The water quality of 34 out of
41 gazetted beaches had met the water quality
objectives for bathing water in 2001. The year
2001 had been a wet year with exceptional heavy
rain during the summer months, breaking the monthly
rainfall record for June and exceeded the normal
range for the bathing season by 40%. Heavy rain
would flush pollutants in the beach hinterland
into beaches causing temporary deterioration of
water quality. As a result of the heavy downpour,
the percentage of beaches meeting the Water Quality
Objective (WQO) has slightly dropped from 85%
in 2000 to 83% in 2001 (Figure I). Among the 41
gazetted beaches, 21 are ranked 'Good', 13 'Fair',
five 'Poor' and two 'Very Poor' (Figure II).
The distribution of annual
ranks for gazetted beaches in the past ten years
is shown in Figure III. The improving water
quality trend observed in the late 1990's had
stalled in 2001.
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| Figure
III Distribution of annual
ranks for gazetted beaches for the past
10 years |
The gazetted beaches on the
south of Hong Kong Island and the outlying islands
such as Lamma Island and Cheung Chau had consistently
good water quality. Their weekly grading, which
were determined using results of the last five
sampling occasions, also indicated their consistently
good water quality throughout the bathing season.
The effect of heavy rain on the water quality
of these beaches was not significant.
Beaches with more fluctuations
of their water quality and weekly grading were
found in the Tsuen Wan District. As the hinterland
of these beaches was still unsewered, their
water quality was highly susceptible to the
effect of rain. Apart from the rainfall effect,
the water quality of these beaches was also
affected by the polluted Sham Tseng Nullah,
and to a small extent by the polluted marine
water around the Rambler Channel. Therefore,
the water quality of the gazetted beaches along
the Tsuen Wan coastal strip was "Poor"
or "Very Poor" in 2001.
For the non-gazetted beaches,
seven of the nine beaches monitored met the
WQO for bathing water. The annual ranks of all
the non-gazetted beaches monitored by EPD were
shown in Figure IV.
With the progressive completion
of the sewerage improvement works along the
Tsuen Wan coastal strip and for the Sham Tseng
area in the next few years, it is envisaged
that the water quality of the Tsuen Wan beaches
will improve.
 |
| Figure IV Annual
ranking of non-gazetted beaches in 2001 |
|