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Water
Supply from Hong Kong
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| 3.4.2.1 |
Hong
Kong's freshwater resources are currently
and will in the future be shaped by a number
of forces acting on both supply and demands.
These pressures include the demand for land
in Hong Kong; development and degradation
of Mainland sources; the efficiency of the
supply infrastructure; alternatives to freshwater;
and population growth and consumer behaviour
and are described below (also see Figure
3.4a).
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| Pressures
on Supply of Freshwater |
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| 3.4.2.2 |
As
described in the preceding sections on land
use and agriculture, the demand for land
to support additional infrastructure development
for Hong Kong's growing population is intense.
Water gathering grounds are somewhat insulated
from this pressure due to their special
designation status and restricted use regulations.
Those areas within Country Parks are granted
even greater levels of protection. However,
as development proceeds in remaining natural
areas, the threat of encroachment on the
boundary of water gathering grounds will
increase. Two types of impacts are possible:
reduced yields of freshwater and/or reduced
quality of the freshwater produced. While
either impact may be offset by measures
such as improved efficiency in the collection/delivery
system or higher levels of water treatment,
these remedies will result in higher costs
and cannot compensate indefinitely for decreases
in quantity or quality.
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| 3.4.2.3 |
As
the percentage of Hong Kong's contribution
to its own freshwater supplies has dwindled,
it has purchased larger and larger quantities
from the Mainland's Dongjiang supply system.
This system, while able to meet Hong Kong's
quantity needs over the near future is subject
to quality impacts due to deforestation around
the Dongjiang, growing industrialisation and
residential use of the catchment lands, and
salt water intrusion. The system's delivery
channels are not covered and are thus vulnerable
to contamination from fertilisers and other
wastes. Although there has been no detectable
trend of contaminants in the water, turbidity
is becoming more of a problem in terms of
equipment wear and aesthetics. Although the
Guangdong Water Bureau is investing a portion
of the revenue generated from the sale of
the water in protecting the watershed, the
increasing urbanisation of southern Guangdong
and recent expressions of public concern (SCMP
1999a) suggests that continued efforts to
protect water quality, potentially including
additional treatment in Hong Kong, will be
required. In negotiating for the annual quantities
of Dongjiang water supplies to be provided
to Hong Kong beyond 2004, heightened competition
for freshwater resources from the growing
cities of Dongguan, Huizhou and Shenzhen may
be an increasingly important factor. |
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| 3.4.2.4 |
Constraints
imposed by limits on Hong Kong and Mainland
sources can be softened by the use of freshwater
alternatives where practical. Hong Kong's
seawater supply system for flushing use has
expanded rapidly in recent years. However,
given that all districts in Hong Kong (except
for Victoria Peak, Yuen Long, North District
and the outlying islands) are now supplied
with seawater for flushing purposes, most
of the benefits of using this alternative
to freshwater have already been realised.
Existing seawater abstraction plant are sensitive
to increased turbidity levels resulting from
coastal development (dredging and sewage discharges)
and marine traffic activities (eg ship wakes)
and must be shielded from adverse impacts. |
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| Pressures
on Demand for Freshwater |
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| 3.4.2.5 |
The
greatest pressure on the demand for freshwater
in Hong Kong is population growth. The recorded
decrease in per capita consumption in recent
years is most likely attributable to relocation
of industrial activities out of Hong Kong,
and thus does not necessarily reflect any
changes in consumer behaviour. Continued population
growth in the territory will act to increase
demand although the extent of this increase
will depend on whether true per capita consumption
can be reduced through household initiatives
involving water conservation, kitchen and
bathroom fittings, and/or through public education
regarding the importance of water conservation
and perhaps even water pricing. |
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| 3.4.2.6 |
Water leakage during delivery results in a
substantial loss of the overall available
volume of freshwater in Hong Kong (22.5%).
This statistic compares favourably with other
areas of Southeast Asia such as Manila where
the water supply system leakage rates are
as high as 40-50% (ADB 1996) but is not as
low as the 10% figure for urban Japan (WSD,
pers comm). In recognition of the conservation
potential of efficient delivery, WSD is scheduled
to undertake a major 20 year programme of
watermain replacement later this year (WSD
1998). |
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