the completion

8/2/2019 The Completion

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A STUDY INTO THE CONTROL AND MANAGEMENT OF BALLAST WATER IN

GHANA

BY ANSAH AKROFI

1.0 INTRODUCTION;

Shipping is in fact one of the major driving forces behind the global economy. It is

estimated that more than 80% of the worlds commodities is transported by shipping.

The role of shipping and its related activities at the ports is an indispensable tool for

the development of any nation. With all the benefits shipping brings its negative

impact cannot be discounted. The negative effect of any shipping related activity if left

unchecked or overlooked can lead to detrimental economic and environmental impact

to any society.

Shipping contributes to global pollution via forms such as carbon emissions into the

atmosphere and oil spills through ship accidents or bunkering into the marine

environment. These forms of pollution are of much global concern.

Currently, the issue of aquatic invasive species including the transfer of harmful

organisms in ships ballast water and sediments considered as one of the grea test

threat to global marine biodiversity and ecosystem has become of great concern.

Ships carry ballast water and ballast water carry thousands of marine organisms

which are consequently transferred to new areas. Some of these organisms when

discharged into a new environment have the capacity to wipe out an entire ecosystem

whereby its reversal may be virtually impossible.


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The issue thus lies in finding an environmentally friendly and effective and sustainable

solution to possibly eliminate or reduce any life forms contained in ballast water on

vessels.

In order to understand the need for a more structured and effective control of ballast

water it is important to appreciate how the current situation is affecting the

environment and humans.

Ship ballast water is largely responsible for the spread of invasive species. Other

factors include incrustations on the hulls of vessels and oil platforms, aquaculture,

ornamental aquatic organisms, canal openings, and watercourses transposition.

U. C. Oliveira (2008).

For the past 120 years water has been used as a means of maintaining stability onvessels when it is without cargo, partially loaded or even sometimes when itscompletely loaded with cargo. Formerly, ships used to carry solid materials such assand and stones, but the cost in money and time entailed in loading and discharginggreat quantities of these materials bar their use in modern ships.

B. Baxter (Ed.) Know your own ship 28thedition.

Ballast water is carried on vessels to primarily give the ship sufficient immersion to;

1. Compensate for weight loss;

2. Reduce stress and distortion on the ships hull;

3. Provide transverse stability;

4. Ensure efficient propeller and rudder operation and avoid propeller-induced

vibration and;

5. Avoid excessive trimming of the stern which gives rise to slamming.

Ships normally conduct ballasting or deballasting operations in the ports or in areas

adjacent to these where marine organisms mostly thrive. These operations are

usually undertaken during loading or discharging of cargoes or fuel supplying. The


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volume of ballast water carried varies according to the size of vessel, type of trade

and shipping routes.

Tankers and bulk carriers account for about 76% of the total ballast water volumes

transported globally. . Endresen et al (2004). It is estimated that the shipping

industry displaces about 10 billion tons of ballast water annually with an individual

ship carrying anything from several hundred litres to more than 130,000 tonnes of

ballast water containing between 3,000 and 7,000 species, depending on the size and

purpose of the vessel. C. Shine et. al (2000).

According to history, scientists first recognized the signs of an alien species

introduction after a mass occurrence of the Asian phytoplankton algae Odontella

sinensis in the North Sea in 1903. But it was not until the 1970s that the scientific

community began reviewing the problem in detail. International Maritime

Organisation. Ballast Water Management.

Studies conducted in several countries have shown that small fishes, many species of

bacteria and other microbes, planktonic organisms, pathogenic germs, small

invertebrates and other spores, eggs and larvae of large species can survive in viable

form in ballast water and sediments on ships, even after voyages of several months.

When the ballast water or sediment is discharged into coastal waters, some of these

new species are able to establish reproductive populations that out-compete native

organisms thus multiplying into pest proportions and hence becoming obstinately

invasive causing significant damage to the ecosystem, the economy and human

health. Dandu Pughuic. (2001)


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The spread of invasive species is largely due to the expanded trade and traffic

volume over the last few decades. In January 2011, there were 103,392 seagoing

commercial ships in service, with a combined tonnage of 1,396 million dwt as

compared to 83,544 seagoing ships with a combined tonnage of 799 million dwt.

UNCTAD review of maritime transport. The effects in many areas of the world

such as the United States and Australia have been devastating. Quantitative data

show that the rate of bio-invasions is continuing to increase at an alarming rate, in

many cases exponentially, and new areas are being invaded all the time. It is

estimated that an introduced marine species invades a new environment somewhere

in the world every nine weeks. Volumes of seaborne trade continue overall to

increase and the problem may not yet have reached its peak. International MaritimeOrganisation. Ballast Water Management.

The introduction of new species beyond their natural range can cause massive

economic and ecological damage that can be wrought by rapid unchecked growth of

introduced species in an aquatic ecosystem. Usually, it becomes virtually impossible

to completely eliminate non-native species. These invaders may disrupt the normal

functioning of the ecosystem byout-competing local populations for food, to outrightpredation on important native species such as the introduction of the American comb

jelly (Mnemiopsis Leidyi) to the Black and Azov Seas, causing the near extinction of

anchovy and sprat fisheries. Also the introduction of the European zebra mussel

(Dreissena polymorpha) in the Great Lakes between Canada and the United States

resulted in expenses of billions of dollars for pollution control and cleaning of fouled

underwater structures and water pipes.Carlton, J. T. 1999.


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In addition to this ballast water has been found to carry the bacteria specie known as

Vibrio Cholerae which causes human cholera. Paralytic shellfish poisoning (PSP)

results from the consumption of shellfish products contaminated with neurotoxins

produced by certain species of phytoplankton (floating microscopic plants) within the

group known as dinoflagellates (red tide). This red tide is reportedly transported

through ballast water and causes die-off in marine organism by similarly attacking

their nervous system. Ruiz G. et. Al(2000)

Unfortunately, Africa is not left out as marine IAS is a growing problem in the

continents coastal waters, estuaries and lagoons. Hypnea musciformis (hypnea) is

red algae, originally from Trieste in Italy, and is now distributed throughout the world.

It occurs in coastland, estuaries and marine habitats where it attaches to coral, stones

or shells on sheltered tropical reef flats. Its success is related to its rapid growth rate,

ability to epiphytize other algae and easy fragmentation (IUCN/SSC/ISSG 2004).

Currently, it is present in the coastal waters of Morocco, Namibia, Angola, Congo,

Gabon, So Tom, Cameroon, Nigeria, Togo, Ghana, Cte dIvoire, Liberia,

The International Maritime Organisation (IMO) has been at the fore-front in tackling

ballast water-mediated invasions. In 1997, its member countries adopted voluntary

ballast water management guidelines to minimize the risk of spreading invasive

species. The guidelines recommended the following management and control

measures;

1. Minimising the uptake of organisms during ballasting, by avoiding areas in

ports where populations of harmful organisms are known to occur, in shallow

water and in darkness, when bottom-dwelling organisms may rise in the water

column.


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2. Cleaning ballast tanks and removing muds and sediments that accumulates in

these tanks on a regular basis, which may harbour harmful organisms.

3. Avoiding unnecessary discharge of ballast.

4. Undertaking ballast water management procedures, including:

Exchanging ballast water at sea, replacing it with clean open

ocean water. Any marine species taken on at the source port are

less likely to survive in the open ocean, where environmental

conditions are different from coastal and port waters.

Non-release or minimal release of ballast water.

Discharge to onshore reception and treatment facilities.

Currently, the mid-ocean ballast water exchange is widely considered as an effective

management tool to reduce the risk of ballast-mediated invasion. This procedure

involves two methods; 1. The sequential method; it entails completely emptying

ballast tanks and refilling with open-ocean water. 2. The flow through method; it

involves pumping open-ocean water into a full ballast tank. A. Akiyama and others.

Nonetheless, this method is not a guarantee as ocean current, wind and wave

dispersions may carry unwanted organisms from oceanic areas to shallow areas

where they may start new invasion. Ship design generally does not allow for complete

exchange of ballast and is thus dangerous in certain rough weather conditions; some

water and sediments that remain still have the ability to harbour organisms and

bacteria. Hence, this procedure is being regarded as an interim practice until a viable

and sustainable solution is discovered. S. Cryer and others. BBC (2004)

In Ghana, though there is a growing environmental awareness with an interest and

concern, however, implementing the convention remains a challenge.

Under the International Convention for the Control and Management of Ships Ballast

water and Sediment (BWC 2004), ports are required to provide adequate reception


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facilities to receive ships ballast water and sediments in consistence with international

law. This is to prevent, reduce or eliminate the transfer of harmful invasive aquatic

organisms or pathogens through ballast water. However, the emergence of new

markets under globalization has opened up the ports and shipping routes of the West

and Central African (WACAF) region in which Ghana is a major trading partner in the

sub-region with its two ports. Besides, several ports in the region export bulk

commodities and oil and in return receive large amounts of ballast water. This places

the region at risk as there is a high potential of receiving harmful invasive organisms

into their ecosystem and besides there is the lack of resources and capacity to

implement the new BWC 2004 to address this threat. The threat from ballast water

begins and ends in ports and therefore ports must ensure compliance by ships.

Unfortunately, it can be hardly asserted that the ports in the sub-region are ensuring

compliance despite our vulnerability. Harry Barnes-Dabban, Corporate Estates &Environment Manager for Ghana Ports & Harbours Authority

The country has ratified relevant international marine environmental conventions, but

lack capacity for carrying out the necessary legislative review to enable them to

develop compliant domestic regulations to guide environmental performance. The

main challenges of compliance and enforcement are the political will to see the

environment as a priority area, the lack of adequate resources for environmental

management and the carrying out of compliance and enforcement activities.

M. Chenje et. al (2005)

1.1 PROBLEM STATEMENT


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The problem of invasive species on ships has been known for more than two

centuries. One cannot tell which marine organism may become invasive or not. The

most probable solution therefore lies in finding an effective and sustainable means of

minimizing intake of or perhaps completely eliminating marine organism in ballast

tanks.

The IMO in its effort to curb ballast water-mediated invasion adopted the International

Convention for the Control and Management of Ships Ballast water and Sediment in

2004. However the convention which attempts to regulate the issue on a global basis

is yet to be ratified.

One of the guidelines provided under the convention, known as the mid-ocean ballast

water exchange which is considered to be highly effective in controlling ballast water-

mediated invasion is not implementable in rough weather conditions. Ballast water

exchange involves replacing coastal water with open-ocean water during a voyage.

Other limitations of this procedure are considered on the grounds of safety where

ships stability and stresses may be affected by changing ballast at sea. Also, this

method is considered not fully effective; organisms continue to survive in the

sediment and residual water in the ballast tanks. It has been estimated that the

remaining volume of ballast watermay carry a significant risk due to the organismsassociated with re-suspended sediments in the tanks (International Joint

Commission, 2001).

Unfortunately, Ghana as well as her other African counterpart faces a number of

challenges in ensuring implementation of and compliance with international standards

and practice.


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As Ghana seeks to rake in much income from the oil and gas sector, tankers which

accounts for greater proportions of ballast water discharge across the globe will by all

means have their share of negative impact on the Ghanaian marine environment.

This study will therefore, find out the measures being undertaken to curb ballast

water- mediated invasions, identify the stakeholders involved in regulating the

discharge of ballast water, the challenges faced in implementing and ensuring

compliance with these regulations and review existing regulations to reflect modern

trends in ballast water management.

1.3 OBJECTIVES

The objectives of this work are as follows:

1. Identify the various stakeholders involved in the control and management of

ballast water.

2. Identify the challenges faced in the implementation of and compliance with

regulations with respect to ballast water discharge.

3. Review existing regulations to reflect currents trends in ballast water

management.

1.4 JUSTIFICATION

The case of invasive alien species is now recognised as one of the four greatest

threats to the worlds oceans besides

a. Land-based source of marine pollution


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b. Over-exploitation of living marine resource

c. Physical destruction and alteration of coastal and marine habitat.

This piece of work will absolutely not solve the numerous problems associated with

IAS and ballast water management but the completion of this work will be able to

1. Assist law and policy makers in their attempt to draw up effective plans to

control introduction of IAS and ensure maximum compliance.

2. Raise much awareness about the discharge of ballast water and its

consequences and thus regulate our marine environment with high priority.

3. Bring to light certain lapses faced in the implantation and compliance of

regulation with respect to the marine environment thus recommend probable

solutions.

1-6 Scope of study

This work will cover the operations of the port of Tema, with respect to regulations of

discharge of ballast water. Regulatory bodies such as the Ghana Maritime Authority

and the Environmental Protection Agency will be taken into consideration.


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1-7 Organization

This project work is organised into five chapters. Chapter one introduces the topic

and presents the background study to the work besides the problem statement that

this work seeks to solve, the objectives, justification and scope of study of this work.

The second chapter of this work presents an extensive review of other literature

related to ballast water management.

The chapter three describes the research method and techniques employed in

collecting, analysing and presenting data and finding relevant to the research

problem. The rationale for adopting certain methods and techniques in data

acquisition are explained over here.

Results of the various research findings and interviews are described here in chapter

four.

The final chapter spells out the recommendations suggested by the project and then

concludes the whole work.


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1-8 Reference

A. Akiyama F. Uetsuhara, Y. Sagishima. American Bureau of Shipping (ABS).

Ballast Water Exchange Procedures and their Problems

Carlton, J. T. 1999. Marine Bioinvasions of New England. Maritimes (University

of Rhode Island Sea Grant), Winter 99.

International Joint Commission. 2001. Alien Invasive Species and Biological

Pollution of the Great Lakes Basin Ecosystem. Report of the Great Lakes Water

Quality Board to the IJC.

International Maritime Organisation. Ballast Water Management. Retrieved from

(http://www.imo.org Home Our Work Marine Environment. S. Cryer

(Producer), & D. Rees and S. Cryer (Directors) (2004). Invaders From The Sea

[Motion Picture]. United Kingdom. BBC.

Ruiz G., P. Fofonoff, J. Carlton, M. Wonham, A Hines. 2000a. Invasion of Coastal

Marine Communities in North America: Apparent Patterns, Processes, and

Biases. Annu. Rev. Ecol. Syst. 31:481-531.

Munyaradzi Chenje, Jennifer Mohamed-Katerere. Emerging Challenges ofINVASIVE ALIEN SPECIES cpt. 10

Harry Barnes-Dabban, Corporate Estates & Environment Manager for Ghana

Ports & Harbours Authority

S. Cryer (Producer), & D. Rees and S. Cryer (Directors) (2004). Invaders From

The Sea [Motion Picture]. United Kingdom. BBC.

UNCTAD review of maritime transport 2000 pg. 2 and 2011 pg. 36.


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2-0 Literature review

Marine Invasive species are considered as the second greatest cause of loss to

biological biodiversity after habitat destruction.Carlton, J. T. 2001. Introduced

Species in U.S. Coastal Waters: Environmental Impacts and Management

Priorities. Pew Oceans Commission, Arlington, Virginia.

The main driving force behind the increasing occurrences of alien species invasion is

attributed to the expanding global trade and increased human access to every part of

the world. Considerably, the main vector associated with the chunk of increasing

introductions of alien species is ballast water discharges. GREGORY M. RUIZ,JAMES T. CARLTON, EDWIN D. GROSHOLZ, AND ANSON H. HINES (1997)

Global Invasions of Marine and Estuarine Habitats by Non-Indigenous Species:

Mechanisms, Extent, and Consequences. C. Shine et. Al

Carlton, J. T. (2001) defined a vector as the physical means or agent by which a

species is transported. Ballast water, ships hulls, and the movement of commercial

oysters are examples of vectors.

Today, according to various studies ballast water is recognized as the largest single

vector, besides ship fouling for the transfer of species around the world by

international ocean-going ships. Carlton, J. T. (2001); G. M Ruiz et al. (1997); A. N

Cohen (1998); N Bax et. Al (2003) Nicholas Bax, Angela Williamson, Max Aguero,

Exequiel Gonzalez, Warren Geeves (2003)


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Ballast water is carried on vessels to primarily give the ship sufficient immersion to;

1. Compensate for weight loss;

2. Reduce stress and distortion on the ships hull;

3. Provide transverse stability;

4. Ensure efficient propeller and rudder operation and avoid propeller-induced

vibration and;

5. Avoid excessive trimming of the stern which gives rise to slamming.

B. Baxter (Ed.) Know your own ship 28thedition.

Ballast water is employed when the vessel is at less than maximum cargo load, either

during a transit to load cargo, or after discharging a portion of the cargo before

continuing on to the next port. Therefore, ballast waters can often be a mix of waters

from many ports (Carlton et al., 1995 in Tzankova, 2000). Also, it is often discharged

in order to raise the ship when entering shallower ship channel areas.

The volume of ballast normally carried varies, depending on the type of vessel. For

example bulk carriers could have ballast capacities ranging from211 MT to 47 000MT whiles ballast capacities for tankers could also range from 1500 MT to 28 000 MT.

Ballast water enters a ship through intakes located below the water line. These

intakes are typically covered with grates or strainer plates with openings of about half

an inch or larger, although corrosion can further enlarge these openings and the

plates sometimes fall off which could permit entry of larger organisms. The function of

the strainer plates is to prevent damage to the ship's pumps and from objects that


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might otherwise be drawn in, although when present and in good condition they would

incidentally serve to prevent the introduction of large organisms into ballast tanks.

Depending on the level of the tank relative to the water surface, water may be taken

on or discharged either by pumping or by gravitational flow. Ballast water is generally

carried in several different compartments on board ship, often in tanks set aside for

that purpose (called "segregated or "dedicated ballast tanks), although some bulk

carriers and tankers may carry ballast water in their cargo holds ("unsegregated"

tanks).

Ships are said to be "in ballast" when they carry ballast and no cargo, and "in cargo"

when they carry some cargo. Ships loaded with cargo may also carry considerable

quantities of ballast water. When ships have pumped out all the ballast water that

they can, they may be described as having "no ballast on board" (NOBOB).

However a substantial amount of water, perhaps tens or even hundreds of thousands

of gallons, often containing a high concentration of sediment, may remain in ballast

tanks after the pumps have lost suction. This is known as unpumpable ballast or

dead water, and while the amount involved may seem insignificant to a mariner

concerned with ship operations, it may be quite substantial to a biologist concerned

with the potential for transporting marine species.

Although the use of ballast water is very essential for the safe operation of a vessel, it

is simply inevitable to draw in potential invasive alien species along with ballast water.

Carlton 2001 stated that Studies in the U.S., Germany, Scotland, Wales, Australia,

and Hong Kong, reveal a remarkable array of living marine organisms, representing

all of the major and most of the smaller groups of life.


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Many species are in their larval, or dispersal, stages, becoming bottom-dwelling

organisms as adults. These include sea anemones, worms, barnacles, crabs, snails,

clams, mussels, oysters, bryozoans, sea urchins, sea squirts, seaweeds, many

others. Other species live permanently as adult organisms in the water. These include

diatoms, dinoflagellates, copepods, jellyfish, and many others. Certain viruses and

bacteria that cause human epidemic cholera have also been detected in ballast

water. PG. 11

N. Bax ET. Al (2003) observed that at any given moment some 10,000 different

species could be transported between bio-geographic regions in ballast tanks.

IMPACT OF INVASIVE ALIEN SPECIES

Invasive species are well noted for their impact on the environment, ecology,

economy and human health.

Environmental impacts include loss of native biodiversity due to preying on or

competing with native species, decreased habitat availability for native species,

smothering and overgrowth, parasites and disease, as well as hybridisation, causing

genetic dilution. For example, the Mediterranean mussel (MytilusGalloprovincialis) is

dispersed with ballast water and by fouling ship hulls, and is now well established

intemperate regions around the globe. It has displaced several South African native

mussel species, and appears to out-compete and hybridize with its close relatives on

the US west coast.


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Changes to ecosystem function include changes in nutrient cycles and decreased

water quality. In Africa and South East Asia there is a number of problems caused by

the IAS of water hyacinth. The dense mats of these plants clog waterways with their

ability to take over entire lakes and rivers. The plant causes the lowering of dissolved

oxygen levels and thus reducing the amount of fish able to live in the water ways.

This has an impact on the fishing and shipping industry. The water hyacinth takes up

large quantities of vital nutrients from the water and inhibits the growth of native

plants. When the water hyacinth dies it sinks to the bottom of the water body, thus

causing the water to become eutrophic due to the release of all the nutrients taken

up. The deterioration of the water way threatens clean drinking water and thus has an

impact on human health.

Impacts to human health and wellbeing include decreased recreational opportunities,

and overgrowth of aquifers and smothering of beaches, as well as parasites and

disease. The spread of toxic phytoplankton and increasing occurrence of harmful

algal blooms are of significant health concern. Toxic dinoflagellates have been

introduced in ballast sediments to some and perhaps several countries around the

Pacific Ocean. These microscopic organisms can become phenomenally abundant,

producing discolorations of the sea known as red tides. Red tides may kill fish or

invertebrates by clogging their gills, and some produce human neurotoxins that

accumulate in clams or mussels, sickening and sometimes killing the people that eat

them. During the 1991 South American cholera epidemic the bacterium that causes

cholera (Vibrio cholerae)was discovered in oysters and fish in Mobile Bay, Alabama.

The U. S. Food and Drug Administration then sampled the ballast water of 19 ships

arriving in Gulf of Mexico ports from Latin America and found the South American

epidemic strain of cholera in 5 of them.


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Economic impactscan result from interference with biological resources that support

fishing and mariculture (e.g. collapse of fish stocks), interference with fisheries (e.g.

fouling of gears), disruption to tourism, damage to infrastructure (e.g. through fouling)

and costs of treatment, clean up or control. European zebra mussels, (Dreissena

polymorpha), were discovered in the Great Lakes, U. S of A in the late 1980s.The

mussels have caused expensive problems, blocking the pipes that deliver water to

cities and factories and cooling water to nuclear-and fossil fuel-fired power plants;

attaching in enormous numbers to ship and boat hulls, marine structures and

navigational buoys; and covering beaches with sharp-edged mussel shells and rotting

mussel flesh. The average cost of damages from this invasion has been estimated at

$360,00O/year for affected cities and industries and $825,00O/year for nuclear power

plants, with maximum reported costs through 1995 of $600,000 for one shipping

company, $1.5 million for a single factory, $3.7 million for a water treatment facility,

and $6 million for a power plant.

2-1 MANAGEMENT OF BALLAST WATER

Identifying the vectors or pathways of invasive alien species is a significant step in

reducing further introductions. The next step is then to find practical and effective

means to reduce or utterly prevent any new introductions.

The aim of ballast water management is therefore to prevent or reduce further

introductions of alien aquatic species into the marine environment.

However, the various management and control measures being proposed or yet to be

implemented are now yet to have a global impact with respect to the scale of


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expanding international trade and travel multiplying the introduction of species into

the environment. Carlton, J.T. 2001b. Introduced species in U.S. Coastal Waters.

Report prepared for the Pew Oceans Commission, October, 2001.

The IMO in its International Convention for the Control and Management of Ships'

Ballast Water and Sediments, 2004 sets out the definition of ballast water

management which states that;

Ballast Water Management means mechanical, physical, chemical, and biological

processes, either singularly or in combination, to remove, render harmless, or avoid

the uptake or discharge of Harmful Aquatic Organisms and Pathogens within Ballast

Water and Sediments.

Currently, there are mainly two practical measures being undertaken in the

management of ballast water.

These are the; i. The mid-ocean ballast water exchange and

ii. Treatment of ballast water by physical, chemical and

mechanical means on board vessels.

Mid-Ocean Ballast Exchange

Ballast water exchange is presently considered as the single most practical method

for ballast water management. The primary purpose of a mid-ocean exchange is to

remove the coastal water containing coastal organisms, and load only open-ocean

water in the ballast tanks. On arriving at its destination, the ship would then release

into coastal waters only open-ocean organisms. Such organisms are not expected to

survive, or at least not to thrive, in the coastal zone or to compete effectively with

organisms adapted to coastal conditions. Cohen, A. N. 1998. Ships' Ballast Water


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and the Introduction of Exotic Organisms into the Sun Francisco Estuary:

Current Status of the Problem and Options for Management. San Francisco

Estuary Institute, Richmond CA.

According to the regulation B-4 of the ballast water convention, it states that ships

shall conduct such ballast water exchange at least 200 nautical miles from the

nearest land and in water at least 200 metres in depth.

Regulation D-2 of the convention also requires that ships performing ballast water

exchange shall do so with an efficiency of at least 95 per cent volumetric exchange of

Ballast Water.

These measures provide a very substantive way of reducing further introductions of

marine species when adhered to. It is very practical and currently both

administrations and port states base on the convention in place to ensure the proper

execution of the exchange procedure.

Ballast water exchange can be accomplished by three main methods

i) Sequential method A process by which a ballast tank intended for the carriage of

water ballast is first emptied and then refilled with replacement ballast water to

achieve at least a 95% volumetric exchange.

ii) Flow-through method A process by which replacement ballast water is pumped

into a ballast tank intended for the carriage of water ballast, allowing water to flow

through overflow or other arrangements. At least three times the tank volume is to be

pumped through the tank.

iii) Dilution method A process by which replacement ballast water is filled through

the top of the ballast tank intended for the carriage of water ballast with simultaneous


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discharge from the bottom at the same flow rate and maintaining a constant level in

the tank throughout the ballast exchange operation. At least three times the tank

volume is to be pumped through the tank.

Adapted from the American Bureau of Shipping; Guide for Ballast Water

Exchange, July 2010.

2-1-1 Sequential Method

The sequential method entails completely emptying ballast tanks of the coastal

waters and refilling with ocean water. Emptying of certain tanks may lead to

significantly reduced stability, higher vessel structural stresses, high sloshing

pressures and/or reduced forward drafts which may then increase the probability of

bow slamming. American Bureau of Shipping.

Researchers found that 70 - 90% of the ballast water is exchanged when this method

is conducted properly.

A.N Cohen 1998 observed from experimental exchanges, 96-100% efficient

exchange of water in 3 deck tanks and based on mean salinity some coastal

zooplankton remained at less than one organism per m3.

According to a report made by the Pacific Ballast Water Group, the cost of this

procedure was relatively low compared to other potential forms of treatment.

2-1-2 Flow through/Dilution method

The flow through and the dilution method are both generally referred to as the pump

through method.


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The flow-through method involves pumping replacement ballast water into the bottom

of a full ballast tank, forcing existing ballast water out through an overflow or other

arrangement. ABS BWE Guide July 2010

In the dilution method, replacement ballast water is filled through the top of the ballast

tank and simultaneously discharged from the bottom at the same flow rate while

maintaining a constant level in the tank throughout the exchange operation. ABS

BWE Guide July 2010

The American Bureau of Shipping recognizes that the flow-through method as well asthe dilution method do not typically alter stability, hull girder stress and vessel attitude.

It therefore eliminates concerns of exceeding shear force and bending moment limits

and concerns related to shallow forward and aft drafts and extreme trims. An

investigation conducted by Lefteris Karaminas, Hasan Ocakli, Katherine Mazdon, and

Paul Westlake stated that care is needed in the application of the flow through

method which could result in the resizing of pumps due to the increased resistance

and higher workload, fitting of new pumping and piping systems, over-pressurization

leading to structural damage and icing on deck in sub-zero temperature conditions.

Both methods are relatively of low cost compared to other potential treatment

methods according to the Pacific Ballast Water Group. However, it takes between 3-4

days to complete ballast water exchange during the flow through method.

A. N Cohen (1998) observed from experimental ballast water exchanges that the flow

through method in combined double-bottom and topside tanks, with the ship in port


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(static conditions), eliminated 75% of dead plankton by replacing 3 tank volumes; with

the ship at sea, eliminated 70% of dead plankton by replacing I tank volume; 88% of

water (estimated with dye) by replacing 2 tank volumes; and 95% of dead plankton

and 96% of water by replacing 3 tank volumes.

CHRISTOPHER COSTELLO, JOHN M. DRAKE, AND DAVID M. LODGE (2007)

used a theoretical modelling to determine the efficacy of ballast water exchanges

after the procedure had become mandatory for ships entering the North American

Great Lakes, aimed at reducing new introductions. The outcome of the result failed to

prove either the effectiveness or the counter-productivity of ballast water exchange.

The research did not also specify the type of procedure involved such as the flow

through method or the sequential method but rather on a more general basis.

A. N Cohen (1998) considered the various procedures which may be conducted for

ballast water exchange. The work was based on various experiments and

observations.

Theoretically, ballast water exchange procedures can be extremely significant in

reducing ballast water-mediated invasions if properly conducted. Based on

experiments, the Smithsonian Environmental Research Centre (SERC) found that

BWE can be highly effective, removing on average 88-99% of the original coastal

water and 80-95% of coastal planktonic organisms from ballast tanks (compared to

control tanks), when conducted according to current requirements. The experiments

included both methods of exchange and a range of vessel types, focusing on

changes in the concentration of zooplankton, but did not evaluate efficacy for

phytoplankton.


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However, currently, most ships are not suitably designed to carry out any of the

exchange procedures as required by IMO. All of the above procedures cannot be

carried out in rough weather conditions on the open ocean which can extremely limit

its effectiveness. A. N Cohen (1998) and Costello et. Al conducted their experiments

and observation based on modelling. Most regulations on exchange procedures such

as the Ballast Water Exchange Guide by ABS, Canadas Ballast Water Control and

Management Regulations required a 95% volumetric exchange of all ballast water

with the objective of significantly reducing any forms of life existing in the ballast

tanks. However, measures to ensure a vessel has conducted up to 95% exchange of

the ballast water in the open-ocean with very less life form in the ballast tanks can

become challenging with respect to finding out which organisms were eliminated and

which remained. It is clear that these procedures are not as efficient as already noted

by the IMO and that these procedures are being regarded as an interim practice.

Due to the numerous limitations and risks associated with the various exchange

procedures, there have been proposals and works to develop treatment systems both

onshore and offshore.

2-2 Ballast Water Treatment Systems

Ballast water treatment systems are being regarded as the most effective and

efficient processes in the reduction of invasive species. The requirement for ballast

water treatment has arisen from the requirements of regulation D-2 of the Convention.

Regulation D-2 of the Ballast Water Convention sets out the performance standard

ballast water treatment systems must meet. Treatment systems must be tested and

approved in accordance with the relevant IMO Guidelines. See table below for

performance standard according to the regulation D-2.


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In response to this, administrations, industry stakeholders and research laboratories

are already joining forces in the development and testing of promising Ballast Water

Treatment (BWT) technologies. However, most of these technologies are yet to be

approved and implemented for both onshore and offshore.

ORGANISM CATEGORY REGULATION

Plankton, >50 m in minimum

dimension

< 10 cells / m3

Plankton, 10-50 m Toxicogenic < 10 cells / ml

Vibrio cholera (O1 and O139) < 1 cfu* / 100 ml

Escherichia coli < 250 cfu* / 100 ml

Intestinal Enterococci < 100 cfu* / 100 mlTable 1.0 IMO D2 standards for discharged ballast water

* Colony forming unit

Adapted from the Lloyds Register (February 2010) Ballast Water Treatment

Technology Current Status.


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There are two generic types of process technology used in ballast water treatment:

I. solid-liquid separation;refers to the separation of suspended solid material,

including the larger suspended micro-organisms, from the ballast water, either

by sedimentation (allowing the solids to settle out by virtue of their own

weight), or by surface filtration (removal by straining; i.e. by virtue of the pores

in the filtering material being smaller than the size of the particle or organism).

II. Disinfection;This process removes and/or inactivates micro-organisms using

one or more of the following methods:

chemical inactivation of the microorganism

physicochemical inactivation by irradiation with ultraviolet light, which

denatures the DNA of the micro-organism and therefore prevents it from

reproducing. Ultrasound or cavitation are also physico-chemical

disinfection methods

deoxygenation is achieved by reducing the partial pressure of oxygen in

the space above the water with an inert gas injection or by means of a

vacuum which asphyxiates the micro-organisms.

2-2-1 Ballast Water Treatment Techniques

Filtration

Filtration is an environmentally sound technique for the control of ballast water

organisms that works by capturing organisms and particles as water passes through

a porous screen, filtration medium or stacks of special grooved disks.


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Removal of larger organisms such as plankton by filtration requires a filter of

equivalent mesh size between 10 and 50m. Such filters are the most widely used

solid-liquid separation process employed in ballast water treatment, and their effective

operation relates mainly to the flow capacity attained at a given operating pressure.

Maintaining the flow normally requires that the filter is regularly cleaned, and it is the

balance between flow, operating pressure and cleaning frequency that determines the

efficacy of the filtration process.

Filtration is relatively expensive, costing an estimated $0.060.19$ per ton of ballast

water (including capital cost). Lloyds Register (2010)

Hydrocyclone technology is also used as an alternative to filtration, providing

enhanced sedimentation by injecting the water at high velocity to impart a rotational

motion which creates a centrifugal force which increases the velocity of the particle

relative to the water. This force causes the heavier particles to move to the outside

where they are captured by a weir-like feature near the discharge point. Lloyds

Register (2010)

Both hydrocyclone technology and filtration are effective for larger particles. These

processes are often proposed as a first step to be followed by additional treatment,

such as Ultra Violet disinfection.

2-3-1 Disinfection

A number of different chemicals (biocides) or chemical processes have been

employed in the treatment of ballast water. Treatment facilities require IMO approval

for the use of chemicals referred to as Active Substances (AS).


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The efficacy of these chemical processes varies according to the conditions of the

water such as pH, temperature and, most significantly, the type of organism. These

Active Substances include;

I. Use of Chlorine concentrations in eliminating marine life contained in

ballast water.

II. Chlorine dioxide is normally produced in situ, although this presents a

hazard since the reagents used are chemically hazardous.

III. Peracetic acid and Hydrogen Peroxide are infinitely soluble in water,

produce few harmful by-products and are relatively stable. However this

reagent is relatively expensive, is dosed at quite high levels and requires

considerable storage facilities.

IV. Ozone yields far fewer harmful by-products, the most prominent being

bromate, but requires relatively complex equipment to both produce and

dissolve it into the water.

V. Menadione, or Vitamin K, is unusual in that it is a natural product (although

produced synthetically for bulk commercial use) and is relatively safe to

handle. It is under the proprietary name Seakleen.

Other AS include; Acrolein Glutaraldehyde

Cohen, A. N (1998) observed from laboratory experiments that biocides such as

chlorine (tested at 10-2,000 ppm of free chlorine) and hydrogen peroxide (tested at

100-60,000 ppm) were effective in eliminating dinoflagellates cysts when delivered

only at high concentrations (2mg/l). Chlorine is relatively inexpensive and virtually

ineffective against cysts. Chlorine also leads to undesirable chlorinated by-products,

particularly chlorinated hydrocarbons and trihalomethanes.


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It was however realized that some of these chemicals may be non-feasible for other

reasons as well, including lack of adequate storage space on ships, reduced

effectiveness in water with sediment or organic material, corrosiveness, and concerns

about discharging chlorinated water into the environment.

Nonetheless, some biocides (chlorine, copper and silver ions) can be electrolytically

generated from seawater, but expensive equipment and a substantial supply of power

was needed.

The use of biocides can be very effective in achieving the required levels of

organisms. However these treatment plants are very expensive to build and operate.

Discharge of these chemicals could have detrimental effects on the marine

environment with related health risks.

Physical disinfection

Ultraviolet radiation;The process employs amalgam lamps surrounded by a quartz

sleeve which can provide UV light at different wavelengths and intensities.

The process relies on good UV transmission through the water and hence needs

clear water and unfouled clean quartz sleeves to be effective. The removal of water

turbidity (i.e. cloudiness) is therefore essential for effective operation of the

While UV kills bacteria and other micro-organisms, it may not be effective for larger

organisms, cysts and spores, algae and fungi, and its effectiveness is reduced in

water containing suspended matter. For that reason, UV is generally considered to be

practical only after some form of filtration system. Lloyd Register (2010)


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Ultrasound; this approach has shown potential to be a very effective secondary

treatment technology. It can produce extreme pressure and temperature change to

destroy microorganisms and bacteria. However, this is still a new technology and

there are potential challenges with large-scale operations related to consistent

application, energy requirements and equipment durability. Until further testing and

research is completed, its use as a viable secondary treatment is unable to be

assessed.

Heat treatment;Laboratory tests have shown that heating water to 40-45 C (104-1

13 F) for 30- 90 seconds will kill many species of dinoflagellate cysts.Calculationsfor one bulk carrier indicate that to sufficiently heat its 12 million gallons of ballast

water would require 45-90 megawatts of power in addition to the 20 megawatts

available as waste heat, or 2-4 times the power generated by the ship's main engine.

In addition to issues of cost and space, concerns include thermal stresses to the

vessel and thermal pollution from discharging heated ballast water. Cohen, A. N.1998. Ships' Ballast Water and the Introduction of Exotic Organisms into the

San Francisco Estuary: Current Status of the Problem and Options for

Management. San Francisco Estuary Institute, Richmond CA.

Other physical treatments methods available include; mechanical damage, magnetic

treatment and electrocution.

Overall, it was observed that the efficacy of ballast water treatment systems was

better than the IMO D-2 standards according to researchers from the Royal

Netherlands Institute for Sea Research.


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The numerical abundance of the viable organisms as indicated in the BWM

Convention as well as the number of other (phyto)plankton declined substantially,

often to nearly undetectable values.

On- Shore Treatment

Although, various ballast water management procedures and treatment facilities were

basically experimented and implemented with on-board approaches, most of these

treatment facilities discussed above could also be undertaken on land.

On- shore treatment remains another viable approach in effectively controlling

introduced species. Nevertheless, there has been less study of on-shore treatment of

ballast water than of on-board treatment and ballast exchange, however feasibility

studies conducted for the Canadian and Australian governments estimated costs for

on-shore treatment approaches that compared favourably with other treatments. A. N

Cohen (1998)

A.N Cohen (1998) compared both on-shore and on board approaches with respect to

their advantages and disadvantages and found that the advantages of onshore

approach outweighed on-board approach.

Stemming the tide (1996) mentions that the main advantages of onshore treatment

are:

a. The port authorities could operate and maintain the facilities and could monitor

them routinely to determine the treatment extent and effectiveness;

b. Operations onshore allow better control of the treatment, in comparison to

potentially difficult operating conditions on board the ship;


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c. The waste coming from the treatment process can be eliminated in an

environmentally acceptable manner, under the control of an appropriate

authority;

d. Onshore treatment plants can merge the treatment alternatives in order to

ensure better efficiency in the process, as well as it may be done on board the

ship. Stemming the tide. 1996. Controlling introductions of

nonindigenous species by ships ballast water. Committee on Ships

Ballast Operations, Marine Board, Commission on Engineering And

Technical Systems, National Research Council, National Academy Press,

Washington, D.C., 1996.

Cohen (1998) cited the following advantages:

a. Ballast water can be treated with sewage disinfection station in the vicinity of

the port or of the municipal;

b. Methods similar to filtration can be applied to on-land stations, removing many

tough life stages (cysts and spores), as well as organisms and inorganic

sediments, and it can combine methods such as biocides, UV that are cheaper

and more efficient;

c. Higher safety for the crew, since there is no contact with toxic components of

treatments on board, as well as lower corrosion problems and structural stress

due to temperature variations in some methods;

d. Additional room in the vessel (especially in the engine room) is not required,

the ship energy consumption is not increased, and there is no new facilities or

modifications of the original design;


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e. The method can provide an economy of scale in construction and operation of

on-shore stations in contrast with the number of devices required on ships to

handle the same amount of ballast water.

Gollasch et al., (2007) mentions the advantages as follows:

a. Currently, the onshore treatment of ballast water of tankers is an example of

the possibility of developing a standardized system in ports. Pumping systems

in all petroleum terminals are standardized, so that any ship is able to load and

unload. Thus, the same concept of standardized oil pipelines can be applied in

ballast water systems development;

b. Stations on-land can supply, with treated water, ports and vessels that must

carry clean ballast water. Gollasch S., et al. 2007. Critical review of the IMO

international convention on the management of ships ballast water and

sediments. Harmful Algae 6: 585600.

However, the authors also mention the main disadvantages of treatment facilities on

land, such as:

a. Demand of pipe connection between the treatment plants and all the berths,

and each ship would have to change its own ballast water pumping system, if

there is no possibility of using hoses to connect to the ballast tanks. The

largest ports would need multiple units to receive ballast water;

b. Delays in shipping may occur when the capacity of the ships ballast tanks

exceed the capacity of the treatment plan (including storage tanks);

c. If vessels were able to exchange ballast water at sea, the ships operators

would probably rather this option than facilities onshore, thus limiting the

economic viability of such facilities;


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d. High cost of land acquisition for implementation of storage systems;

e. The ballast water discharged by the vessel to diminish its draft while entering

into an access channel might not be treated, which may contribute to the bio-

invasion

Despite these drawbacks, the treatment on land remains a feasible alternative within

a range of options currently available to treat ballast water, provided that the criteria

for safety, environmental acceptability, technical feasibility, practical and profitable

operations are considered. Newton Narciso Pereira, Rui Carlos Botter, Hernani Luiz

Brinati and Edson Felipe Trevis. A Study of Ballast Water Treatment Applied on Iron

Ore Ports in Brazil Using Discrete Simulation. Presented at the WMU.

Despite the efficacy of these technological applications there are global concerns

about the high energy demands required to operate ballast water treatment facilities.

These huge energy consumptions would impact the environment with additional

greenhouse gas pollution as well as an economic impact due to the increase of daily

consumption of diesel or fuel oil. At the same time a lot of heat from exhaust gases

would be released inefficiently into the atmosphere.

the completion

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