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BEAM PLUS FOR EXISTING BUILDINGS WATER USE (WU)
V ERSION 1.2
Copyright © 2012 BEAM Society Limited. All rights reserved.
Page 88
5 WATER USE 5.P PREREQUISITE
5.1
5.2
INTRODUCTION Water is known to be in scarce supply in many parts of the world, even
though it is also in surplus elsewhere. Globally, water conservation is
already a major issue [1]. Hong Kong has long enjoyed a reliable and
economic supply of most of its fresh water needs from the Mainland.
However, with increased industrialisation of Guangdong Province there
is likely to be greater competition for water supply, meaning that water
conservation may become a significant issue for Hong Kong in the
future.
Hong Kong should look into ways to improve the utilisation and
conservation of water resources.
5.P PREREQUISITES WU P1 WATER QUALITY S URVEY
WU P2 MINIMUM WATER SAVING PERFORMANCE
WU P3 WATER CONSERVATION PLAN
BACKGROUND In Hong Kong, the WSD controls water quality, such as taste, odour,
hardness, sediment, pH, the quantity of dissolved iron, etc., in order to
provide water that meets the Guidelines for Drinking-water Quality
recommended by Samples are
taken at treatment works, service reservoirs, consumer taps and
analysed at site and at WSD’s laboratories. Nevertheless, the
unsatisfactory quality of potable water delivered at taps may be due to
the corrosion of water pipes or the cleanliness of water tanks. As a
consequence the use of bottled water is common, but is not considered
to be an environmentally preferred solution due to the production and
transport requirements. To ensure the health of building users, designers
need to ensure optimal potable water quality at the tap - potable water
that is both safe and acceptable in terms of taste, colour and odour.
It is also necessary to reduce the potable water consumption. This can
be achieved through the application of water saving fixtures and the use
of non-potable water (e.g. harvested rainwater and recycled grey water)
and implementation of a water conservation plan.
5.1 WATER
CONSERVATION
WU 1 ANNUAL WATER USE
WU 2 MONITORING AND CONTROLS
WU 3 WATER USE FOR IRRIGATION
WU 4 WATER RECYCLING
WU 5 WATER AUDIT
WATER SUPPLY Except for a small number of villages scattered in the remotest areas,
over 99.9 per cent of Hong Kong’s population receives piped fresh water
supply of purity that, according to WSD, is among the best to be found
anywhere. Sea water is supplied to about 80 per cent of the population
for toilet flushing, though mains fresh water is supplied to areas that are
not close to the seafront, or where the population is scattered and
sparse. Raw water from the Dongjiang River in Guangdong continues to
be Hong Kong’s main source of supply and makes up about 70-80 per
cent of Hong Kong’s needs.
In 2007 the average daily consumption of fresh water was 2.61 million
1 OECD. Environmental Performance Reviews - Water. Performance and Challenges in OECD Countries. 2003.