3. Over 90% of all global trade, including
everything from food and fuel to construction
materials, chemicals , Gas, Grain,Bulk
household items is carried by ships, with over
50,000 merchant ships sailing the worlds
oceans, with a combined tonnage of over 1.6
billion DWT.
It is estimated that some 3 – 5 billion t of
ballast water is transferred throughout the
world each year.
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4. 1 m³ of ballast water may contain up to 50,000
zooplankton specimens. Thousands of different
marine species small enough to pass through a
ship’s ballast water intake ports & pumps.
It is estimated that 7,000 to 10,000 different
species of marine microbes, plants and animals are
transferred globally through BW annually.
At the same time, BW may contain
considerable amount of sediments. Once settle
down in the tanks, provides a substrate for a
variety of marine species.
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6. Grows & spreads very fast
Displaces native algae
Alters local eco system
Alters food chain
Effects local fish & shellfish stocks
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8. Reproduces rapidly.
Feeds excessively on zooplankton.
Depletes zooplankton stocks; altering food
web and ecosystem function.
Contributed significantly to collapse of
Black and Asov Sea fisheries in 1990s, with
massive economic and social impact.
Now threatens similar impact in Caspian
Sea.
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10. The BWM Convention was entered into
force 12 months after the date on which not less
than 30 States, the combined merchant fleets of
which constitute not less than 35% of the GT of
the world’s merchant ships, had signed it.
Convention was in force since September 2017
Applies to all ship with few exclusions
such as war ships, vessels not going out of a
party’s waters etc.
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14. Ballast water Ballast water exchange standard D1
Ships performing ballast water exchange shall do
so with an efficiency of 95% of ballast water.
For ships exchanging ballast water by the flow-
through method, pumping through three times the
volume of each ballast water tank will be
considered to meet the standard described.
Pumping through less than three times the
volume may be accepted provided the ship could
demonstrate that at least 95% exchange is met.
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15. Ballast water treatment equipment
Many companies have developed and are
marketing equipment to treat ballast water to meet
the D2 standard.
This equipment typically employs filtration
followed by treatment via UV radiation or an
oxidizing biocide before discharge.
There are at least 50 companies with formal
approval from the IMO. The USCG provided
temporary approval for a number of treatment
systems for use in USA waters and is embarking
on more detailed approval procedure.
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