Beach Water quality
Weekly Beach Grading in 2009
The beach has mostly achieved Grades 1 and 2 during a bathing season, while occasionally it hovers to Grade 3 and 4.
Behind the beach is the Tai Long Wan Village where a number of village houses are present. Due to the lack of sewerage system around the area, sewage from these domestic premises is treated by septic tanks and soak-away pits. During heavy rainfall, effluent may occasionally surcharge from these systems and increase the amount polluted surface-water runoff, thus it may lead to deterioration of the water quality of the beach.
The current Beach Monitoring Programme has been designed to assess the water quality of bathing beaches and the compliance with the WQO. The beach monitoring data would also provide information on beach water quality trends for the authority to decide on whether a beach should be opened or closed for swimming. The monitoring of beach water quality is based on the measurement of E. coli density which is the microbiological parameter stipulated in the WQO and is also an internationally acceptable indicator.
The establishment of an annual ranking system facilitates the interpretation of long term water quality changes at different beaches. The rank of a beach is determined by calculating the annual geometric mean E. coli density with all the data collected during the bathing season from 1 March to 31 October.
Under the annual ranking system, beaches are classified according to their annual geometric mean E. coli densities in the beach water. There are four categories for the annual ranking of beaches, viz. "Good", "Fair", "Poor" and "Very Poor". The water quality of beaches in the first two categories i.e. "Good" and "Fair", meets the WQO for bathing beaches. Beaches having annual geometric mean E. coli densities greater than 610 per 100mL are ranked "Very Poor" and Leisure and Cultural Services Department would consider closing these beaches for the next bathing season.
|Fair||25 - 180|| 10|
|Poor||181 - 610||11 to 15||Not complied|
|Very Poor||> 610||> 15|
* Geometric mean E. coli count calculated based on all the data collected during the bathing season.
** Gastrointestinal and skin complaints