Risk Assessment in Ballast Water Management - Global Maritime Transport and Ballast Water Management: Issues and Solutions - page 162

- the ballast water is from a donor port that contains HAO that are already present

in the recipient port and also occur in a similar abundance, where these are not
under any control program.

The ballast water will be deemed as posing a high risk in conditions when:

- there is no reliable data about environmental (i.e., salinity) or biological condi-

tions in the donor port; or

- the ballast water is from a donor port that contains HAO (i.e., non-indigenous

species and toxic algae (not in the blooming state), which are not present in the
recipient port).

The RA will result in an extreme risk in conditions when:

- the ballast water is from a donor port that contains target species, especially

when those occur in much higher abundance as in the recipient port;

- the ballast water is from a donor port that contains toxic algae that are in a bloom

state;

- the ballast water is from a donor port that contains human pathogens; or

- the ballast water is from a donor port that contains HAO that are already present

in the recipient port, where these are under any control program in the donor
port.

The BWRA model to assess the level of risk posed by ballast water to the recipi-
ent port is shown in Fig. 6 . According to each level of risk identifi ed different BWM
measures may be applied (see chapter “ Ballast Water Management Decision Support
System ”).

Implementation of Selective Ballast Water Management
Based on Risk Assessment

The advantages of the blanket approach include low data and skill requirements and
it is simple for port State implementation. However, the main disadvantages are that
more burden is placed on ship crews with “unnecessary” BWM requirements (in
case of low risk), which will result in more costs for the shipping industry. Depending
on the BWM method used also more pressures may be placed on the environment
(e.g., in case chemical treatment of ballast water is required which may result in
residual toxic components in discharged ballast water or in the addition of neutral-
ization agents before ballast water discharge).
The selective approach places less “unnecessary” BWM burden on vessels, but it
requires more extensive data gathering for port States as well as more data and
reporting requirements for vessels. It may require higher skills and knowledge for
port State personnel; however with an appropriate decision support system (DSS)
this can be overcome.