ENV4-2: Oil discharges into coastal waters Brief Definition Total accidental, licensed and illegal disposal of
mineral oil into the coastal and marine
environment
Units Tonnes
Alternative Definitions None
Agenda 21 Chapter 17: Protection of the oceans, all kinds of
seas, including enclosed and semi-enclosed seas,
and coastal areas and the protection, rational use
and development of their living resources
POLICY RELEVANCE (a) Purpose: This indicator shows the amount of oil discharged into coastal waters
and the effectiveness of measures designed to reduce these discharges over time in
accordance with regional seas conventions and action plans. (b) Relevance to Sustainable Development: Coastal ecosystems provide important
economic benefits, such as fisheries, tourism and outdoor recreation. They are also
important for biodiversity, which is recognized by the Convention on Biological
Diversity (CBD). Agenda 21, based on the United Nations Convention on the Law of
the Sea (UNCLOS), advocates an integrated, ecosystem approach to protect oceans
and coastal areas.
Such an approach is heavily dependent on the application of
precautionary and anticipatory principles to maintain biodiversity and ecosystem
productivity while improving the quality of life of coastal communities.
Oil lost or discharged into the sea represents a pollution threat that can damage coastal
ecosystems, endanger marine life and pollute beaches and coastlines. Its toxic effects
can kill or damage marine organisms, and its physical effects on marine life can result
in the loss of water-repellent properties and reduced thermal insulation and buoyancy.
Furthermore, oil spills can have a considerable impact on human activities that depend
on clean seawater and clean shores, notably tourism, fishing and aquaculture.
Oil is used by the population at large and enters the marine and coastal environment
not only directly from shipping, oil drilling, etc., but also as the final sink from a large
variety of hinterland uses. Although there may be legislation to limit this
‘background’ pollution, enforcement depends heavily on the public’s understanding
of the threat, good practices and the reward of good practices. By focusing on the
input from all sources and designing suitable monitoring and reporting techniques, an
indicator can be developed that could be used for assessing policies and defining
strategies for improving the situation.
The impact of oil pollution depends on the type of oil and the sensitivity of the
specific area affected, as well as the weather and the way the cleanup is handled.
Damage to a salt marsh polluted by oil may be almost irreversible, whereas a rocky
shore can be restored with a relatively quick and satisfactory recovery programme.