EPD - Beach Water Quality


Beach Water Quality in Hong Kong 2011

Our Mission:

To safeguard the health and welfare of the community and meet conservation goals by working to achieve and maintain the Water Quality Objective for bathing beaches

[Photo: The local community and overseas tourists all enjoy very much the beautiful beaches in Hong Kong]


Many attractive beaches are found along the long coastline of Hong Kong. Each year, millions of beach-goers enjoy bathing in these beaches with clean water.

[Photo: Kid enjoying summer fun at Stanley Main Beach]

The objective of the Environmental Protection Department (EPD)'s Beach Water Quality Monitoring Programme is to monitor beach water quality and protect the health of bathers. The background and details of EPD's monitoring activities can be found at EPD’s Homepage (http://www.epd.gov.hk) or its thematic website (http://www.beachwq.gov.hk).

[Photo: Blue sky and clean water greet swimmers at Deep Water Bay Beach]

This report summarises the beach monitoring data collected in 2011, the gradings of the beaches and their compliance with the Water Quality Objective (WQO) for bathing beaches. In 2011, the EPD monitored 41 gazetted beaches and three non-gazetted beaches in different parts of the territory. The gazetted beaches were monitored weekly during the bathing season from March to October, and EPD staff made field observations and collected samples for laboratory analyses of E. coli bacteria. EPD staff also took measurements of dissolved oxygen, pH, salinity, temperature and turbidity of beach water.

[Photo: EPD inspectors monitor water quality at Lido Beach]

[Photo: Bacterial testing of beach water at EPD's laboratory]

Hong Kong's beaches are assessed using a dual system: annual ranking and weekly grading which are both based on the E. coli level in beach water to indicate potential health risks associated with swimming. The annual ranking reflects the overall water quality of the beach over the entire bathing season, while the weekly grading denotes the recent water quality of the beach. Under the dual rating system, beaches are categorised into "Good", "Fair", "Poor" and "Very Poor". Those ranked "Good" and "Fair" meet the WQO for bathing waters.

Annual Beach Ranking in 2011

All 41 gazetted beaches in Hong Kong complied with the WQO in 2011. Compared with the ranking in 2010, the number of beaches ranked as “Good” has increased from 23 (or 56%) to 31 (or 76%). The improvement was due to the progress of eight beaches from last year's ranking of “Fair” to “Good”. The remaining 10 beaches were ranked as “Fair”, and none as “Poor” or “Very Poor”.

[Photo: The scenic Trio Beach]

The beaches with a "Good" water quality ranking were largely located in the Southern District (Hong Kong Island South), Outlying Islands, Sai Kung and Tsuen Wan. All 12 beaches in the Southern District were ranked as "Good" in 2011. Of the nine beaches monitored on the Outlying Islands, eight were "Good" while Silver Mine Bay Beach was rated as "Fair". In the Sai Kung area, all six beaches were "Good" in 2011. Among them, Hap Mun Bay Beach and Trio Beach were the cleanest gazetted beaches in Hong Kong in terms of overall E. coli levels. On the western side, all six beaches along the Tuen Mun coast received a "Fair" ranking in 2011.

The water quality of the Tsuen Wan beaches has continued to show improvement in 2011, which is mainly brought about by the full commissioning of the Advance Disinfection Facilities (ADF) in March 2010 to disinfect the treated effluent from the Stonecutters Island Sewage Treatment Works, and the completion of the sewerage works in the hinderland of the beaches. Since all the Tsuen Wan beaches have achieved the WQO for bathing, four previously closed beaches, namely Approach Beach, Casam Beach, Hoi Mei Wan Beach and Lido Beach, were reopened to the public for swimming in June 2011. The Government has planned to re-open the remaining three beaches, namely Anglers' Beach, Gemini Beaches and Ting Kau Beach in the swimming season of 2013.

In 2011, Casam Beach, Hoi Mei Wan Beach, Lido Beach and Ma Wan Tung Wan Beach were ranked as "Good" while Approach Beach was ranked as "Fair".

[Photo: Hong Kong beaches offer respite from hustle and bustle of city life]

EPD also monitored three non-gazetted beaches in Hong Kong: Discovery Bay (a popular beach on Lantau Island), a sandy beach adjacent to Kiu Tsui Beach in Sai Kung, and a planned artificial beach in Lung Mei, Tai Po. Discovery Bay and the beach adjacent to Kiu Tsui Beach continued to be ranked as "Good" in 2011. Similar to 2010, Lung Mei was ranked as "Poor" in 2011. The public sewerage network is being extended to villages in the Lung Mei area, and other pollution abatement measures will be implemented to improve the water quality in the Lung Mei area in the next few years.

[Photo: Fun for all ages at Hap Mun Beach]

Weekly Beach Grading in 2011

The EPD issues weekly gradings of gazetted beaches which are open for swimming. The information is disseminated to the public through weekly press releases, EPD's websites, the beach hotline and beach noticeboards.

In 2011, the water quality of beaches in the Southern District has shown great improvement. All ten gazetted beaches received mainly "Good" or "Fair" grading in the bathing season. Chung Hom Kok, Deep Water Bay, Hairpin, South Bay, St. Stephen's, Stanley Main and Turtle Cove Beaches had the best water quality, achieving "Good" gradings on all rating occasions.

The water quality of the Sai Kung beaches was also generally good. Hap Mun Bay and Trio Beaches achieved "Good" gradings for all rating occasions, while the other beaches were mostly "Good" or "Fair".

The beaches on the Outlying Islands were generally ideal for swimming, with Cheung Chau Tung Wan, Hung Shing Yeh, Kwun Yam, Tong Fuk and Upper Cheung Sha Beaches achieving 100% "Good" gradings. Lo So Shing and Lower Cheung Sha Beaches achieved "Good" gradings over 80% of the rating occasions.

The water quality of the beaches in the Tuen Mun area was generally fine and nearly all graded as "Good" or "Fair". The water quality of Beaches in Tsuen Wan continued to show positive signs of improvement with gradings maintained mostly at either "Good" or "Fair".

[Photo: An impressive view of the Ting Kau Bridge from the Casam Beach]

Water Quality Trend

There has been a noticeable trend in the improvement of beach water quality in Hong Kong in recent years. The percentage of beaches complying with the WQO has changed from 74% in 1986 (29 of 39 beaches) to 63% (26 of 41 beaches) in 1997, and then improved to 100% in 2010 and 2011 (all 41 beaches).

Annual beach ranking of 1986, 1997 and 2011 compared


WQO Compliant

WQO Non-compliant




Very Poor







24.4% (10)

39.0% (16)

29.3% (12)

7.3% (3)






( ) No. of beaches

Note: Two Beaches degazetted in 1995 were excluded from the calculation.

There was a drop in compliance rate in the mid-1990s due to population growth particularly in the new town areas. Since then, there has been progressive improvement in the last decade as a result of enforcement of environmental legislation, extension of the sewerage network and provision of new sewage treatment facilities across the territory including the beach hinterland. Major improvement measures implemented in the past are summarized in the following table.

Major improvement measures for the beaches over the past 25 years

1986 – 1990

Implementation of the Livestock Waste Control Scheme under the Waste Disposal (Livestock Waste) Regulation.

Declaration of the Southern Water Control Zone (WCZ) under the Water Pollution Control Ordinance (WPCO) and legislative enforcement.

Interception and diversion of polluted storm drains at beaches in Southern District.

Most beaches, particularly Silver Mine Bay Beach

Southern beaches

Southern beaches

1991- 1995

Implementation of chemical waste control.

Declaration of the North Western WCZ under WPCO and legislative enforcement.
Diversion of polluted storm water drains away from Castle Peak Beach.
Provision of public sewers for So Kwun Wat and Sam Shing Estate.

Commissioning of Stanley Sewage Treatment Works (STW).

All beaches

Tuen Mun beaches

Stanley Main Beach

1996 - 2000

Full implementation of WPCO in all WCZs.

Commissioning of the Shek O Sewage Screening Plant and diversion of polluted storm water drains at Shek O Village.

Completion of all major works under Southern Southern Sewerage Master Plan.

Commissioning of the new 2 km long Pillar Point sewage submarine outfall.

All beaches

Shek O Beach

Southern beaches

Tuen Mun beaches

2001 - 2005

Completion of HATS Stage 1.

Provision of public sewers in the Silverstrand area.

Full operation of the Sham Tseng STW.

Big Wave Bay, Shek O, Rocky Bay Beaches

Silverstrand Beach

Beaches along the Tsuen Wan coast

2006 - 2010

Commissioning of the Advance Disinfection Facilities at Stonecutters Island STW.

Extension of the public sewerage network to the beach hinterland along Castle Peak Road.

All Tsuen Wan beaches

Beaches along the Tsuen Wan coast

As a result of these measures, the percentage of beaches ranked as "Good" has significantly increased over the period, rising from just 23% in 1986 to 76% in 2011. Since 1999, the WQO compliance rate has been maintained at over 80%, a clear indication of sustained improvement in water quality. Between 1997 and 2011, out of the 41 gazetted beaches, those complying with the WQO have increased from 26 to 41 (63% to 100%). In the same period, the number of "Good" beaches has more than tripled from 10 to 31. 

Compliance with WQO at gazetted beaches, 1997 - 2011

[Figure: Compliance with WQO at gazetted beaches, 1997 - 2011]

Back in the 1980s, many beaches were either closed, such as Cafeteria Old Beach, Castle Peak Beach and Silver Mine Bay Beach, or on the verge of being closed (e.g. Middle Bay Beach and Repulse Bay Beach) because of poor water quality. Through continuous efforts of the Government to implement pollution abatement measures over the past years, there were significant improvements at the beaches in various districts in the last few years. Silver Mine Bay Beach, Castle Peak Beach and Repulse Bay Beach were most remarkable as they have consistently complied with the WQO in recent years. All the seven closed Tsuen Wan beaches met the WQO in 2010 and 2011. All Hong Kong’s beaches have now achieved the required standard for bathing waters.

Water quality trend lines of individual beaches over the last 26 years are included in this report to show the changes over the years. More in-depth background and details of the beach monitoring programme are available at EPD's Homepage (http://www.epd.gov.hk) or its thematic website (http://www.beachwq.gov.hk), which provides user-friendly access to the annual beach reports as well as data published since 2000.

[Photos: Paradise for kids]

The Monitoring Programme

Beaches monitored by the EPD


Sai Kung

Tsuen Wan

Tuen Mun

Islands District

Tai Po

Deep Water Bay
Repulse Bay
Middle Bay
South Bay
Chung Hom Kok
St. Stephen's
Stanley Main
Turtle Cove
Shek O
Big Wave Bay
Rocky Bay

Kiu Tsui
Hap Mun Bay
Clear Water Bay First
Clear Water Bay Second
Kiu Tsui (New)**

Ma Wan Tung Wan
Hoi Mei Wan
Ting Kau

Castle Peak
Cafeteria Old
Cafeteria New

Silver Mine Bay
Pui O
Lower Cheung Sha
Upper Cheung Sha
Tong Fuk
Cheung Chau Tung Wan
Kwun Yam
Hung Shing Yeh
Lo So Shing
Discovery Bay**

Lung Mei**


** Non-gazetted beaches


Beach monitoring frequencies


Monitoring frequency per month

Bathing season *

Non-bathing season

Gazetted beaches open all year round**

at least 3 times

at least 3 times

Other gazetted beaches

at least 3 times


Non-gazetted beaches

at least 3 times


*  March to October

** Clear Water Bay Second, Deep Water Bay, Golden and Silverstrand Beaches


Overview of Various Stages of the Beach Monitoring Programme

[Image of overview of various stages of the Beach Monitoring Programme]


Hong Kong's annual beach ranking system


E. coli counts per 100 mL*

Minor illness rate**
(Cases per 1,000 swimmers)

WQO Compliance












Very Poor



* Geometric mean E. coli count calculated based on all data collected between March and October.

** Skin and gastrointestinal illnesses

Hong Kong's weekly beach grading system


Beach water quality

E. coli counts per 100 mL*

Minor illness rate **
(Cases per 1,000 swimmers)














Very Poor

or last reading >1,600


* Unless otherwise indicated, the E. coli count represents the geometric mean of the 5 most recent sampling occasions.

** Skin and gastrointestinal illnesses

The 2011 Findings

Hong Kong's gazetted beaches – 2011 annual ranking

Beach grading summary by district in 2011

[Image of Annual Ranking of gazetted beaches at a glance]

Southern District beaches

Sai Kung beaches

Tsuen Wan and Tuen Mun beaches

Outlying Islands beaches

Water Quality Trend

Annual beach rankings from 1997 to 2011

Annual beach ranking of 1997 and 2011 compared

Annual geometric mean E. coil levels by district, 1997-2011


Appendix A - Annual geometric mean E. coli levels (1997 – 2011)

Appendix B - 2011 beach visitor number

Appendix C - Physicochemical water quality data of gazetted beaches, 2011

Appendix D – Images of Long-term trend of beach water quality (1986 – 2011)


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