C1 IIIb Cd, Cu, Hg, Pb, Zn, PCBs – ++C2 IIIb Pb, Hg, PCBs – +C3 IIIb Cd, Cu, Hg, Pb, Zn, PCBs – ++C4 IIIa PCBs – +++

a Compounds exceeding the corresponding AL2.b Identified based on one or more toxicity for bioassays.

Table VI. Dredged material categories and management requirements according to Spanish recommendations (CEDEX, 1994).

Category Concentrations Aquatic disposal Type of licence RequirementsI C< AL1 Free aquatic disposal Normal authorisation Sedimentological studies and biological

effects (physical/mechanic)II AL1< C< AL2 Disposal under controlled conditions Special authorisation - Controlled disposal and justification.

- Impact hypothesis.- Environmental control management.- Corrective measures

III C> AL2 Disposal under adequate Special authorisation - Contaminants sources study and management techniques source control measures.

- Isolation techniques and justification. - Impact hypothesis.- Environmental control program. - Corrective measures

Figure 3. The recreational value of the Cartagena yacht marina depends on the cleanliness of the waters.


CONCLUSIONS

If a tiered testing approach is used fordredged material management, the firstimportant step is the compilation of allavailable information. This can sometimesbe enough for decision-making if soundscientific information is available. In Spain,however, previous assessments are onlyavailable for a few ports. In such cases theprocess should be followed to the next tierwhich includes the physicochemicalcharacterisation of the sediments andpossibly some test to screen for toxicity.

Taking account of the advantages of acommercial test the Microtox® offeredpromising results, offering a different toxicitytrend not related to whole sediment toxicitybut also not related to elutriate toxicity(Casado-Martínez et al., 2006). The Spanishrecommendations for dredged materialmanagement (CEDEX, 1994) include a nexttier comprising a battery of toxicity tests forthose sediments with intermediatecontamination or in the case that potentialadverse effects are identified. For theseintermediate contaminated sediments abattery of tests including solid phase bioassaysto assess potential toxicity to benthicorganisms and elutriate tests to determinepotential toxicity to organisms living in thewater column is recommended. In this sensethe test using amphipods seems moresensitive than the test using polychaetes andbenthic sea urchins while embryogenesissuccess seems more recommendable thanthe bioassay using a rotifer population.

REFERENCES

Alden III, R.W.; Butt, A.J.; and Young Jr., R.J. (1987).

Toxicity testing of sublethal effects of dredged materials.

Alden III, R.W.; Butt, A.J.; and Young Jr., R.J. (1982). Open

ocean disposal of materials dredged from a highly industria-

lized estuary: An evaluation of potential lethal effects.

Apitz, S.E.; Davis, J.W.; Finkelstein, K.; Hohreiter, D.W.; Hoke, R.;

Jemsen, R.H.; Jersak, J.; Kirtay, V.J.; Mack, E.E.; Magar, V.S.;

Moore, D.; Reible, D.; and Stahl, R.G. (2005). “Assessing and

managing contaminated sediments: Part II, evaluating risk and

monitoring sediment remedy effectiveness”. Integrated

Environmental Assessment and Management 1(1): 1-14.

Burt, T. Neville and Hayes, D.F. (2005). “Framework for

research leading to aimproved assessment of dredged

generated plumes”. Terra et Aqua 98: 20-31.

Casado-Martínez, M.C.; Forja, J.M.; and DelValls, T.A. “Liquid

versus solid phase bioassays for dredged material toxicity

assessment”. Environ Int (submitted a).

Casado-Martínez, M.C.; Forja, J.M.; and DelValls, T.A.

“Comparative toxicity assessment using the amphipod

Corophium volutator and the polychaete Arenicola marina for

dredged material management”. Environ Toxicol (submitted b).

CEDEX (Centro de Estudios y Experimentación de Obras

Públicas). (1994). Recomendaciones para la gestión del material

de dragado en los puertos Españoles. Madrid, Centro de

Estudios y Experimentación de Obras Públicas, Puertos del Estado.

Chapman, P.M.and Anderson, J. “A decision-making

framework for sediment contamination”. Integrated

Environmental Assessment and Management 1(3): 163-173.

DelValls, T.A.; Andres, A.; Belzunce, M.J.; Buceta, J.L.; Casado-

Martínez, M.C.; Castro, R.; Riba, I.; Viguri, J.R.; and Blasco, J.

(2004). “Chemical and ecotoxicological guidelines for

managing disposal of dredged material”. TrAC Trend Anal

Chem. 23: 819-328.

DelValls, T.A.; Casado-Martínez, M.C.; Riba, I.; Forja, J.M.;

García-Luque, E.; andGómez-Parra, A. (2003). Investigación

conjunta sobre la viabilidad de utilizar ensayos ecotoxicológicos

para la evaluación de la calidad ambiental del material de

dragado. Informe técnico para CEDEX. Noviembre. Puerto Real.

Cádiz, Spain.

DelValls, T.A.; Casado-Martínez, M.C.; Riba, I.; Martín-Díaz,

M.L.; Forja, J.M.; García-Luque, E.; and Gómez-Parra, A.

(2001). Investigación conjunta sobre la viabilidad de utilizar

ensayos ecotoxicológicos para la evaluación de la calidad

ambiental del material de dragado. Informe Técnico para

CEDEX. Puerto Real. Cádiz, Spain.

DelValls, T.A.; Lubián, L.M.; González del Valle; and M., Forja,

J.M. (1996). “Evaluating decline parameters of rotifer

Brachionus plicatilis populations as an interstitial water toxicity

bioassay”. Hydrobiologia, 341: 159-167.

den Besten, P.J.; Deckere, E.; Babut, M.P.; Power, B.; DelValls,

T.A.; Zago, C.; Oen, A.M.P.; and Heise, S. (2003). “Biological

Effects-based Sediment Quality in Ecological Risk Assessment

for European Waters”. J. Soil & Sed. 3: 144-162.

Dillon, T. “The Field Verification Program: a comparative

assessment of dredged material disposal alternatives”.

Proceedings of the CEDA Dredging Days. Nr. 8: 1-12.

Environment Canada. (2002). “Biological Test Method:

Reference Method for Determining the Toxicity of Sediment

using luminescent bacteria in a Solid-Phase Test”. Report EPS

1/RM/42-April 2002. 60 pp.

Edwards, S.C.; Williams, T.P.; Bubb, J.M.; and Lester, J.N.

(1995). The success of elutriate tests in extended prediction of

water quality after a dredging operation under freshwater and

saline conditions.

Goossens, H.and Zwolsman, J.G. (1996). “An evaluation of the

behaviour of pollutants during dredging activities”. Terra et

Aqua 62: 20-28.

Long, E.R., MacDonald, D.D.; Severn, C.G.and Hong, C.B.

(2000). “Classifying probabilities of acute toxicity in marine

sediments with empirically derived sediment quality

guidelines”. Environ Toxicol Chem. 19:2598-2601.

Marguí, E., Salvadó, V., Queralt, I., Hidalgo, M. (2004).

“Comparison of three-stage sequential extraction and toxicity

characteristic leaching tests to evaluate metal mobility in

mining wastes. Analytica Chimica Acta 524 (1-2): 151-159.

Peddicord, R.K. and Dillon, T.M. (1997). Environmental Aspects

of Dredging. Guide 3: Investigation, Interpretation and

Impacts. IADC-CEDA.

Peters, C.; Becker, S.; Noack, U.; Pfitzner, S.; Bülow, W.; Barz,

K.; Ahlf, W.; and Berghahn, R. (2002). “A marine bioassay test

set to assess marine water and sediment quality-its need, the

approach and first results”. Ecotoxicology 11: 379-383.

PIANC (International Navigation Congress). (2006). “Generic

biological assess guidelines for dredged material.” Port

International Association for Navigation and Commerce.

Technical Report Work Group 8 Environmental Contamination.

PIANC (International Navigation Congress). (1997). Dredged

Material Management Guide. Special Report of the Permanent

Environmental Commission. Supplement to Bulletin nº 96.

Ringwood, A.H.; DeLorenzo, M.E.; Ross, P.E. and Holland, A.F.

(1997). “Interpretation of Microtox Solid Phase toxicity test: the

effects of sediment compositions”, Environ. Toxicol. Chem.,

16: 1135-1140.

Usero, J.; Morillo, J.; Gracia, I. Leal, A.; Ollero, C.; Fraidías, J.;

and Fernández, P. (2001). Contaminación metálica y toxicidad

en los sedimentos de los ríos Tinto y Odiel. Consejería de

Medio Ambiente.

Usero, J.; Gracia, I.; Leal, A.; Ollero, C.; and Fraidías, J. (2000).

Calidad de las aguas y sedimentos del litoral de Andalucía.

Plan de Policía (1995-1998). Consejería de Medio Ambiente.


IMO UNEP SOA WORKSHOP ON MARINE POLLUTION PREVENTION AND ENVIRONMENTAL MANAGEMENTThe International Association of DredgingCompanies (IADC) and Central DredgingAssociation (CEDA) joined forces some timeago to develop an Environmental Seminarbased on their series of guides EnvironmentalAspects of Dredging. The aim was to presentthis seminar upon the request of appropriateorganisations. Most recently the seminar waspresented under the auspices of the Interna-tional Maritime Organisation (IMO), UNEP(United Nations Environmental Programme)and State (China) Oceanic Administration.

DALIAN, CHINA

As part of its scientific and technical supportprogramme, every other year the LondonConvention holds its Scientific Group Meetingoutside of its headquarters in London. This year’s meeting was held in Dalian,China, May 29 - June 2. Attached to theMeeting is a workshop to identify technicalco-operation and assistance needs, not onlywith member countries, but also with thosein each region. The International Associationof Dredging Companies (IADC), the CentralDredging Association (CEDA) and the WorldDredging Association (WODA), which hasobserver status at the Convention, supportedthis endeavour by providing training and

opportunities for discussion of dredgingrelated issues. This service has previouslybeen provided at South Africa (1998),Jamaica (2002) and Mombassa (2004).The dredging session of the workshop waswell attended by delegates from fourteencountries representing: Cambodia, Canada,China, Democratic People’s Republic of Korea,Indonesia, Japan, Malaysia, Netherlands,Philippines, Republic of Korea, Singapore,Thailand, United Kingdom, and the UnitedStates. In addition, a delegation of five peoplefrom CEDA’s sister organisation the ChineseDredging Association (CHIDA) was also present.

The facilitators for the dredging part of theworkshop were Mr. Neville Burt, Dr. Chris

ivian, Dr. Andy Birchenough, Dr. ElizabethKim, Mr. Lex Oosterbaan, Dr. Tom Fredetteand Mr. Jeremy Martinich.

THE SESSIONS

The morning session comprised a series oflectures about various aspects of dredgedmaterial management. To further support in

these lectures, delegates received free-of-charge the eight volume set of theCEDA/IADC guides, Environmental Aspectsof Dredging. At the end of each lecture,there was ample opportunity for questions.

The afternoon session provided anopportunity for presentation of papers bydelegates followed by a panel discussionled by the speakers and other invitedexperts. The main lectures were:• “Mind the Gap”: Introduction to the

Dredged Material Management WorkingGroup: Mr. Neville Burt

• Application of the London Conventionto Dredged Material: Dr. Tom Fredette

• Project Planning and Assessment:Investigation, Interpretation and Impact:Mr. Neville Burt

• Management of Dredged Material: Re-use, Recycle or Relocate: Dr. Andy Birchenough

• Machines, Methods, and Mitigation: Mr. Neville Burt

• Beneficial Uses of Dredged Material (a special session requested by CHIDA):Dr. Andy Birchenough

• Environmental Education: DredgedMaterial Management – Sources ofInformation: Mr. eremy Martinich andDr. Tom Fredette

NEVILLE URT

Above, the delegates to the IMO/UNEP/SOA Workshop

came from fourteen countries and three continents –

Asia, Europe and North America.

• Case studies presented by delegatesincluded:– Assessment procedure and

classification for dumping dredgedmaterial: Mr Huo Chuanlin (NationalMarine Environmental MonitoringCentre, SOA, China).

– Dredging Environmental Protection in China: Mr Lin Feng (ShanghaiDredging Corporation and CHIDA).

A Panel Discussion followed, chaired by Mr. Neville Burt, assisted by Dr. Tom Fredette,Dr. Andy Birchenough, Dr. Chris ivian, Dr. Elizabeth Kim, and Mr. Lex Oosterbaan.Often in these types of internationalgatherings there is a reluctance – perhapsbecause of cultural or language problems –to raise questions publicly. To overcome this barrier, a question sheet was preparedand distributed beforehand to delegates.This proved to be a successful way ofbridging any cultural divides, and resultedin a number of stimulating discussionpoints to which the panel was then able to give their attention.

The main points of discussion were:• How are action lists and action levels set

in other countries?• Are there low-tech solutions to waste

characterisation?

• Should a non-member of the conventionhesitate to join if they are unable toimmediately fully comply with thecriteria for ocean disposal activities?

• Would the experts be able to provideassistance to individual countries?

The discussions on all of these points wereinteresting, but it is note-worthy to reflecton the final question: “Would the expertsbe able to provide assistance to individualcountries?” In a follow-up discussion of allthose involved in leading the workshop,general agreement was reached thatcountry-specific workshops could provevery useful. CHIDA in particular is keen onthis idea. Overall, there is no doubt that the workshop and the sets of guides wereappreciated by the delegations, and thatthe aim of CEDA and IADC to informprofessionals in maritime areas related todredging is a worthwhile endeavour.

The next similar event sponsored by IADCand CEDA, “Seminar on EnvironmentalAspects of Dredging”, is scheduled forNovember 6-7 2006 at the TechnicalUniversity Delft, the Netherlands (see page 32).

NEVILLE BURT

joined the staff of H Wallingford in

1964. He received a BSc in Civil

Engineering from Sunderland University

(1971). As an Engineer, Section Manager

and Principal Engineer, he has for many

years spent attention to estuarine and

port siltation. Since 1985 he has

specialised in dredging studies and in

1988 he became a Chartered Engineer

and was appointed Technical Director at

H Wallingford. He is also Chairman of

the CEDA Environmental Steering

Committee and with the support of H

Wallingford, UK has been conducting

dredging seminars for IADC and CEDA.

Some of the speakers on the podium during

the panel discussion, which stimulated

further thought on how assistance could

be provided to individual countries.

IMO UNEP SOA Workshop on Marine Pollution Prevention and Environmental Management 21


PORT 2000, LE HAVRE S NEW CONTAINERTERMINAL REAKWATERS AND DREDGINGOF THE NAUTICAL ACCESS CHANNEL

AN VANDEN ROECK

ABSTRACT

The construction of Port 2000, at Le Havre,France marks a significant expansion ofFrance’s largest port and the fifth largest inEurope. To facilitate the elaborate expansionplans, the project was divided into severalphases. These included dredging of an accesschannel, construction a 10 km protectivebreakwater, building quay walls anddredging a basin on the river side of theport. In addition two beaches were createdand two caissons were manufactured,towed and sunk.

Flexibility in the execution of the works wasnecessary, as environmental and economicissues arose. The original plans wereadapted to mitigate environmental impactsin the Seine Estuary and to maximise there-use of dredged material. The innovativedevelopment of the accurate dynamicallypositioned and automatically guidedspraying pontoon Bayard II was of crucialimportance. Being ready and able to takeadvantage of good weather conditions wasalso essential as the Channel can be hostilewith heavy swells. In addition, because ofthe presence of ordnance from World War IIsite investigation was required before workcould commence.

Port 2000 is expected to have long-lastingeconomic impact on the development ofcontainer shipping and transshipments inthe northern European area.

INTRODUCTION

As the first and the last port of call on theHamburg, Germany to Le Havre, Franceshipping route, the French port of Le Havreneeds a deep draught for welcoming thenewest generation of vessels, for bothinbound and outgoing traffic. Located 365 kmfrom Paris at the mouth of the Seine Estuary,the port of Le Havre is the largest containerport of France and the fifth largest innorthwestern Europe (Figure 1). Existingcontainer terminals at Le Havre have reachedtheir maximum capacity and some are builtbehind the Fran ois I lock making them lessaccessible for larger ships. The increase ofscale of container vessels and the ever strictertime schedules and throughput timesprompted authorities to decide to constructa completely new port. The site chosen is

south of the existing facilities, and is in aplain estuary subject to tidal movementsand directly facing the sea swell.

CONTRACT

In late August 2001, the Le Havre PortAuthority (PAH) awarded the main contractfor the construction of Port 2000 to a jointventure comprising Dredging International,GTM Terrassement (pilot), CampenonBernard TP and inci Grands Projets. The aim of this project, as far as the “wet”side is concerned, was the construction ofthe inner and external breakwaters and the dredging of the maritime access andinternal channel of the new container port.The contract was awarded for an amountof € 218 million including eight options fora total of € 103 million of which four morewill be awarded later. The project wasinitially scheduled for 37 months and wasfinalised in 47 months, taking into accountthe elaborate permitting procedures thatwere encountered and that final dredgingoperations were postponed in agreementwith the Port Authorities.

The original Joint enture offer was withheldowing to the introduction of alternative

Above, Figure 1. The Port of Le Havre at the mouth of

the Seine is the largest port in France, but expansion

was necessary to accommodate the ever-larger

container vessels.

Port 2000, Le Havre’s New Container Terminal: Breakwaters and Dredging of the Nautical Access Channel 23

schedules to minimise the environmentalimpact of the works on the Seine Estuary.In addition, other optimal economicsolutions were sought. In this respect, fine-tuning the phases of execution, themaximising the re-use of dredged material,and the innovative development of theaccurate, dynamically positioned andautomatically guided spraying pontoonBayard II have been of crucial importance.Alternative and beneficiary executionmethods presented to the client, wereclearly decisive in obtaining the contract.

During the first few years of the 21st century,the construction of Port 2000 was thebiggest maritime undertaking in Europe.Construction was completed late in 2005(Figure 2). Remarkably it was exactly acentury earlier that the extension of theport of Le Havre had been begun by anumber of Belgian-based companies. On March 30 2006, the new port wasinaugurated, and reportedly there has been

an increase in vessels calling and incontainer movements per call. Ultimatelythe new facilities will triple containerthroughput to 6 million TEU per year.

SCOPE

The Na ti al A ess Channel The nautical access channel to Port 2000 isdredged to a level of –16m CMH whichallows a tide-independent access for thelargest container vessels. The access routecomprises:– An exterior channel of 4000 m

presenting a bottom width ranging from580 m at its connexion with the existingentrance channel up to 300 m at theentrance of the new harbour.

– An internal channel protected by thesouthern breakwater, having a length of 4000 m as well and a bottom widthof 300 m.

– A turning circle with a radius of 353 m.

Channel slopes vary from 5/1 for theexterior channel and 3/1 for the internalchannels.

The total dredged volume was over 45 million m3, principally sand and silexgravel. Where possible dredged materialhas been reused as reclamation material(11 million m3) and to construct thefoundations and the core of over 10 km of breakwaters (6 million m3 of gravel). A disposal site for the rest of the materialswas available at the offshore site ofOcteville.

Brea watersThe southern breakwater forms the mainprotection of the new port over a length of5900 m. It is a sloped dike constructed ona 50-m wide sub-base realised in dredgedgravel. The external protection is completedon the north side by the northern breakwater(300 m), which is linked to the existingconcrete breakwater of Le Havre (Figure 3).

Figure 2. A schematic drawing of the completed Port 2000.

Bunds 3660 m long were realised on thenorthern side to limit the future platformsbehind the quays. These bunds will bereplaced in the future by quay walls, as the container terminals are expanded.Four quays were actually constructed over a total length of 1400 m, eight more are to be constructed in future contracts. The construction of the quay wall was partof a specially dedicated contract, assignedto a civil contractor.

Inner bunds and outer breakwaters areessentially composed of a core of dredgedgravel, covered by a watertight layer andprotected by several layers of quarry rocks.The southern breakwater has in its mostexposed sections an outer protection madeof Accropodes .

Bea hesAs an added, perhaps surprising, plus pointthe new harbour includes two reclaimed gravelbeaches. The first, called “internal beach” issituated just behind the northern externalbreakwater. Its major purpose is to createan ecologically interesting area to sustain amarine plant called “crambe maritima” whichwere threatened by the extension works.

The second beach, situated at the outer sideof the same northern breakwater, is createdto ameliorate the wave climate at the newport entrance. It should absorb a complex

superposition of waves created by diffractionin the new channel and reflection on existingvertical walls.

M soirsMusoirs is the French word for the twoconcrete caissons, placed at the entrance of the port, marking the northern andsouthern sides. These massive structures(surface: 55 m x 21.5 m x height 30 m)were imposed to reduce the opening at theentrance to 300 m so as to limit internalwave action (Figure 4).

Theoretically, a dike formation could havebeen created to protect of the fairway.Unfortunately this would have requiredsuch an acute slope that a much wider portentrance would have been needed. And awider port entrance would increase wavemovements, agitation and turbulencewithin the inner port that would havedecreased port safety beyond acceptablelimits. Hence it became clear that a verynarrow entrance, which could not be realisedwithout the huge caissons, was preferable.

For the major part the caissons wereconstructed in a drydock in the innerharbour, and then set afloat, towed andsunk on location onto prepared gravelbases between –17 m and –20 m CMH.This unusual part of the project will bediscussed more thoroughly below.

WORKING IN PHASES

From the preliminary studies onwards, the Port Authority was fully aware that the phasing of the works would have amajor impact on the sedimentologicalevolution of the estuary during and evenafter the completion of the works. The Port Authority had to consider thatdiminishing the width of the estuary at theheight of Port 2000 by 20 percent, wouldhave a significant influence on floodchannel displacements and resultingerosions, as well as sand displacement anddeposits. In addition, this is an ecologicallyand also economically valuable areabecause of the presence of the entrancechannel to the port of Rouen 100 kminland on the Seine.

The 776 km long Seine river discharges intoone of the largest estuaries of northwesternEurope, a 30,000-ha maritime, industrial andwetland area spanning more than 5 kmwhich includes both the mouth and thefairway to the port of Rouen. The averagedischarge of 500 m3/s, the important tidalrange of up to 8 m, and very strong currentscause a huge sedimentation transport. This, incidentally, moves the mouth of theestuary westward at a rate of 50 m per year.

For these reasons, “phasing the works”was a serious issue for the Joint enture

Figure 3. An aerial view of Port 2000 with the reclaimed land and protective quay wall under construction.

JAN VANDENBROECK

graduated as a Civil Engineer (MSc) from

the State University Ghent, Belgium.

He joined DEME in 1989 and has worked

as desk operations manager and project

manager on numerous projects. From

2001-2005 he was co-project manager

Marine Works PO T 2000 Le Havre

(France) for the DPAM oint Venture

(GTM DI). Since 2005 he is esident

Manager of Soci t de Dragage

International (SDI), Lambersart, France.


further bunds could be realised with thisgravel. This was continued till a maximumdistance was reached between dredgingarea and the bund realisation. At a distanceof longer than 750 m the economical andtechnical advantages of directly pumpinggravel decreased significantly, because ofthe massive pump capacity required for thetransport of the gravel.

At the same time on the western part ofthe channel an access channel was created,requiring small hopper dredgers with limiteddraughts as the area was very shallow. In alater phase the channel permitted the useof bigger (and more economical) hopperdredgers. It also allowed the transport of 3 million m3 of gravel present on thewestern area to be imported to underwaterstock areas as close as possible to thewestern bunds and dikes to be constructed.This allowed direct pumping from thesestocks by cutter suction dredgers into thegravel basement in a second phase.

Once the inner bunds were realised andsufficient gravel stored by the hopperdredgers in the underwater stock areas, a new phase was started: the construction ofthe western sub-base. The two underwaterstock areas had a total capacity of no lessthan 3 million m3. In order not to obstructtotally the flood currents, only the sub-basewas constructed in this phase; the upperdike construction was started severalmonths later.

The sub-base reaching 3 CMH was sub-merged at high water. This means that only a part of the flood is deviated. The creationof this barrier has as a natural consequencethe deviation of the flood stream and thecreation of a new flood channel, south of thesouthern breakwater. The partial deviationcombined with a close follow up of thisevolution allowed a continuous assessment ofthe evolution of the estuary and the possibilityto adapt the phasing whenever required.

One of the economic risks was the displace-ment of huge quantities of sediment andtheir deposit in the navigation channeltowards Rouen. Therefore this floodchannel creation was “accompanied” bydredging works along its path, removingthe sediments in a controlled way anddisposing of them outside of the estuary onthe site of Octeville. A complementarymeasure with the same objective was the 750 m elongation to the west of thesubmersible dikes on the north side of the same navigation channel.

Once the western foundation was realised,the upper dikes were constructed, using atemporary access dike in the middle of theport. This allowed work to be donesimultaneously to the east and to the westthus accelerating the construction process.The total length of the protection dikes was5.9 km, to which another 3.66 km of theclosing dike had to be added. On average,width at the top was about 50 m.

The temporary division of the inner watersof Port 2000 made by building thistemporary access dike had created separatebasins with a length of 1 to 2 km each.Finally, in order to eliminate the strongcurrents which generate erosion risks, the temporary access dike and the easterndike were opened and closed in oneoperation, thereby sustaining theequilibrium between two huge basins.

DREDGING WORKS

From the beginning several factorsinfluenced the mobilisation schedule of theequipment and in particular the preparationof the dredgers, especially those designated

and an alternative solution was proposed to ameliorate the environmental impact.The phasing proposed in this offer isdescribed as follows. The works would start with dredging theinner basin and creation of the innerbunds. In the first phase this would allow: – only a very limited deviation of the flood

currents, which reach peak values of 5knots (2.5 m per second at high tide).

– and the ability to take advantage of thepresence of gravel in the upper layers,making an immediate construction ofthe eastern bund possible.

After closing the bund, a reclamation areawas made available in which sand could be stocked. The eastern and centralsections of the reclamation cover an area of78 ha and provide a fill of 7.7 million m3.Underneath the dredged sand other gravellayers were situated so that in a second phase

Figure 4. The caissons or “musoirs” being filled and placed at the entrance of the new port.


to operate in the gravel areas: These includeda very tight schedule, combined with offshoreconditions like huge tides up to 8 m andstrong currents. For these reasons thefollowing dredgers were deployed.

Cutter suction dredgers (CSDs) were chosento dig the internal channel, pumping thegravel through the dynamically positionedand guided diffuser Pontoon Bayard IIdirectly into the sub-base of the futurebunds and breakwaters. Sandy materialswere reclaimed in the areas limited by theinner bunds. Significant investments weremade in dredgers like the laandern I ,for instance, by introducing wear-resistantlayers in the pipelines and the pump housesbefore starting the works so as to beprepared for gravel dredging.

Trailing hopper suction dredgers (TSHDs) ofdifferent capacities were needed. At first,small and medium dredgers having a limiteddraught were deployed, so as to initiate aminimum channel in the shallow areas.Thereafter high capacity dredgers as Antigoon(8000 m3), Lange Wapper (13,700 m3) andUilenspiegel (13,700 m3), to accelerate the creation of the channel and to importthe gravel from the western area into theunderwater stock areas were introduced.Dipper dredgers such as the Big Boss andenne were brought in for particular

operations during archaeologicalinvestigations on historic wrecks andassistance with complementary ordnanceclearing operations, as well as thelengthening of the submersible dikesalongside the navigation channel to Rouen.

Pontoons with heavy cranes like De Beverplus an armada of tugs, multicats, floatingand submerged pipelines as well as crewvessels and a survey boat equipped withlatest technologies as multibeam sonarsprovided general assistance (Figure 5).

Table I presents an overview of the mainequipment used. Up to 250 people weremobilised for the operations whichcontinued for three years continuously on a seven days a week, 24 hour a day.

SUB BASE CONSTRUCTION

The sub-base of the dikes had been designedas a massive construction situated in gravelwith a top level at 3 m CMH, directly placedon the seabed. Therefore the constructionhas a variable height going from 3 m forthe shallowest areas up to 6 m for thedeepest. On the top, it has a 50-m width,with a mean section of 350 m2. With atotal length of 10 km, 3,500,000 m3 wasthus required to be placed.

Taking these quantities into consideration,combined with the offshore circumstances,a major concern for the Joint enture fromthe beginning was to develop a techniquewhich could manage the quantity ofreclaimed materials as well as expedite theprogress of the works. This demandedbeing able to take advantage of favourableweather conditions whenever possible.

To meet these requirements a techniquewas devised in which the gravel wasdirectly pumped using a CSD as thedredging unit and a dynamically positionedand guided diffuser (DPGD) pontoon asreclaiming unit. The DPGD measures thedensity and the velocity of the materialsdelivered by the CSD, calculates thequantity of materials needed on the spot to realise the sub-base, and automaticallycontrols the winches of the unit. Thesetechniques allowed the work to progress at300 m sub-base per week, compared withprogress of less than 100 m using theclassic dipper and split-barge techniques.

The DPGD Bayard II was designed to work inthe Seine estuary currents of up to 5 knots.

A major concern however remained thestability of the sub-base once realised. A known phenomenon is that at currents of5 knots small gravel tends to start rolling.

Ta le I. O er iew o the main e i ment sed d ring the three ear ro e t.

T CSD laanderen I 11,728 kW Dredging of gravel material, pumped directly into the sub-base

through DPGD Bayard II. Reclamation of gravel beachesDPGD Bayard II Gravel sub-base construction

Ballasting caissons after their installationCSD Rubens 10,896 kW Sand dredging and reclamationCSD laanderen I 9,862 kW Sand dredging and reclamationTHSD Lange Wapper 13,700 m3 Channel dredgingTHSD Uilenspiegel 13,700 m3 Final Channel DredgingTHSD Antigoon 8,400 m3 Dredging and transport of gravel to the under water stock areasTHSD laanderen I 2,065 m3 Minimum channel realisation and accompanying dredging

works in the new flood channelTHSD laanderen I 1,751 m3 Accompanying dredging works in the new flood channelTHSD Charlemagne 5,000 m3 Gravel dredging for the realisation of the caisson foundationsDipper Big Boss 1,928 kW Wreckage removal and complementary ammunition removalDipper enne 805 kWSplit barge DI 68 1,000 m3

Split Barge DI 69 1,000 m3

Heavy Lifting pontoon Rambiz Installation of the musoirs


As explained in the “phasing” chapterabove, the western part of the sub-basewas planned to remain unprotected forseveral months before construction of theupper dike. Furthermore, the gravel layerspresent in the areas to be dredged containa significant quantity of sand, which is evenmore susceptible to erosion.

Using a partnering concept between client,contractor and the engineering companySogreah, a detailed study programme wasset up to search for a solution. Combiningmathematical and physical models, as well asexperimental try-outs on site, did ultimatelyhelp to adapt execution methods aimed atreducing the erosion of sub-base material.Mathematical modelling was followed byphysical modelling and trials on site.

The solution found was to anticipatepartially the movement the gravel wouldundergo and to adapt the sub-base designin its first phase. It was estimated that300,000 m3 of gravel consumption waseconomised thanks to this adaptation.

VIRGINIE AND STEPHANIE

Two concrete caissons (L x W x H 55 m x21.5 m x 30 m) were constructed in thedrydock “Forme 7” inside the existingharbour. They weighed 13,000 tonnes eachand represented, after flooding, a draughtof about 13 m. These two caissons markingthe entrance of the new port were namedafter the two site secretaries, irginie andStephanie, in tribute to their work.To stabilise these floating “matchboxes”posed on their side during transport, theheavy lifting pontoon Rambi was used. By lifting about 1000 tonnes, it reduced the draught to 12 m.

Utilising pre-installed anchors, the pontooncould be positioned very accuratelyallowing a tolerance of a few centimetres.Taking advantage of the outgoing tide and by ballasting the caissons, the sinkingwas realised in a controlled way. Oncetouch-down took place on the foundationsat –16.50 m CMH, further ballasting wasimmediately executed by pumping gravelthrough the DPGD Bayard II especiallyadapted to this particular situation.

Special attention was paid to theconstruction of the foundations, which alsoused dredged gravel delivered by the graveldredger Charlemagne. Before placing thecaissons, the foundation bed at –16.50 mhad to be levelled with a precision of 5 cm.To meet the demands of this precision, theCSD laanderen I was equipped with alevelling plate instead of the standardcutterhead and a tension wire for preciselydouble-checking the exact level of theplate. Good weather conditions prevailedonce again, and allowing use of thistechnique, which proved decisive for thesuccessful completion of construction.

CONCLUSION

There is no doubt that the realisation of aproject like Port 2000 demands the combinedexperience of engineers, superintendents,captains and their crews. On the otherhand, a project like Port 2000 results in broadening the experience of all theparticipants.

Amongst the challenges faced by the Jointenture were the exposure to difficult

weather circumstances with heavy seaswells, reckoning with strong tidal andcurrent changes, the safety factors of thepossible presence of military ordnance andlimiting the displacement of large quantitiesof sediment and their deposit in thenavigation channel of the Seine. This latteritem has both economic and ecologicalconsequences.

During the 47 months of work 250 peoplewere continuously on the job and each andevery piece of major plant in the DredgingInternational fleet was occupied. Thus as aneconomic driver, the development of thePort 2000 project was a significant force. In the future as well this role will continue,as the long-term aim of the new Port at Le Havre is to become a logistics hub forcontainer vessels in northern Europe. In thisway, the port of Le Havre will provide thelocal population with sustainable growththat is environmentally acceptable andbeneficial for the development of theregion as a whole.

Figure 5. Several of the dredging vessels

can be seen working simultaneously to

prepare the channel.

D C WEDITED BY D. EISMA

Published by Taylor and Francis Balkema, P.O. Box ,2 AK Leiden, The Netherlands. 2 . 2 pages.Hardcover. ISBN: 1 111 . Price: . 12 . .

It is always exciting to open the pages of a newpublication on the subject of dredging. Not only isthere the opportunity to forage for information onnew techniques, experience from past projects,environmental effects data and other related matters,but for anyone who has ever tried to publish a technicaltreatise, there is the added interest in how the subjecthas been handled and the book has been structured.In this case, there could hardly be any doubt about thequality of the information being presented. The list ofauthors reads like a Who’s Who in the dredging worldand, taken as a series of essays on various dredging-related topics, the material is of top quality. Where onecould be critical is in the presentation of this material inbook format without, apparently, the chapters beingmerged sufficiently to eliminate repetition. That said,admittedly it is better to have repetition of goodquality, than poor quality and there are no examplesof the poor quality here. uite the contrary.

The authors and their contributions are as follows (in the order they appear and as credited in the book):– Gerard H. an Raalte: “Dredging Techniques;

Adaptations to Reduce Environmental Impact”.

– Anders Jensen: “Environmental Investigation andMonitoring of the Fixed Links across the Danish Straits”.

– W J lasblom: “Dredging in the Dutch & BelgianCoastal Waters and the North Sea”.

– Neville Burt: “Dredging in UK Coastal Waters”.– Roberto idal: “Dredging in Spanish Coastal Waters”.– Robert E Randall: “Dredging in the United States”.– Peter D G Whiteside: “Dredging in Hong Kong”.– Weidong Sun: “Singapore Dredging”.– Pier ellinga: “Dredging in a Changing Environment”.

The book is edited and introduced by D. Eisma who isa retired professor in Marine Sedimentology at theUniversity of Utrecht and the Netherlands Institute forSea Research, Texel. The book opens with a generalappreciation of the nature of dredging projects anddredging processes, together with a description of howthese are made more environmentally friendly. This isfollowed by seven individual chapters relating to dredgingworks in Denmark, the coastal waters of Holland andBelgium and the North Sea, the United Kingdom,Spain, the United States, Hong Kong and Singapore.The final chapter is a more philosophical perspectiveof the nature of dredging in an environmental context.

Chapters 1 and 3 both contain a substantial amount ofinformation on dredging processes and together couldbe described as a current “state of the art” inventory.Chapter 2, curiously located, and Chapters 4, 5, 6, 7and 8, are more country specific and deal with dredgingworks in the context of their environmental regulations.There is a wealth of detail here. The way to get themaximum benefit from this publication is probably isto read right through the whole book, noting pointsof interest and references, rather than dipping into it,as one might do for a standard text book. Many of the“essays” are based on previously published material,but expanded to fulfil the requirements of the book.As a whole they represent a significant contributionto the state of the art and a valuable reference.

Although an index is provided, the nature of thepublication does not lend itself to easy access forspecific subjects, particularly when they occur on a recurrent basis. However, the knowledge base as a whole is substantial and there is no doubt that theliterature of dredging and its environmental context is considerably enhanced by this publication.

The book is available from Taylor and Francis athttp://www.taylorandfrancis.co.uk

NICK BRAY


OOKS PERIODICALS REVIEWED

Books Periodicals eviewed 29

D K T CEDITED BY DR. JACOBUS HOFSTEDE

Archive for Research and Technology on the NorthSea and Baltic Coast. Special Edition COMRISK,Common Strategies to Reduce the Risk of StormFloods in Coastal Lowlands. ol. , 2 . Colourand b w illus. Softcover. 1 pages. ISSN 2- .ISBN - 2-1 1- . In English.

This compendium of state-of-the-art papers on thecommon strategies to reduce the risk of storm-inducedflooding in coastal lowlands in Europe comes at avery appropriate moment. The matter is of particularinterest, given the Asian tsunami in 2004 and morerecently the storm-induced damages to the GulfCoast of the United States in the wake of HurricaneKatrina, especially along New Orleans, Louisiana.Much of the disaster planning, education, preparationand mitigation measures that could have been of usein the USA are actually addressed in great detail inthis publication. The book is hence a must-have forpersonnel involved with emergency managementand preparedness in coastal areas.

The book, edited by Dr. Jacobus Hofstede, presents aseries of papers that address the various topics relatedto being prepared for coastal flooding. It is estimatedthat approximately 16 million people live in the 40,000square kilometer (km2) expanse of coastal lowlands in the North Sea Region (NSR), which encompass theUnited Kingdom, Belgium, the Netherlands, Germanyand Denmark. Although the various nationalgovernments spend several hundreds of thousands of euros each year on coastal defence, the authorsestablish that much larger amounts are needed in thefuture, and that a coordinated, well-planned effort isneeded to optimise utilisation of these resources.

As part of the efforts of the North Sea CoastalManagers Group (NSCMG) to improve cooperationand coordination between national agencies andgovernments on coastal risk management issues, the“Common strategies to reduce the risk of stormfloods in coastal lowlands – COMRISK” was formed.COMRISK, which lasted from 2002 to 2005 focussedon the following aspects:

“(1) to bring together coastal risk management expertsfrom administration, science and private companiesfrom around the North Sea and beyond,

(2) to exchange experiences and studies of goodpractice on coastal risk management,

( ) to evaluate and further develop innovativeintegrated coastal risk management strategies,considering national regulations and responsibilities,

( ) to initiate and support transnational cooperationon integrated coastal risk management(networking), and

( ) to integrate coastal risk management intostrategies for sustainable management of thecoastal ones in the NSR”.

In April 2005, a workshop was held in Kiel, Germany,to address these aspects and to obtain agreementamongst the various coastal managers. This bookessentially summarises the workshop discussions and conclusions into a series of chapters:Chapter 1 provides an overview to the project.Chapters 2-6 address the evaluation of policies andstrategies, strategic planning, risk perception andpublic participation, performance measures, andhydraulic boundary conditions as it applies to coastalrisk management. Following this, Chapters 7-10present four case studies for Flanders and eeuwsFlanders (Belgium and the Netherlands), Ribe Area(Denmark), Lincolnshire (UK) and Langeoog(Germany). Finally, the book presents strategies forreducing the risk of storm flood in coastal lowlandsand associated integrated risk-based decision-makingprocess in Chapters 11-13.

The authors presents risk management as essentiallycomprising the following basic steps: (a) identification of the nature and extent of flood risks,(b) understanding and addressing the relevant public

perceptions, (c) establishing goals and standards with respect to

the flood risk, (d) establishing strategies and policies to achieve

these goals, and (e) minimising the costs of achieving the goals,

while ensuring that the risk remains acceptable.

Several challenges were identified in the riskmanagement context – primarily, external challenges(sea level rise, ecological regulation, and developmentpressure), physical opportunities and threats (large anddeep flood prone areas and unprotected naturalshorelines), socio-economic challenges (major shorelinecities, designated natural areas, low sense of urgencyfrom citizens), and institutional aspects (limited budgetand staff, policy limitations (management as well asplanning), and limited integration amongst regions). There were considerable variations in riskmanagement philosophy, approaches and planning


amongst the various NSR countries. For example, the UK places a strong focus on cost-benefit aspectsof projects and has permissible legislation (like Denmark), which creates flexibility in fundingprojects. In Germany, a retreat policy for threatenedarea may be followed under extreme situations. The concept of flood risk management is wellunderway in all of the NSR countries, although the specific focus may vary – for example, UK andDenmark stress intervention to mitigate damages,while the Netherlands and Germany focus of flooddefence systems.

The authors conclude that, in a global sense, the strategic planning process can be thought tocomprise of the following key elements: (a) problem formulation and management goals

(establish appropriate policy aims, identify theflood hazard; consider multi-generational planning,cost-benefit criteria, ecological carrying capacity),

(b) flood risk analysis (assessing present and futuretrends, identifying hazard, assessing probabilitiesand consequences of flooding andcommunication of risk),

(c) alternatives analysis (generation of managementoptions and comparative cost-benefit study),

(d) implementation (i.e., carry out the selected plan –improve or manage the flood defences, developbetter warning and forecasting systems, andcommunications plans), and

(e) monitoring and reviewing (performancemonitoring of completed projects, reconsiderationof strategies based on lessons learned).

Within the context of alternatives analysis, theauthors recommend considering:(i) key focus aspects of management measures

(alternate methods and strategies, local site-specific methods considered, flexibility),

(ii) management measures to reduce probability offlooding (primary and secondary defense systemsand emergency planning),

(iii) measures to reduce consequence of flooding(avoid development in flood prone areas, crisismanagement through forecasting and warning,and evacuation), and

(iv) recovery systems (restoration of affected areas,funding mechanisms).

Thus, key steps in a performance evaluation would be: (a) evaluating effectiveness and efficiency of existing

flood defence systems using future risk as aperformance indicator,

(b) evaluating geographic indicators of shorelineposition (where is the defence set? is it stable?should we rebuild or retreat?),

(c) evaluating geometric indicators of defencesystems (e.g., setting shape, slope and crestelevation criteria for dikes and gates using hind-cast and forecast data, establishing dunevolumes that would resist flood events,development of real-time coastal systems toforewarn of imminent danger, and so on),

(d) structural integrity measures (e.g., geotechnicalfailure mode analysis – visual loss, slopegradients, piping and failure; field inspection,data collection and predictions), and

(e) development of long-term performance criteriaand indicators (data needs, present conditionassessment, overtopping potential, failure modes).

The primary failure mechanisms considered in thebook include: dune breaching (for natural and beachshorelines) and dike breaching (for engineeredshorelines). For dune breaching, the equilibriumbeach profile can be compared with the pre-stormprofile to draw conclusions regarding vulnerabilityand probability of failure. The performance of thedune is a function of its geometry, water level,waves and grain size of sediments. For dikebreaching, primary aspects of interest are waveovertopping, geometry and stability of the dikes,erosion potential and rate for the core, andpredicted breach growth rates during floods. These can be simulated with existing hydrodynamicmodelling tools such as Mike21 and Delft3D,amongst others. The authors also point out many of the concerns regarding present use of models and future modelling challenges in this arena.

In terms of technical analysis, geometry, hydraulicsand geotechnical characteristics control the results.Geometry varies with the type of structure and itsfunctions, and is site specific to a certain extent.From a hydraulic perspective, all of the NSR countrieshave fairly extensive networks of water levelmonitoring and wave gauging stations. The datafrom these are used for hind-cast and forecastapplications of various storm events – but thestatistical methods employed vary between thevarious countries. Also, there are differing criteriaamongst countries for the return storm frequencyand permissible overtopping assumptions, although2% run up is still considered as good criteria. For example, while Denmark uses inner structureslope as an explicit criteria for these calculations,


In conclusion, this book presents a wealth ofinformation that is invaluable to emergency plannersand managers who work in coastal flood-prone areas.Periodic review of the flood defence systems (identifi-cation of weak points in the system and appropriatestrengthening measures), evaluation of managementstrategies (communications plans, evacuation andresponse plans) and annual review of nationalemergency response budgets for coastal disasters are vital planning elements. Ultimately, lessons such as the recent New Orleans disaster, can in themselves,be used to develop vital tools for better preparednessin the future – through a failure modes analysis of not only coastal defences, but also the entire policy,planning and response aspects. If such a project were contemplated, this book would be a stronglyrecommended mandatory first reading assignment.

The authors nicely summarise the intent of the book through their final catch phrase: “risk of alltime risk is everywhere and always has been”.It is important that coastal managers and plannersrecognise and communicate this integral part of therisk management philosophy – “that the absence ofoccurrence of risk over long periods of time mayreinforce the myth that these extreme events are not probable however, they are bound to occursometime in the future”. The appropriate realisation,communication and reaction to this simplephilosophy could have been extremely valuable in New Orleans.

RAM K. MOHAN

Germany and the Netherlands have dual criteriadepending on the quality of the top surface for grassdikes. There can be subtle differences in the waveheight and period assumptions as well betweencountries. The book presents these aspects in much more detail. However, since not all of thetechnical terms and abbreviations are fully (andreadily) described, it can be quite challenging to the non-technical reader.

A probabilistic analysis considering the probability ofexceedance of the various storms and resultingeconomic and human losses is a good planning leveltool to determine the desired level of protectionagainst flood events. The analysis would thereforeconsist of defining damage categories, reviewingdata sources, damage analysis and inundationscenarios (through statistical predictions), valuationanalysis and selecting optimal scenarios. Finally, therisk susceptibility can be assessed as the product ofhazard probability and the system vulnerability.

In summary, the authors recommend that risk, beingprobability and consequences of flooding, shouldprovide the basis for flood management decisions. To do this effectively, the uncertainties and unknownsmust first be understood, communicated andmanaged. This can be done through identification ofthe uncertainty, modelling to reduce the uncertainty,and communication of the potential impacts to partiesthat would be potentially affected. The key aspecthere is that the conducted level of risk analysis shouldbe appropriate to the flooding system, the level of

uncertainty, and the needs ofdecision-makers. Propercoordination and data sharingbetween key resource andemergency managementagencies is a critical step indisaster planning and response.Finally, since people living inrisk-prone areas tend tounderestimate potential risks,appropriate education of thosecitizens are a key to the successof any long-term managementprogramme.

The flooding system as depicted

in Die Küste.


SEMINARS CONFERENCES EVENTSSPE RUSSIAN OIL AND GAS 2006T C ECROCUS E OMOSCO RUSSIAOCTOBER

This is a new major international event for theupstream oil and gas exploration and productioncommunity organised by SPE and SpearheadExhibitions Ltd, who also partner to present OffshoreEurope in Aberdeen, Scotland. The main objectivesof the event are to deliver messages by the industryfor the industry, to highlight opportunities in thebiggest oil and gas market and to showcase cuttingedge technologies to the local government, industrydecision-makers and professionals. The conferenceprogramme will cover: drilling, well completions,geology and geophysics, reservoir monitoring &testing, well logging and formation evaluation,facilities engineering, production operations, fluidmechanisms and oil-recovery process, reservoirengineering, gas technology, project management,emerging and peripheral technology, and health,safety and environment.

For further information visit:http://www.russianoilgas.com/ or Spearhead Exhibitions Ltd, Oriel House, 26 The uadrant, Richmond, Surrey, TW9 1DL, UK Tel: 44 208 439 8900, Fax: 44 208 439 8901 Email: russianoilgas spearhead.co.uk

T I P T T ROTTERDAM THE NETHER ANDSOCTOBER

The conference and exhibition, supported by the Portof Rotterdam, is aimed at those involved in thedevelopment and operations of port and terminalfacilities in the container sector. Participants comefrom engineering departments of port authorities,terminal operators, consultancy firms, dredgingcontractors, maritime construction firms and suppliersto the industry. Topics will include: Increasingcapacity, efficient port operations, fender systems,terminal security, breakwater design, ports and theenvironment, maintenance, quay design, concreterepair, dredging, port planning, paving, simulation,port and terminal automation, crane design, newtechnology in cargo equipment, terminal design,impact of large ships of port infrastructure.

For further information:Millennium Conferences InternationalChantry House, 156 Bath Road, Maidenhead, Berkshire SL6 4LB, United KingdomTel: 44 1628 580 246Fax: 44 1628 580 346Email: info millenniumconferences.comwww.millenniumconferences.com

CEDA I D D 2006TAN IERS MOROCCONO EMBER

The threats to the Africa’s coasts as a result ofeconomic and social strains and climate change are growing. Therefore, the theme of the secondInternational Dredging Days will be “Protection of the Coastline, Dredging and SustainableDevelopment”. The first two days will bepresentations and discussions on economicdevelopment, deterioration of and protectionmeasures for the coastlines, and the last day willinclude technical visits to large scale projects, e.g.,the new junction port of Tanger-Med on theMediterranean Sea. English and French are the official languages of the conference.

Beside the conference, an exhibition will take place close to the technical session room. For moreinformation or to book a stand please contact either the CEDA or CEDA-AS secretariat at theaddresses below.

For further information contact:CEDA-AS SecretariatDounia Gharbi or Khadija LeglitiC/o Drepor Ports Dreding PLC5, Rue Chajarat Addor, uartier Palmiers,Casablanca 20100, MoroccoTel. 212 22 95 91 42/ 212 22 95 91 04Fax 212 22 23 47 54/ 212 22 23 26 00Email: secretariat ceda-africa.com orgharbi drapor.com www.ced-africa.com

Anna Csiti, CEDA SecretariatTel. 31 15 268 2575Fax 31 15 268 2576Mobile: 31 6 5050 7336 Email: csiti dredging.orgwww.dredging.org


T S S E ICSE 3RAI CONFERENCE CENTREAMSTERDAM THE NETHER ANDSNO EMBER

This respected event took place in College Station,Texas in the USA in 2002, and then in Singapore in2004. In 2006, Amsterdam will host this thirdsymposium, ICSE-3, for engineers, scientists, decisionmakers and administrators working in all areas ofhydraulics and geo-engineering, which focuses onErose, scour and geoitechnics, scour anticipateddesigns, modeling, field measurements andverification tests, and application areas such as river related, offshore, coastal and port structures.Two days of technical sessions will be followed bytechnical site visits, including to the Delta Works.

For further information contact:CUR, Cora HoogeveenP.O. Box 420 2800 AK Gouda, the NetherlandsTel 31 182 540 650, Fax 31 182 537 067Email: mail icse2006.orgwww.icse2006.org

H 06RO INCIA HOUSE ANT ER BE IUM

NO EMBER

The theme of the International HydrographicConference 2006, known as Hydro 06, is “Evolutions in Hydrography”. It is organised andhosted by The Hydrographic Society Benelux onbehalf of International Federation of HydrographicSocieties. Papers are welcome on all topics related tohydrography such as oceanography, shallow water,inland surveying, charting, dredging support, tides,sediment transport, multibeam, side-scan sonar,positioning, remote sensing, subbottom profiling,and so on.

There will be exhibition stands at the conference,and companies interested in participating shouldcontact the Conference Secretariat for details.

For further information contact:Hydro 06 c/o Technologisch Instituut vzwDesguinlei 214, BE- 2018 Antwerp, BelgiumTel. 32 3 260 0840, Fax 32 3 216 0689Email: info hydro06.comwww.hydro06.com

F I C R C SMARIOTT RI ERFRONT HOTESA ANNAH EOR IA USAJANUARY

“Efficient Assessment, Effective Management,Successful Remediation” will be the theme of thisfourth international conference on remediation ofcontaminated sediments. In addition tocharacterization and standard remediationapproaches, the Conference programme will addressinnovative cience and engineering approaches,management considerations, policies, and guidelinesthat affect decision-making; and the definition anddemonstration of remediation success.

The keynote speaker will be Dr. Robert Ballard,president of the Institute for Exploration, Mystic,Connecticut and director of the Institute forArchaeological Oceanography at the University ofRhode Island. The conference will include plenarysession, exhibits, platform and poster presentations,panel/roundtable discussions. Short courses will beoffered on January 22nd.

For further information see:www.battelle.org/sedimentsconFor inquiries about co-sponsorship, exhibits orregistration contact:The Conference Group, Email: info confgroupinc.comTel: 1 800 783-6338 or 1 614 488 2030Fax: 1 614 488 5747

WODCON VIIIYNDHAM A ACE RESORT

OR ANDO F ORIDA USAMAY JUNE

This is a Call for Papers for the Eighteenth WorldDredging Congress (WODCON III) which will beheld May 27 to June 1, 2007 at the Wyndham PalaceResort and Spa at Disney World in Lake Buena ista,Florida. The theme of the conference and exhibitionis “Global Dredging: Its Impact on the Economy andthe Environment”. This theme will provide a uniqueforum between worldwide dredging contractors,

CALL FOR PAPERS


port and harbour authorities, government agencies,environmentalists, consultants, civil and marineengineers, surveyors, shipyards, vendors, andacademicians who work in the exciting andchallenging fields related to dredging. Importantdiscussions on the impact that dredging or theinability to dredge will have on the world economyand its environment will highlight the programme.

The Technical Papers Committee will review all onepage abstracts received, select and notify authors ofacceptance. Submission of an abstract implies a firmcommitment from the authors to present the papers atthe conference. Conference deadlines are the following: Submission of one page abstracts: October 15, 2006Notification of authors: December 1, 2006Submission of final manuscript: January 10, 2007

Interested authors should mail their one pageabstract to one of the following members of theWEDA Technical Papers Committee:

Dr. Ram MohanBlasland, Bouck & Lee, Inc100 Four Falls Corp Center, Ste 106W. Conshohocken, PA 19428-2950Tel: (484) 530 9119 x35, Fax: (484) 530 9118Email: rkm bbl-inc.com

Dr. Robert E. RandallDepartment of Civil EngineeringTexas A&M UniversityCollege Station, T 77843Tel: (979) 862 4568, Fax: (979) 862-8162Email: r-randall tamu.edu

Mr. Steve Garbiciak. Jr.Blasland, Bouck & Lee, Inc200 S. Wacker Drive, Suite 3100Chicago, IL 60606Tel: (312) 674 4937, Fax: (312) 674 4938Email: sdg bbl-inc.com

Interested CEDA and EADA authors should send their abstract to CEDA or EADA Technical PapersCommittee, CEDA Secretariat.Tel: 31 15 268 2575, Fax: 31 15 268 2576Mobile: 31 6 5050 7336, Email: csiti dredging.orgwww.dredging.org

PIANC COPEDEC VIIDUBAI UNITED ARAB EMIRATESFEBRUARY

After its successful start in 1983, it was decided toorganise the International Conference on Coastaland Port Engineering in Developing Countries(COPEDEC) once every four years in a differentdeveloping country. At the September 2003 meetingin Sri Lanka a merger Agreement between COPEDECand PIANC (the International Navigation Association)was signed and the tradition will be continued underthe auspices of the two organisations. For thisreason, the newest conference will be held in fiveyears instead of four.

The theme of the COPEDEC II will be “Best Practicesin the Coastal Environment”. Topics will include: – Port, harbour and marina infrastructure

engineering, planning and management;– Coastal stabilisation and waterfront development;– Coastal sediment and hydrodynamics;– Coastal zone management and environment;– Coastal risk management;– Short sea shipping and coastal navigation.

Papers should focus on practical applications andmanagerial and environmental aspects of coastal andport engineering in developing industrialised countries,including documented case studies. Prospectiveauthors should submit two-page abstract either as 5 hard copies or 1 digital copy (emailed Worddocument). These should be forwarded prior toFebruary 15 2007 to the Paper Selection Committee.Papers will be reviewed by the International PaperCommittee in April 2007 and authors will be notifiedby mid-June 2007. Final versions of the selectedpapers must be submitted by December 2007.

For further information contact:International Organising Committee, PIANC-COPEDEC c/o Lanka Hydraulic Institute Ltd.177, John Rodirigo Mawatha, Katubedda,Moratuwa, Sri LankaTel: 94 11 265 1306/ 265 0471Fax: 94 11 265 0470Email: Copedec lhi.lkwww.pianc-aipcn.org

Seminars Conferences Events 35

C W CM D MCHI TON DOCK ANDS ONDON UKOCTOBER

Organised by the Institution of Civil Engineers (ICE) onbehalf of the Central Dredging Association (CEDA)and the International Association of DredgingCompanies (IADC) with the support of FIDIC, thistwo-day conference and workshop will be held inLondon in October 2006. The successful completionof maritime construction projects requires skilledcontractors and consultants and clients, bound by afair contract, who are willing and able to worktogether to resolve technical and managementdifficulties as they arise. The conference aims todevelop amongst contracting partners a constructiveapproach to the planning, design and execution ofdredging and maritime construction projects. It willhighlight the capital-intensive nature of maritimeconstruction in contrast with other civil works whichare predominantly labour-intensive.

The target audience comprises consulting engineers,dredging contractors (especially junior projectmanagers), site engineers, assistant engineers, quantitysurveyors, legal counsellors, construction lawyers,insurers, project financiers and advisors to decisionmakers in dredging and maritime construction projects.

The conference will be divided into eight sessions,each comprising keynote lectures presented byinvited specialists from all sides of the internationalindustry. These will be followed by workshop sessionsdealing with the following key topics:– Pre-tender information including ground conditions

and investigations, site morphology and bathymetry,metoc conditions and physical obstructions.

– Environmental aspects including environmentalimpact assessment, the specification ofenvironmental constraints and requirements intender documents, and the development ofappropriate and practical monitoring andmitigation programmes.

– The balance between technical and functionalrequirements, e.g., unrealistic or unspecifiedenvironmental requirements, disproportionatetechnical requirements, the choice of monitoringbenchmarks (zero base measurements).

– Identification of appropriate forms of contract (eg. FIDIC D&R contract, innovative contract forms,D&C, BOT, PPP) and risk allocation in contracts.

– Tender procedures including early involvement ofconsultants and contractors to gain maximumbenefit from their knowledge and experience,achieving a price-quality balance, preparation time,evaluation criteria, transparency and equity withinthe process and fair competition.

– Project finance phasing e.g., cash flow planning,just-in-time’, and the time and finance assigned tothe preparation stage.

– Liability issues such as liquidated damages,consequential damages, gaps between insurancecovers, professional indemnity and general liabilityinsurance.

– Dispute resolution including forms of disputeresolution, pragmatic approach to dispute resolutionand arbitration and the speed of dispute resolution.

Attendance at the conference will attract ContinuingProfessional Development points.

For further information contact the IADC Secretariat: info iadc-dredging.com or visit www.iadc-dredging.com or conferences ice.org.ukOnline registration is opened at:www.iceconferences.com

S E A D

TECHNICA UNI ERSITY DE FT THE NETHER ANDSNO EMBER

This two-day Environmental Seminar is a joint effortof the International Association of DredgingCompanies (IADC) and the Central DredgingAssociation (CEDA). It gives an overview of the environmental aspects of dredging and state-of-the-art dredging techniques.

Dredging is a necessary activity in man’sdevelopment. In the right circumstances, it may also be a very useful tool for remedying pastenvironmental interference. However, by its verynature, the act of dredging and relocating dredgedmaterial is an environmental impact. It is, therefore,of the utmost importance that we should be able todetermine whether any planned dredging will have a positive or negative impact on our environment. Evaluation of environmental impact should examineboth the short- and long-term effects, as well as thesustainability of the altered environment. Besides

THREE NEW SEMINARS FROM IADC


presentation of the subjects, participants arechallenged in case studies to apply the principlesdiscussed in order to get a full understanding of thescope and importance of the environmental aspectsof dredging projects, the management of dredgedmaterial and the effects of environmental guidelines. The seminar is aimed at consultants in dredgingrelated industries and professionals from differentgovernmental bodies, whether municipalities, districtwater boards, ports and harbour authorities orcentral government.

The course fee is € 775. The leaders of the courseare Gerard van Raalte, Engineer, Hydronamic andNick Bray MSc, Dredging Research Ltd. All lecturersare professionals working in the dredging industry ordredging consultancy. Course material includes the 7 part series of guides entitled EnvironmentalAspects of Dredging’. For more information aboutthe guides see the attached IADC publication orderform or www.iadc-dredging.com orhttp://www.dredging.org/content.asp?page 48.

For further information and registration, please contact PAO, Tel: 31 15 278 4619 or by Email: info pao.tudelft.nl

27 I S D R

U F HOTE MANAMA BAHRAINNO EMBER

For (future) decision makers and their advisors ingovernments, port and harbour authorities, offshorecompanies and other organisations that have toexecute dredging projects, the InternationalAssociation of Dredging Companies (IADC) hasorganised for more than a decade the InternationalSeminar on Dredging and Reclamation.

Since 1993 IADC, often in co-operation with localtechnical universities, has provided this week-longseminar especially developed for professionals indredging-related industries. These intensive courseshave been successfully presented in Delft, Singapore,Dubai and Buenos Aires. This year’s choice of Bahrainas a venue is a logical outgrowth of the extensivemaritime infrastructure construction going on in theMiddle East region. As is appropriate to a dynamicindustry, the seminar programme is continuallyupdated. In addition to basic dredging methods, new equipment and state-of-the-art techniques are

explained. The seminars reflect IADC’s commitment toeducation, to encouraging young people to enter thefield of dredging, and to improving knowledge aboutdredging and land reclamation throughout the world.

T To optimise the chances of the successful completionof a project, contracting parties should, from the start,fully understand the requirements of a dredgingproject. This five-day course strives to provide anunderstanding through two types of presentations:– lectures by experts in the field, and– workshops, partly conducted on-site in order to

give the “students” hands-on experience.

Some of the subjects covered are:– port development and maintenance;– project phasing (identification, investigation,

feasibility studies, design, construction, andmaintenance);

– descriptions of types of dredging equipment andboundary conditions for their use;

– state-of-the-art dredging techniques as well asenvironmentally sound techniques;

– pre-dredging and soil investigations, designing andestimating from the contractor’s view;

– costing of projects and types of contracts such ascharter, unit rates, lump sum and risk-sharingagreements.

An important feature of the seminars is a trip on atrailing suction hopper or cutter to visit a dredgingproject being executed in the given geographical area.Each participant receives a set of comprehensiveproceedings with an extensive reference list ofrelevant literature and, at the end of the week, a Certificate of Achievement.

The cost of the seminar will be € 2450; this feeincludes all tuition, seminar proceedings and workshopsand a special participants dinner, but is exclusive oftravel costs and hotel. A group accommodationagreement has been made with the seminar hotel.

Representatives of port authorities, companies, and individuals, with an education level equivalent to at least a BSc or comparable work experience,interested in attending are requested to contact the IADC Secretariat, Mr. Frans-Herman Cammel(cammel iadc-dredging.com) as soon as possible but prior to October 1st 2006, as the number ofparticipants is limited to 25.

International Association of Dredging Companies

COVER

The European Dredging Association has recently prepared a review of European environmental rules, how they interact

with international regulations and the impact of both on dredging and dredged material disposal (see page 3).

IADC

Constantijn Dolmans, Secretary General

Alexanderveld 84

2585 DB The Hague

Mailing adress:

P.O. Box 80521

2508 GM The Hague

The Netherlands

T +31 (70) 352 3334

F +31 (70) 351 2654

E [email protected]

I www.iadc-dredging.com

I www.terra-et-aqua.com

Please address enquiries to the editor. Articles in

Terra et Aqua do not necessarily reflect the opinion

of the IADC Board or of individual members.

Editor

Marsha R. Cohen

Editorial Advisory Committee

Roel Berends, Chairman

Constantijn Dolmans

Hubert Fiers

Bert Groothuizen

Philip Roland

Heleen Schellinck

Roberto Vidal Martin

Hugo De Vlieger

IADC Board of Directors

R. van Gelder, President

Y. Kakimoto, Vice President

C. van Meerbeeck, Treasurer

M. Montevecchi

P. de Ridder

P.G. Roland

G. Vandewalle

International Association of Dredging Companies

number 104 | september 2006 - iadc dredging · jan vandenbroeck flexibility and ingenuity were...

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