Pacific Islands Environment Outlook - UNEP

FRESH WATER 11
The biological diversity of Pacific islands is among
the most critically threatened in the world. Between
1982 and 1991 the proportion of states noting serious
biodiversity loss rose from 67 to 75 per cent, according
to an ADB survey. Islands of this region now have more
threatened species (110) than any other.
Biodiversity in the region is pressurized by largescale
forest logging, commercial agriculture, associated
land clearing, and fires. Population pressure has led to
shifting cultivation being intensified and marginal forest
lands and other habitats depleted. Large-scale mining in
some countries (e.g. Nauru) has destroyed whole
ecosystems. Land-based sources of marine pollution (for
example eroded soils, pesticides, heavy metals, nitrates
and chlorinated hydrocarbons) are considered to be one
of the four greatest threats to marine biodiversity, along
with habitat destruction/degradation (including
dynamiting), overexploitation of living resources and
invasive species.
As the economies of most PICs are still subsistence
based, most Pacific islanders are dependent on local
biological and other natural resources for survival. In the
Pacific islands, biodiversity conservation is much more
than an economic and an ecological issue, it is also a
social and cultural one.
Fresh water
Developments over the past 100 years
Compared to most developed countries there are
relatively few long-term data within the region on
historical levels of water quality or quantity. As in other
areas (such as Africa) there has been a post-colonial
decline in the level and continuity of monitoring activity.
Except in some urban areas, on most islands piped water
supply systems and water storage systems such as water
tanks and reservoirs are a very recent development.
There is no doubt that occasional water shortages have
historically been a problem throughout the Pacific,
especially during drier than normal years. The most
severe water shortages would have been experienced on
the atolls and raised limestone islands, where there are
no rivers and inhabitants must rely on the groundwater
lens floating on top of the salt water. The ability of the
smaller atolls to sustain an exploitable freshwater lens
has determined whether these islands have been able to
sustain permanent habitation or not. However, there has
been this rather romantic notion that, throughout the
coastal areas of Pacific islands, water supplies are
supplemented by the ubiquitous coconut tree, which
provides drinking water when other water supplies are in
poor supply or unavailable. These areas have never
sustained populations of any size or for any length of
time (SOPAC 1999).
Developments over the past 10 years
During the 1980s the UN Water Decade helped address
a great many of the regional concerns in the water and
sanitation sector. One resulting success was the
instigation of a regional mechanism focusing on capacity
building, sharing technology, co-ordination and
avoidance of duplication of effort. At the end of the
decade, regional and subregional reports, by WHO and
UNDP in particular, provided the first comprehensive
region-wide review and synthesis of the situation
(UNDP 1996). Figure 1.3 gives an overview.
Water-related issues were also reported as a major
problem in 1992 (Thistlethwaite and Votaw 1992), with
two-thirds of SPREP members noting problems of
supply/storage and an even higher number reporting
groundwater pollution. More specifically PNG did not at
that time register water shortage as a priority, but would
now need to register the effects of recent drought. In
Samoa there is concern about the excessively high
consumption of water as a result of the inefficient use of
water supplies and supply leakage. The region-wide
drought in 1998 and the resulting water shortages have
highlighted the urgency for Samoans and others to reduce
water consumption. Detailed work has not yet been
carried out on groundwater pollution levels but the
statistics on waste flows (see Atmosphere section, below)
show that the pressures are building up, especially in
urban areas and on the atolls and low-lying islands. Waste
disposal systems (both solid and liquid) are still generally
inadequate in the Pacific islands and this problem is likely
to continue to worsen as populations increase (Loerzel
1998a; SPREP 1999b).
Fresh water resources and their management give
rise to many different problems in the region. In the high
islands, despite high levels of total rainfall, water is
sometimes not available where and when it is needed due
to the seasonality of the rainfall. Localized pollution,
excessive sedimentation due to uncontrolled watershed
development and water wastage are common problems
reported by Fiji, Samoa and Solomon Islands. In some
atoll communities where water shortages may force
people to use polluted groundwater for drinking and
cooking, health problems such as diarrhoea and hepatitis
are prevalent, with occasional outbreaks of typhoid, and,
in Kiribati, Tuvalu and the Marshall Islands, even rare