Port and Harbour Operations
Potential issues, key processes & potential
Potential impacts on marine SACs
Possible means of avoiding, minimising and
Issue: Maintenance wastes and runoff
Key process: Toxic contamination
Potential impact: Wastes from the
cleaning of port and harbour infrastructure
and boat/ship maintenance areas can contain
harmful contaminants that may have toxic effects
on marine wildlife. Cleaning agents include
biocides, bleach, and detergents. The combined
effects of these substances needs further
Bleach and other chlorine containing chemicals
used to clean harbour structures may have
toxic effects on shellfish and fish, and reduce
the diversity of marine wildlife in localised
The use of detergents for cleaning operations
can form phosphate-rich waters that may encourage
the formation of algal blooms which can cause
oxygen depletion and may result in the localised
suffocation of animals.
The effects depend on scale of maintenance
operations, background water quality, maintenance
techniques used, amounts/types of contaminant
in wastes and proximity of marine features.
Impacts are likely to be localised and temporary
due to dilution, however there may be more
of a problem in enclosed areas or areas with
low tidal flushing.
Cleaning agents tend to only be a problem
when used in high concentrations and often
present the only effective means of ensuring
safety in harbour areas.
Educate, encourage and train harbour staff.
Raise public awareness of environmental management
Ensure staff follow good housekeeping practices.
Provide separate collection facilities for
Consider constructing bunds, sumps and/or
installing oily separators to collect wash
down wastes and reduce contaminants entering
the harbour where necessary.
Use environmentally sensitive alternatives
to biocides or harmful cleaning agents wherever
Where no suitable effective alternative is
available, minimise amounts used and frequency
of use where practical.
Give high priority to finding effective alternatives
so that the use of substances containing phosphates
and chlorine can be stopped.
Issue: Anti-fouling paints
Key process: Toxic contamination
Potential impact: Most anti-fouling
paints are toxic. When allowed to accumulate
in high concentrations in sediments they can
be toxic to non-target marine organisms. The
adverse effects of TBT on marine life are
well known, particularly with regard to shellfish
and molluscs. Copper-based anti-fouling paints
are less toxic to non-target species, but
may still have toxic effects in high concentrations.
The use of TBT anti-fouling paints on commercial
vessels is at present the most effective option
available. However, the IMO have recently
decided to ban the use of TBT in antifouling
paints. Research and development is ongoing
to find and test alternative coatings. Copper
anti-fouling paints have been relatively widely
used on vessels and are the BPEO available
to the marine industry at present. Toxic effects
from copper to non-target species are only
likely as a result of high amounts in sediments
due to continued spills or careless maintenance
operations. Non-toxic alternatives are also
available, but are less effective.
Develop guidance to encourage the careful
use, handling, storage and disposal of antifouling
paints in the harbour.
Provide separate reception facilities for
vessel maintenance wastes.
Provide ‘scrub-off’ facilities
to collect maintenance residues from boat
Consider the use of alternative
anti-fouling agents, bearing in mind their
effectiveness and operational efficiency.