River Water Quality in Hong Kong in 2006

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Environmental Protection Department The Government of the Hong Kong Special Administrative Region

Mission To conduct an effective, scientific water monitoring programme that will help achieve and maintain the Water Quality Objectives and protect the health of Hong Kong’s rivers and streams.

Disclaimer Whilst the Government of the Hong Kong Special Administrative Region ("the Government") endeavours to ensure the accuracy of the information in this report, the Government (including its officers and employees) makes no warranty, statement or representation, expressed or implied, with respect to accuracy, completeness, or usefulness of the information contained herein, and in so far as permitted by law, shall not have any legal liability or responsibility (including liability for negligence) for any loss, damage, injury and death which may result, whether directly or indirectly, from the supply or use of such information. Users are responsible for making their own assessments of all information contained in this publication before acting on it.

Copyright Notice The information contained in this publication can be used freely for study, research and training purposes subject to acknowledgement of the source. Use of the information for purposes other than those stated above requires prior written permission of the Director of Environmental Protection.

Acknowledgement We acknowledge the contribution of the Government Laboratory for undertaking chemical analyses of the water samples. Content

1. An overview of Hong Kong’s rivers in 2006

2. Eastern New Territories rivers

3. Northwestern New Territories rivers

4. Lantau Island rivers

5. Southwestern New Territories and Kowloon rivers

Appendices

Appendix A Summary of river water quality monitoring stations and sampling A-1 frequencies in 2006

Appendix B River water quality parameters and methods of analysis B-1 B-2

Appendix C Key Water Quality Objectives (WQOs) for the rivers in the Eastern C-1 New Territories Key Water Quality Objectives (WQOs) for the rivers in the C-2 Northwestern New Territories Key Water Quality Objectives (WQOs) for the rivers in the Lantau C-3 Island Key Water Quality Objectives (WQOs) for the rivers in the C-4 Southwestern New Territories and Kowloon

Appendix D Summary of water quality monitoring data for Shing Mun River D-1 (Main Channel and Siu Lek Yuen Nullah) in 2006 Summary of water quality monitoring data for Shing Mun River (Fo D-2 Tan Nullah and Kwun Yam Shan Stream) in 2006 Summary of water quality monitoring data for Shing Mun River (Tai D-3 Wai Nullah and Tin Sum Nullah) in 2006 Summary of water quality monitoring data for Lam Tsuen River in D-4 2006 D-5 D-6 Summary of water quality monitoring data for Tai Po Kau Stream, D-7 Shan Liu Stream and Tung Tze Stream in 2006 Summary of water quality monitoring data for Ho Chung River in D-8 2006 Summary of water quality monitoring data for Sha Kok Mei River in D-9 2006

River Water Quality in Hong Kong in 2006 1 Summary of water quality monitoring data for Tai Chung Hau Stream D-10 in 2006 Summary of water quality monitoring data for Tseng Lan Shue D-11 Stream in 2006 Summary of water quality monitoring data for River Indus in 2006 D-12 Summary of water quality monitoring data for River Beas in 2006 D-13 Summary of water quality monitoring data for River Ganges in 2006 D-14 Summary of water quality monitoring data for Yuen Long Creek in D-15 2006 D-16 Summary of water quality monitoring data for Kam Tin River in 2006 D-17 Summary of water quality monitoring data for Tin Shui Wai Nullah D-18 and Fairview Park Nullah in 2006 Summary of water quality monitoring data for Ha Pak Nai Stream, D-19 Pak Nai Stream and Sheung Pak Nai Stream in 2006 Summary of water quality monitoring data for Ngau Hom Sha Stream, D-20 Tai Shui Hang Stream and Tsang Kok Stream in 2006 Summary of water quality monitoring data for Mui Wo River in 2006 D-21 D-22 Summary of water quality monitoring data for Tung Chung River in D-23 2006 Summary of water quality monitoring data for Tuen Mun River in D-24 2006 D-25 Summary of water quality monitoring data for Pai Min Kok Stream D-26 and Kau Wa Keng Stream in 2006 Summary of water quality monitoring data for Sam Dip Tam Stream D-27 in 2006 Summary of water quality monitoring data for Kai Tak Nullah in 2006 D-28 D-29

Appendix E Compliance with the river Water Quality Objectives in 2006 E-1

Appendix F Water Quality Index gradings and E. coli levels in Shing Mun River F-1 Water Quality Index gradings and E. coli levels in Lam Tsuen River F-2 and Tai Po River Water Quality Index gradings and E. coli levels in Tai Po Kau Stream, F-3 Shan Liu Stream and Tung Tze Stream Water Quality Index gradings and E. coli levels in Ho Chung River, F-4 Tai Chung Hau Stream and Sha Kok Mei Stream Water Quality Index gradings and E. coli levels in Tseng Lan Shue F-5 Stream Water Quality Index gradings and E. coli levels in River Indus, River F-6 Beas and River Ganges Water Quality Index gradings and E. coli levels in Yuen Long Creek, F-7 Kam Tin River, Tin Shui Wai Nullah and Fairview Park Nullah Water Quality Index gradings and E. coli levels in Ha Pak Nai F-8 Stream, Tai Shui Hang Stream, Pak Nai Stream, Sheung Pak Nai Stream, Ngau Hom Sha Stream and Tsang Kok Stream Water Quality Index gradings and E. coli levels in Mui Wo River F-9

River Water Quality in Hong Kong in 2006 2 Water Quality Index gradings and E. coli levels in Tung Chung River F-10 Water Quality Index gradings and E. coli levels in Tuen Mun River F-11 Water Quality Index gradings and E. coli levels in Pai Min Kok F-12 Stream, Sam Dip Tam Stream and Kau Wa Keng Stream Water Quality Index gradings and E. coli levels in Kai Tak Nullah F-13

Appendix G Water quality trends for Shing Mun River (Main Channel, Siu Lek G-1 Yuen Nullah and Fo Tan Nullah) as analysed by the Seasonal Kendall Test Water quality trends for Shing Mun River (Kwun Yam Shan Stream, G-2 Tai Wai Nullah and Tin Sum Nullah) as analysed by the Seasonal Kendall Test Water quality trends for Lam Tsuen River and Tai Po River as G-3 analysed by the Seasonal Kendall Test Water quality trends for Tai Po Kau Stream, Shan Liu Stream and G-4 Tung Tze Stream as analysed by the Seasonal Kendall Test Water quality trends for Ho Chung River, Sha Kok Mei Stream and G-5 Tai Chung Hau Stream as analysed by the Seasonal Kendall Test Water quality trends for Tseng Lan Shue Stream as analysed by the G-6 Seasonal Kendall Test Water quality trends for River Indus, River Beas and River Ganges as G-7 analysed by the Seasonal Kendall Test Water quality trends for Yuen Long Creek, Kam Tin River, Tin Shui G-8 Wai Nullah and Fairview Park Nullah as analysed by the Seasonal Kendall Test Water quality trends for Ha Pak Nai Stream, Pak Nai Stream, Sheung G-9 Pak Nai Stream, Ngau Hom Sha Stream, Tai Shui Hang Stream and Tsang Kok Stream as analysed by the Seasonal Kendall Test Water quality trends for Mui Wo River as analysed by the Seasonal G-10 Kendall Test Water quality trends for Tung Chung River as analysed by the G-11 Seasonal Kendall Test Water quality trends for Tuen Mun River as analysed by the Seasonal G-12 Kendall Test Water quality trends for Pai Min Kok Stream, Sam Dip Tam Stream G-13 and Kau Wa Keng Stream as analysed by the Seasonal Kendall Test Water quality trends for Kai Tak Nullah as analysed by the Seasonal G-14 Kendall Test

River Water Quality in Hong Kong in 2006 3 1. An overview of Hong Kong’s rivers in 2006

Hong Kong’s steep terrain and high summer rainfall result in many rivers, streams and water channels, particularly in the New Territories. It is crucial to keep these waterways clean and free from pollution to protect people’s health and the aquatic ecosystem. The Environmental Protect- ion Department (EPD) has implemented a comprehensive monitoring programme for rivers in Hong Kong since 1986. The objectives are to determine the health of waterways, reveal long-term changes in water quality, assess compliance with the statutory Water Quality Objectives, and provide the basis for implementing water pollution control work. Few city dwellers know that beautiful streams such as Tseng Lan Shue Stream in Tseung Kwan O exist

The Tung Chung River in Lantau Island has been well preserved.

River Water Quality in Hong Kong in 2006 4

Map of river monitoring stations and Water Quality Index gradings in 2006

SHENZHEN Water Quality Index N Excellent Good 11 Fair 12

Bad 13 Inland watercourses Very Bad 1. Tseng Lan Shue Stream 14 10 2. Ho Chung River 9 3. Tai Chung Hau Stream 4. Sha Kok Mei Stream 17 15 8 16 5. Shing Mun River 18 - Shing Mun Main Channel - Fo Tan Nullah 19 7 - Siu Lek Yuen Nullah 6 20 - Kwun Yam Shan Stream 23 - Tai Wai Nullah 21 NEW TERRITORIES -Tin Sum Nullah 22 4 6. Tai Po Kau Stream 24 7. Tai Po River 25 26 5 3 8. Lam Tsuen River 9. Tung Tze Stream 10. Shan Liu Stream 11. River Ganges 2 12. River Indus 27 13. River Beas 14. Fairview Park Nullah 28 KOWLOON 15. Kam Tin River 1 16. Yuen Long Creek 17. Tin Shui Wai Nullah 18. Ngau Hom Sha Stream 19. Sheung Pak Nai Stream 20. Pak Nai Stream 21. Ha Pak Nai Stream HONG KONG 22. Tai Shui Hang Stream 23. Tsang Kok Stream 30 ISLAND 29 24. Tuen Mun River LANTAU 25. Pai Min Kok (Anglers’) Stream ISLAND 26. Sam Dip Tam Stream 27. Kau Wa Keng Stream 28. Kai Tak Nullah 29. Mui Wo River 22o10’ N 30. Tung Chung River

In 2006, the number of stations monitored monthly totaled 82, covering 30 rivers and streams. The monitoring involved making field measurements and collecting water samples for laboratory analyses of over 40 parameters, including physico-chemical characteristics, organics, nutrients, toxic metals and bacteria.

The overall water quality of Hong Kong rivers in 2006 continued to improve. In terms of compliance with the statutory Water Quality Objectives (WQOs), the compliance rate in 2006 was at a record high of 86%, up from 85% in 2005 and 76% in 1997. This was the result of the implementation of various pollution abatement schemes, including the Livestock Waste Control Scheme, the Water Pollution Control Ordinance and Sewage Master Plans.

River Water Quality in Hong Kong in 2006 5

WQO compliance in the inland waters of Hong Kong, 1986 - 2006

100

90 86 85 83 83 82 82 82 80 78 77 76

72 70 70 68 66

61 61 62 60 WQO Compliance 58

(By percentage % of monitoring stations) monitoring of % percentage (By 50 49 49 47

40 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 Year

A similar trend was observed in the Water Quality Index (WQI) grading, which reflects the general health of rivers. In 2006, 81% of river monitoring stations were ‘Excellent’ or ‘Good’ as compared to 68% in 1997. Out of these, a record number of 58% of the stations was graded ‘Excellent’, further advanced from the 51% in 2005. The majority of the monitoring stations in the Lantau Island, Eastern New Territories, Southwestern New Territories and Kowloon were in these categories. At the other end of the scale, 14% of the monitoring stations were graded ‘Bad’ or ‘Very Bad’ in 2006. These watercourses were mainly found in the Northwestern New Territories where most livestock farms and unsewered villages are located.

Water Quality Index gradings for the inland waters of Hong Kong,

1986 – 2006

Year 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 (Total num ber of (47) (54) (57) (68) (76) (75)(75) (86) (86) (86) (86) (82) (82) (81) (82) (82) (82)(82) (82) (82) (82) monitoring stations)

37.2 38.5 33.8 47.4 43.6 2.7 50.0 51.3 57.7 28.4 46.1 46.1 35.0 37.7 32.4 Excellent 19.7 9.5 8.5 18.4

9.3 12.7 43.3 25.5 29.7 23.0 Good 22.4 30.8 28.2 31.2 18.4 18.2 22.1 16.7 14.3 22.1 26.9 21.8 30.8 29.5 30.8 29.5 23.1

Fair 21.3 20.4 20.6 21.1 21.1 20.3 20.8 23.0 18.9 18.2 16.9 17.9 18.2 16.7 15.4 16.7 12.8 9.0 6.4 5.1 5.1

9.0 10.3 14.3 14.8 13.0 13.0 12.8 11.7 11.5 11.5 14.1 14.1 12.8 10.3 19.2 17.1 18.9 18.9 Bad 22.2 23.7 6.4

Water Quality Index 25.4 5.1 1.3 1.3 3.8 10.4 2.5 1.3 2.6 10.8 11.7

(By percentage (By percentage stations) % of monitoring 14.3 16.2 25.0 13.1 21.6 Very Bad 25.5

31.4 27.0

River Water Quality in Hong Kong in 2006 6

Compared with 2005, rivers with stations that have improved from ‘Good’ to ‘Excellent’ in 2006 included Pai Min Kok Stream, Sam Dip Tam Stream, River Indus, Kai Tak Nullah, Lam Tsuen River, and Shing Mun River. On the other hand, two monitoring stations on Yuen Long Creek and Kam Tin River deteriorated from ‘Bad’ to ‘Very Bad’.

2. Eastern New Territories rivers

Ten rivers and streams in three Water Control Zones (WCZ) are monitored in the Eastern New Territories. Six are located in the Tolo Harbour and Channel WCZ: Shing Mun River, Lam Tsuen River, Tai Po River, Tai Po Kau Stream, Shan Liu Stream and Tung Tze Stream. Within the Port Shelter WCZ, Ho Chung River, Sha Kok Mei Stream and Tai Chung Hau Stream enter Sai Kung Hoi. Tseng Lan Shue Stream is the only watercourse within the Junk Bay WCZ.

The Eastern New Territories has the best river and stream water quality in the territory. In 2006, the overall WQO compliance of rivers was 95%, up from 93% in 2005 and 86% in 1997. Among the major rivers in the Tolo Harbour WCZ, Shing Mun River has shown a significant improvement from 78% compliance in 1997 to 94% in Ho Chung River has excellent’ water quality like many 2006 and the Lam Tsuen River other rivers in the eastern New Territories. compliance rate rose from 88% to 95% during the same period. Ho Chung River in the Port Shelter WCZ has achieved full (i.e. 100%) compliance in 2006; whereas the compliance rate for Tseng Lan Shue Stream rose steadily from 79% in 1997 to 90% compliance over the last 10 years.

As for the WQI grading, 97% of the monitoring stations in 2006 were graded ‘Good’ or above; those receiving an ‘Excellent’ grading increased from 56% to 75% over the last 10

River Water Quality in Hong Kong in 2006 7 years, and none of the stations was in the ‘Bad’ or ‘Very Bad’ category. The improvements were due to the continued enforcement of the Water Pollution Control Ordinance, the implementation of the Tolo Harbour Sewerage Master Plan Stage 1 and the Port Shelter Sewerage Master Plan Stages 1 and 2, and connection of village houses to public sewer. As sewerage works continue in the area, the water quality of the rivers is likely to improve further in the coming years.

Water Quality Index gradings for rivers in the Eastern New Territories, 1997 and 2006 1997 2006 (Overall WQO compliance rate: 86%) (Overall WQO compliance rate: 95%)

Fair Fair Good 3% 16% 22%

Good Excellent 56% 28% Excellent 75%

3. Northwestern New Territories rivers

In the Northwestern New Territories, the EPD monitors a total of 13 rivers and streams flowing into the Shenzhen River or directly into Deep Bay (Shenzhen Bay). Three of these—the Rivers Indus, Beas and Ganges—are major rivers situated in the North District. The Yuen Long Creek, Kam Tin River, Tin Shui Wai Nullah and Fairview Park Nullah are situated in A minor stream in Lau Fau Shan as seen on a summer’s day. Yuen Long, while six minor streams are located around Lau Fau Shan.

The water quality of the minor streams around Lau Fau Shan was high in 2006, with a WQO compliance between 88% and 100%, and 83% of the stations reached an ‘Excellent’ WQI grading. For the seven major rivers, the WQO compliance rates were much lower, ranging

River Water Quality in Hong Kong in 2006 8 from 33% to 78%. However, apart from the Yuen Long Creek (which had the lowest WQO compliance rate), all other rivers have shown an improvement in water quality since 1997, particularly the Rivers Beas, Indus and Ganges in the North District. The E. coli bacteria content of the major rivers was very high at hundreds of thousands to millions per 100 millilitres.

Compliance with the Water Quality Objectives in the major rivers of North District and

Yuen Long in 1997 and 2006

Compliance in 1997 (%) Compliance in 2006 (%)

46 River Indus 73 38 River Beas 78 41 River Ganges 62 33 Yuen Long Creek 33 27 Kam Tin River 39 69 Tin Shui Wai Nullah 76 32 Fairview Park Nullah 45

Currently, pollution of the major rivers in the Northwestern New Territories remains serious because of pollution from livestock farms and unsewered villages in the area. With the implementation of the new Voluntary Surrender of Poultry and Pig Farm Licence Schemes where participating farms are required to close down by the end of 2007, livestock waste pollution should reduce significantly. Under the North District Sewerage Master Plan and Yuen Long & Kam Tin Sewerage Master Plan, most of the unsewered villages will be provided with public sewers by 2015. River water quality in the Northwestern New Territories is expected to improve as these schemes take effect.

4. Lantau Island rivers

Lantau Island is less densely populated than other areas in Hong Kong. Here, two major rivers with eight monitoring stations are monitored by the EPD: Mui Wo River on the south-eastern side of the island, and Tung Chung on the north-western side. In the 1990s, the livestock farm pollution around Mui Wo River was drastically reduced under the Livestock Waste Control Scheme, bringing an immediate improvement to the water quality.

River Water Quality in Hong Kong in 2006 9

With only a few unsewered villages present in the river catchments, both Mui Wo River and Tung Chung River consistently displayed a highly satisfactory water quality. In 2006, the WQO compliance of both rivers stood at 99%, with 88% of the monitoring stations achieving an ‘Excellent’ WQI grade and the remaining 12% of the stations in the ‘Good’ grade, similar to that in 2005. However, the levels of E. coli bacteria at two Upstream view of Mui Wo River in 2006 with of the stations, TC3 and MW5 were high pristine water flowing. (6400 cfu/100mL), indicating the effects of local pollution from village houses.

Compliance with the Water Quality Objectives in the rivers of Lantau Island in 1997 and

2006

Compliance in 1997 (%) Compliance in 2006 (%)

96 Mui Wo Riv er 99

Tung Chung River 100 99

5. Southwestern New Territories and Kowloon rivers

The Southwestern New Territories and Kowloon area runs from west of Tuen Mun to the east side of Kowloon. Of the five watercourses monitored, Tuen Mun River is in Tuen Mun, Pai Min Kok Stream and Sam Dip Tam Stream are near Tsuen Wan, Kau Wa Keng Stream is in Kwai Chung and the Kai Tak Nullah is located in Kowloon. There has been a substantial improvement in the water quality of these urban watercourses in the last decade. In 2006, a total of 88% of monitoring stations reached an ‘Excellent’ or ‘Good’ grading; whereas in 1997, only 55% of the stations were ‘Good’ and none was ‘Excellent’. It is worth noting that two stations in Pai Min Kok Stream and three in Kai Tak Nullah have improved to

River Water Quality in Hong Kong in 2006 10 ‘Excellent’ in 2006. The stations with ‘Bad’ water quality grading in 1997 also showed a significant decrease from 17% in 1997 to 6% in 2006. Similarly, the overall WQO compliance of the rivers and streams in 2006 has risen to 91% from 88% in 2005 and 75% in 1997.

Water Quality Index gradings for rivers in the Southwestern New Territories and

Kowloon, 1997 and 2006 1997 2006 (Overall WQO compliance rate: 75%) (Overall WQO compliance rate: 91%)

Bad Fair Bad 17% 6% 6%

Good Good Excellent Fair 55% 33% 55% 28%

Of all the water courses in the area, Pai Min Kok Stream was least impacted by pollution and sustained a satisfactory water quality with high WQO compliance in the past 10 years. However, due to contamination from nearby unsewered premises, the E. coli level in the stream remained high, above 20,000 cfu/100mL in 2006. The source of faecal pollution will be removed when public sewers are extended to the area by 2009.

Compliance with the Water Quality Objectives in the rivers of the Southwestern New Territories

in 1997 and in 2006

Compliance in 1997 (%) Compliance in 2006 (%)

62 Tuen Mun River 85 94 Pai Min Kok Stream 94 86 Sam Dip Tam Stream 99 78 Kau Wa Keng Stream 90

* Kai Tak Nullah is a storm drain and no WQOs apply.

River Water Quality in Hong Kong in 2006 11 All remaining watercourses, particularly Tuen Mun River, have made significant progress in the last decade. Its WQO compliance rate rose steadily from 62% in 1997 to 85% in 2006. This was attributed to the enforcement of the Water Pollution Control Ordinance and implementation of the Tuen Mun Sewerage Master Plan and its Review,

The Tuen Mun River made a steady which had also led to the re-opening of Castle improvement from 1997 to 2006. Peak Beach in the downstream coastal area.

The Kai Tak Nullah’s catchment includes some of the most densely populated areas of San Po Kong, Diamond Hill, Tsz Wan Shan, Wong Tai Sin and Kowloon City. It suffered severe pollution in the 1980s and 1990s when all six monitoring stations recorded ‘Bad’ or ‘Very Bad’ water quality. Since the implementation of the East Kowloon and North and South Kowloon Sewerage Master Plans, systematic elimination of expedient connections, and exporting of treated effluent from the Sha Tin and Tai Po Sewage Treatment Works which enhanced flushing in the nullah, the water quality has shown a dramatic improvement. In 2006, five of the six water stations achieved an ‘Excellent’ WQI grading, and the most downstream station, KT1, was graded ‘Fair’. Once a black and foul-smelling open drain, Kai Tak Nullah is now teeming with fish again.

River Water Quality in Hong Kong in 2006 12 Appendix A

Summary of river water quality monitoring stations and sampling frequencies in 2006

No. of Monitoring Area Watercourse Monitoring Station Stations (Sampling frequency) Eastern New Territories Shing Mun River Shing Mun Main Channel TR19I 1 (monthly) Siu Lek Yuen Nullah TR23A, TR23L 2 (monthly) Sha Tin Fo Tan Nullah TR17, TR17L 2 (monthly) Kwun Yam Shan Stream KY1 1 (monthly) Tai Wai Nullah TR19, TR19A, TR19C 3 (monthly) Tin Sum Nullah TR20B 1 (monthly) TR12, TR12B, TR12C, Tai Po Town Lam Tsuen River TR12D, TR12E, TR12F, 9 (monthly) Centre TR12G, TR12H, TR12I Tai Po River TR13 1 (monthly) Tai Po Kau Stream TR14 1 (monthly) Tai Po Rural Shan Liu Stream TR4 1 (monthly) Area Tung Tze Stream TR6 1 (monthly) Ho Chung River PR1, PR2 2 (monthly) Sai Kung Sha Kok Mei Stream PR5, PR6 2 (monthly) Tai Chung Hau Stream PR7, PR8 2 (monthly) Tseung Kwan O Tseng Lan Shue Stream JR3, JR6, JR11 3 (monthly) Northwestern New Territories River Indus (Ng Tung River) IN1, IN2, IN3 3 (monthly) North District River Beas (Sheung Yue River) RB1, RB2, RB3 3 (monthly) River Ganges (Ping Yuen River) GR1, GR2, GR3 3 (monthly) Yuen Long Creek YL1, YL2, YL3, YL4 4 (monthly) Kam Tin River KT1, KT2 2 (monthly) Yuen Long Tin Shui Wai Nullah TSR1, TSR2 2 (monthly) Fairview Park Nullah FVR1 1 (monthly) Ha Pak Nai Stream DB1 1 (monthly) Tai Shui Hang Stream DB2 1 (monthly) Pak Nai Stream DB3 1 (monthly) Lau Fau Shan Sheung Pak Nai Stream DB5 1 (monthly) Ngau Hom Sha Stream DB6 1 (monthly) Tseng Kok Stream DB8 1 (monthly) Lantau Island Mui Wo Mui Wo River MW1, MW2, MW3, MW4, MW5 5 (monthly) Tung Chung Tung Chung River TC1, TC2, TC3 3 (monthly) Southwestern New Territories and Kowloon Tuen Mun Tuen Mun River TN1, TN2, TN3, TN4, TN5, TN6 6 (monthly) Pai Min Kok (Anglers’) Stream AN1, AN2 2 (monthly) Tsuen Wan and Sam Dip Tam Stream TW1, TW2, TW3 3 (monthly) Kwai Chung Kau Wa Keng Stream KW3 1 (monthly) KN1, KN4, KN5, KN7 4 (monthly) Kowloon Kai Tak Nullah KN2, KN3 2 (quarterly) Total 30 - 82

River Water Quality in Hong Kong in 2006 A - 1 Appendix B

River water quality parameters and methods of analysis

Water Quality Reporting Limit Analytical Method1 / Analyst Parameter and Unit Physical Chemical Properties Water temperature 0.1 °C Dissolved Oxygen 0.1 mg/L, 1% Multi-parameter water quality data logger, model YSI-6820 / On-site pH 0.1 measurement / EPD Conductivity 1 µS/cm Turbidity 0.1 NTU Electromagnetic flow meter, model Flo-mate 2000 / On-site Flow 1 L/s measurement / EPD Solid Contents In-house method GL-PH-23, based on APHA2 20ed 2540 D / Suspended Solids 0.5 mg/L Government Laboratory In-house method GL-PH-19, based on APHA 20ed 2540 B / Total Solids 0.5 mg/L Government Laboratory In-house method GL-PH-19, based on APHA 20ed 2540 E / Total Volatile Solids 0.5 mg/L Government Laboratory Aggregate Organics 5-Day Biochemical Oxygen Demand 1 mg/L In-house method based on APHA 18ed 5210 B / EPD

(BOD5) Chemical Oxygen In-house method GL-OR-38 & GL-OR-39, based on ASTM3 D1252-00 2 mg/L Demand (COD) A & B (CODCr ) / Government Laboratory Total Organic Carbon In-house method GL-OR-32, based on APHA 20ed 5310 B / 1 mg/L (TOC) Government Laboratory Faecal Bacteria E. coli 1 cfu /100 mL In-house method4, membrane filtration with CHROMagar Liquid ECC Faecal Coliforms 1 cfu / 100 mL medium / EPD Nutrients In-house method GL-IN-15, based on ASTM D3590-89 B (FIA) / Ammonia-Nitrogen 0.005 mg/L Government Laboratory In-house method GL-IN-18, based on APHA 20ed 4500-NO - B (FIA) / Nitrite-Nitrogen 0.002 mg/L 2 Government Laboratory In-house method GL-IN-18, based on APHA 20ed 4500-NO - F & I Nitrate-Nitrogen 0.002 mg/L 3 (FIA) / Government Laboratory In-house method GL-IN-14 & GL-IN-15, based on ASTM D3590-89 B Total Kjeldahl Nitrogen 0.05 mg/L (FIA) & APHA 20ed 4500-N A&D (FIA) / Government Laboratory Ortho-phosphate as In-house method GL-IN-16, based on ASTM D515-88 A (FIA) / 0.002 mg/L Phosphorus Government Laboratory In-house method GL-IN-14 & GL-IN-16, based on ASTM D515-88 B Total Phosphorus 0.02 mg/L (FIA) & APHA 20ed 4500-P G (FIA) / Government Laboratory Molybdate-Reactive In-house method GL-IN-17, based on APHA 20ed 4500-SiO2 C&E 0.05 mg/L Silica (FIA) / Government Laboratory Reference notes: 1. Mention of brand names of commercial products does not constitute or imply endorsement or recommendation by the Environmental Protection Department. 2. APHA - American Public Health Association: Standard Methods for the Examination of Water and Wastewater. 3. ASTM - Annual Book of American Society for the Testing and Materials Standards, Vol. 11.01 & 11.02. 4. i) Ho, B.S.W. and Tam, T.Y. (1997). Enumeration of E. coli in environmental waters and wastewater using a chromogenic medium. Wat. Sci. Tech., 35, 409-413. ii) DoE and DHSS (1983). “The bacteriological examination of drinking water supplies 1982. Report on Public Health and Medical Subjects No. 71. Methods for the Examination of Waters and Associated Materials”. Department of Environment, Department of Health and Social Security, Public Health Laboratory Service, H.M.S.O. London.

River Water Quality in Hong Kong in 2006 B - 1

Appendix B

River water quality parameters and the methods used for their analysis

Water Quality Reporting Limit Analytical Method1 / Analyst Parameter and Unit Metals Aluminium 50 µg/L Antimony 1 µg/L Arsenic 1 µg/L Barium 1 µg/L Beryllium 1 µg/L Boron 50 µg/L Cadmium 0.1 µg/L Chromium 1 µg/L Copper 1 µg/L In-house method GL-TE-63, based on USEPA Method 6020A Iron 50 µg/L (ICP-MS) / Government Laboratory Lead 1 µg/L Manganese 10 µg/L Mercury 1 µg/L Molybdenum 2 µg/L Nickel 1 µg/L Silver 1 µg/L Thallium 1 µg/L Vanadium 2 µg/L Zinc 10 µg/L Industrial and Commercial Pollutants In-house method GL-IN-42, based on ASTM D4374-00 (FIA, Cyanide 0.01 mg/L amperometric) / Government Laboratory In-house method GL-IN-47, based on APHA 20ed 4500-F- C & G (Ion Fluoride 0.2 mg/L Selective Electrode) and ASTM D1179-99 B (FIA) / Government Laboratory In-house method GL-OR-30, based on BS 6068, Section 2.23 (1986) Anionic Surfactants (Colorimetric) & In-house method GL-OR-27, based on Abbott, D.C. 0.05 mg/L (as Manoxol OT) “Analyst”, Vol.87, p.286(1962) & S. Motomizu et al., “Analyst” Vol.113, p.747(1988) (FIA) / Government Laboratory In-house method GL-OR-26, based on APHA 20ed 5520 C (IR) / Oil and Grease 0.5 mg/L Government Laboratory Sulphide Contents Free Hydrogen Sulphide 0.01 mg/L In-house method GL-IN-46, based on APHA 20ed 4500S2- D Sulphide 0.02 mg/L (Colorimetric) / Government Laboratory Plant Pigments Chlorophyll-a 0.2 µg/L In house method GL-OR-34, based on APHA 20ed 10200H 2 Pheo-Pigment 0.2 µg/L (spectrophotometric) / Government Laboratory Reference notes: 1. Mention of brand names of commercial products does not constitute or imply endorsement or recommendation by the Environmental Protection Department. 2. APHA - American Public Health Association: Standard Methods for the Examination of Water and Wastewater. 3. ASTM - Annual Book of American Society for the Testing and Materials Standards, Vol. 11.01 & 11.02.

River Water Quality in Hong Kong in 2006 B - 2

Appendix C

Key Water Quality Objectives (WQOs) for river monitoring stations in the Eastern New Territories

Key Water Quality Objective Maximum Maximum Maximum 5-Day Annual Minimum Monitoring Chemical Watercourse Biochemical Median Dissolved station pH range Oxygen Oxygen Suspended Oxygen Demand Demand Solids (mg/L) (mg/L) (mg/L) (mg/L) Tolo Harbour and Channel Water Control Zone KY1 6.5 - 8.5 3 15 20 4 TR17 6.5 - 8.5 5 30 20 4 TR17L 6.5 - 8.5 5 30 20 4 TR19 6.5 - 8.5 5 30 20 4 TR19A 6.5 - 8.5 5 30 20 4 Shing Mun River TR19C 6.5 - 8.5 5 30 20 4 TR19I 6.0 - 9.0 5 30 25 4 TR20B 6.5 - 8.5 5 30 20 4 TR23A 6.5 - 8.5 3 15 20 4 TR23L 6.5 - 8.5 3 15 20 4 TR12 6.5 - 8.5 3 15 20 4 TR12B 6.5 - 8.5 3 15 20 4 TR12C 6.5 - 8.5 3 15 20 4 TR12D 6.5 - 8.5 3 15 20 4 Lam Tsuen River TR12E 6.5 - 8.5 3 15 20 4 TR12F 6.5 - 8.5 3 15 20 4 TR12G 6.5 - 8.5 3 15 20 4 TR12H 6.5 - 8.5 3 15 20 4 TR12I 6.0 - 9.0 5 30 25 4 Tai Po River TR13 6.5 - 8.5 5 30 20 4 Tai Po Kau Stream TR14 6.0 - 9.0 5 30 25 4 Shan Liu Stream TR4 6.0 - 9.0 5 30 25 4 Tung Tze Stream TR6 6.0 - 9.0 5 30 25 4 Port Shelter Water Control Zone PR1 6.5 - 8.5 5 30 25 4 Ho Chung River PR2 6.5 - 8.5 5 30 25 4 PR5 6.0 - 9.0 5 30 25 4 Sha Kok Mei Stream PR6 6.0 - 9.0 5 30 25 4 PR7 6.0 - 9.0 5 30 25 4 Tai Chung Hau Stream PR8 6.0 - 9.0 5 30 25 4 Junk Bay Water Control Zone JR3 6.0 - 9.0 5 30 25 4 Tseng Lan Shue Stream JR6 6.0 - 9.0 5 30 25 4 JR11 6.0 - 9.0 5 30 25 4

* The WQO compliance for suspended solids is based on annual median value, while WQO compliance for other parameters is based on individual measurements.

River Water Quality in Hong Kong in 2006 C - 1

Appendix C

Key Water Quality Objectives (WQOs) for river monitoring stations in the Northwestern New Territories

Key Water Quality Objective Maximum Maximum Maximum 5-Day Annual Minimum Monitoring Chemical Watercourse Biochemical Median Dissolved station pH range Oxygen Oxgyen Suspended Oxygen Demand Demand Solids (mg/L) (mg/L) (mg/L) (mg/L) Deep Bay Water Control Zone IN1 6.5 - 8.5 3 15 20 4 River Indus IN2 6.5 - 8.5 3 15 20 4 IN3 6.5 - 8.5 3 15 20 4 RB1 6.5 - 8.5 3 15 20 4 River Beas RB2 6.5 - 8.5 3 15 20 4 RB3 6.5 - 8.5 3 15 20 4 GR1 6.5 - 8.5 3 15 20 4 River Ganges GR2 6.5 - 8.5 3 15 20 4 GR3 6.5 - 8.5 3 15 20 4 YL1 6.5 - 8.5 3 15 20 4 YL2 6.5 - 8.5 3 15 20 4 Yuen Long Creek YL3 6.5 - 8.5 5 30 20 4 YL4 6.5 - 8.5 5 30 20 4 KT1 6.5 - 8.5 3 15 20 4 Kam Tin River KT2 6.5 - 8.5 3 15 20 4 TSR1 6.0 - 9.0 5 30 20 4 Tin Shui Wai Nullah TSR2 6.0 - 9.0 5 30 20 4 Fairview Park Nullah FVR1 6.0 - 9.0 5 30 20 4 Ha Pak Nai Stream DB1 6.0 - 9.0 5 30 20 4 Tai Shui Hang Stream DB2 6.0 - 9.0 5 30 20 4 Pak Nai Stream DB3 6.0 - 9.0 5 30 20 4 Sheung Pak Nai Stream DB5 6.0 - 9.0 5 30 20 4 Ngau Hom Sha Stream DB6 6.0 - 9.0 5 30 20 4 Tsang Kok Stream DB8 6.0 - 9.0 5 30 20 4

* The WQO compliance for suspended solids is based on annual median value, while WQO compliance for other parameters is based on individual measurements.

River Water Quality in Hong Kong in 2006 C - 2

Appendix C

Key Water Quality Objectives (WQOs) for river monitoring stations on Lantau Island

* The WQO compliance for suspended solids is based on annual median value, while WQO compliance for other parameters is based on individual measurements.

River Water Quality in Hong Kong in 2006 C - 3

Appendix C

Key Water Quality Objectives (WQOs) for river monitoring stations in the Southwestern New Territories and Kowloon

Key Water Quality Objective Maximum Maximum Maximum 5-Day Annual Minimum Monitoring Chemical Watercourse Biochemical Median Dissolved station pH range Oxygen Oxgyen Suspended Oxygen Demand Demand Solids (mg/L) (mg/L) (mg/L) (mg/L) North Western Water Control Zone TN1 6.0 - 9.0 5 30 25 4 TN2 6.5 - 8.5 3 15 20 4 TN3 6.0 - 9.0 5 30 25 4 Tuen Mun River TN4 6.0 - 9.0 5 30 25 4 TN5 6.0 - 9.0 5 30 25 4 TN6 6.0 - 9.0 5 30 25 4 Western Buffer Water Control Zone Pai Min Kok (Anglers') AN1 6.0 - 9.0 5 30 25 4 Stream AN2 6.0 - 9.0 5 30 25 4 Victoria Harbour Water Control Zone TW1 6.0 - 9.0 5 30 25 4 Sam Dip Tam Stream TW2 6.0 - 9.0 5 30 25 4 TW3 6.0 - 9.0 5 30 25 4 Kau Wa Keng Stream KW3 6.0 - 9.0 5 30 25 4 KN1 KN2 KN3 Kai Tak Nullah Not applicable KN4 KN5 KN7

* The WQO compliance for suspended solids is based on annual median value, while WQO compliance for other parameters is based on individual measurements.

River Water Quality in Hong Kong in 2006 C - 4

Appendix D

Summary of water quality monitoring data for Shing Mun River (Main Channel and Siu Lek Yuen Nullah) in 2006 Shing Mun Main Channel Siu Lek Yuen Nullah Parameter Unit TR19I TR23L TR23A 6.5 9.0 5.9 Dissolved oxygen mg/L (5.2 – 9.7) (7.8 – 10.2) (4.5 – 8.0) 7.8 8.6 7.7 pH (7.5 – 8.3) (8.0 – 9.0) (7.5 – 8.1) 3 2 6 Suspended solids mg/L (2 – 32) (1 – 4) (2 – 15) 5-day Biochemical 2 1 2 mg/L Oxygen Demand (1 – 6) (1 – 4) (1 – 5) Chemical Oxygen 16 5 14 mg/L Demand (5 – 22) (2 – 12) (3 – 21) 0.5 0.5 0.5 Oil & grease mg/L (0.5 – 0.5) (0.5 – 0.5) (0.5 – 0.5) cfu/ 9,200 23,000 63,000 Faecal coliforms 100mL (810 – 170,000) (5,000 – 220,000) (7,500 – 510,000) cfu/ 930 550 7,900 E. coli 100mL (80 – 11,000) (100 – 4,300) (390 – 300,000) 0.14 0.03 0.22 Ammonia-nitrogen mg/L (0.09 – 0.31) (0.01 – 1.80) (0.10 – 1.30) 0.11 0.22 0.36 Nitrate-nitrogen mg/L (0.01 – 0.72) (0.08 – 0.51) (0.14 – 0.91) Total Kjeldahl 0.42 0.20 0.53 mg/L nitrogen, SP (0.30 – 0.67) (0.09 – 2.20) (0.23 – 1.80) 0.01 0.02 0.04 Ortho-phosphate mg/L (0.01 – 0.03) (0.01 – 7.60) (0.01 – 0.14) Total phosphorus, 0.05 0.03 0.07 mg/L SP (0.02 – 0.07) (0.02 – 7.80) (0.04 – 0.21) 0.02 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.02) (0.02 – 0.02) (0.02 – 0.02) 50 50 80 Aluminium µg/L (50 – 150) (50 – 260) (50 – 140) 0.1 0.1 0.1 Cadmium µg/L (0.1 – 0.1) (0.1 – 0.2) (0.1 – 0.1) 1 1 1 Chromium µg/L (1 – 2) (1 – 1) (1 – 1) 5 1 5 Copper µg/L (3 – 7) (1 – 7) (2 – 20) 1 1 1 Lead µg/L (1 – 1) (1 – 1) (1 – 1) 10 10 15 Zinc µg/L (10 – 20) (10 – 40) (10 – 20) 23 Flow L/s NM NM (5 – 78) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 1 Appendix D

Summary of water quality monitoring data for Shing Mun River (Fo Tan Nullah and Kwun Yam Shan Stream) in 2006 Fo Tan Nullah Kwun Yam Shan Stream Parameter Unit TR17 TR17L KY1 8.5 6.5 8.6 Dissolved oxygen mg/L (7.7 – 10.2) (3.5 – 8.4) (7.9 – 10.1) 8.0 7.6 8.0 pH (7.6 – 8.7) (7.3 – 7.9) (7.6 – 8.3) 9 5 3 Suspended solids mg/L (1 – 24) (1 – 38) (2 – 6) 5-day Biochemical 16 2 1 mg/L Oxygen Demand (1 – 50) (1 – 4) (1 – 4) Chemical Oxygen 11 15 5 mg/L Demand (5 – 48) (5 – 21) (2 – 11) 0.5 0.5 0.5 Oil & grease mg/L (0.5 – 3.2) (0.5 – 0.6) (0.5 – 0.5) cfu/ 110,000 45,000 3,100 Faecal coliforms 100mL (9,400 – 1,000,000) (1,100 – 580,000) (370 – 18,000) cfu/ 18,000 3,700 760 E. coli 100mL (1,500 – 160,000) (240 – 21,000) (190 – 2,300) 0.25 0.20 0.02 Ammonia-nitrogen mg/L (0.02 – 0.81) (0.03 – 0.32) (0.01 – 0.04) 0.33 0.21 0.47 Nitrate-nitrogen mg/L (0.01 – 0.91) (0.13 – 0.42) (0.27 – 0.76) Total Kjeldahl 1.30 0.49 0.13 mg/L nitrogen, SP (0.11 – 2.80) (0.19 – 0.69) (0.08 – 0.43) 0.03 0.02 0.10 Ortho-phosphate mg/L (0.01 – 0.17) (0.01 – 0.05) (0.08 – 0.18) Total phosphorus, 0.12 0.05 0.11 mg/L SP (0.02 – 0.31) (0.02 – 0.11) (0.09 – 0.23) 0.02 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.06) (0.02 – 0.02) (0.02 – 0.03) 80 70 50 Aluminium µg/L (50 – 250) (50 – 140) (50 – 110) 0.1 0.1 0.1 Cadmium µg/L (0.1 – 0.2) (0.1 – 0.2) (0.1 – 0.1) 1 1 1 Chromium µg/L (1 – 1) (1 – 2) (1 – 1) 3 4 2 Copper µg/L (1 – 15) (2 – 8) (1 – 3) 2 1 1 Lead µg/L (1 – 7) (1 – 2) (1 – 1) 30 10 10 Zinc µg/L (10 – 90) (10 – 30) (10 – 20) 148 4 Flow L/s NM (11 – 1,242) (1 – 39) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 2 Appendix D

Summary of water quality monitoring data for Shing Mun River (Tai Wai Nullah and Tin Sum Nullah) in 2006 Tai Wai Nullah Tin Sum Nullah Parameter Unit TR19A TR19C TR19 TR20B 8.5 8.0 8.3 8.2 Dissolved oxygen mg/L (7.7 – 9.9) (7.5 – 8.8) (7.1 – 8.8) (7.7 – 9.5) 7.7 7.4 7.7 7.8 pH (7.3 – 8.3) (7.0 – 7.7) (7.1 – 8.9) (7.0 – 8.3) 15 12 18 2 Suspended solids mg/L (6 – 350) (3 – 110) (4 – 110) (1 – 39) 5-day Biochemical 1 2 3 1 mg/L Oxygen Demand (1 – 2) (1 – 5) (1 – 35) (1 – 2) Chemical Oxygen 9 13 11 3 mg/L Demand (4 – 14) (6 – 22) (2 – 51) (2 – 6) 0.5 0.5 0.5 0.5 Oil & grease mg/L (0.5 – 0.7) (0.5 – 0.6) (0.5 – 1.3) (0.5 – 0.5) cfu/ 210 7,700 57,000 1 Faecal coliforms 100mL (2 – 58,000) (290 – 200,000) (7,100 – 380,000) (1 – 12) cfu/ 130 550 7,600 1 E. coli 100mL (1 – 45,000) (13 – 22,000) (410 – 200,000) (1 – 4) 0.19 0.13 0.08 0.03 Ammonia-nitrogen mg/L (0.08 – 0.34) (0.05 – 0.19) (0.05 – 0.18) (0.01 – 0.09) 1.25 1.05 0.95 0.97 Nitrate-nitrogen mg/L (0.61 – 1.80) (0.59 – 2.10) (0.68 – 1.20) (0.41 – 1.60) Total Kjeldahl 0.51 0.46 0.61 0.21 mg/L nitrogen, SP (0.37 – 0.67) (0.27 – 1.40) (0.27 – 1.50) (0.10 – 0.32) 0.01 0.01 0.01 0.01 Ortho-phosphate mg/L (0.01 – 0.02) (0.01 – 0.02) (0.01 – 0.08) (0.01 – 0.04) Total phosphorus, 0.05 0.09 0.10 0.02 mg/L SP (0.02 – 0.37) (0.03 – 0.50) (0.04 – 0.49) (0.02 – 0.06) 0.02 0.02 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.02) (0.02 – 0.02) (0.02 – 0.02) (0.02 – 0.02) 190 155 145 130 Aluminium µg/L (80 – 310) (80 – 330) (110 – 990) (50 – 2,200) 3.9 1.4 0.8 0.1 Cadmium µg/L (0.9 – 14.0) (0.5 – 2.6) (0.3 – 1.7) (0.1 – 0.3) 1 1 1 1 Chromium µg/L (1 – 4) (1 – 2) (1 – 3) (1 – 3) 3 7 9 2 Copper µg/L (1 – 5) (3 – 24) (4 – 26) (1 – 7) 6 3 3 1 Lead µg/L (2 – 31) (1 – 7) (1 – 27) (1 – 4) 240 70 60 15 Zinc µg/L (60 – 1,100) (50 – 130) (40 – 230) (10 – 140) 32 115 95 54 Flow L/s (13 – 248) (51 – 540) (9 – 861) (16 – 1,360) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 3 Appendix D

Summary of water quality monitoring data for Lam Tsuen River in 2006 (Part 1 of 3)

Lam Tsuen River Parameter Unit TR12H TR12D TR12C 8.6 8.6 8.0 Dissolved oxygen mg/L (7.8 – 9.5) (8.0 – 9.3) (6.6 – 9.0) 7.3 7.3 7.4 pH (7.1 – 7.6) (6.8 – 7.6) (6.8 – 7.7) 1 1 3 Suspended solids mg/L (1 – 3) (1 – 1) (1 – 8) 5-day Biochemical 1 1 1 mg/L Oxygen Demand (1 – 1) (1 – 4) (1 – 5) Chemical Oxygen 4 2 6 mg/L Demand (2 – 6) (2 – 6) (2 – 17) 0.5 0.5 0.5 Oil & grease mg/L (0.5 – 0.5) (0.5 – 0.5) (0.5 – 0.5) cfu/ 3,600 1,700 64,000 Faecal coliforms 100mL (1,100 – 11,000) (560 – 4,800) (31,000 – 120,000) cfu/ 580 140 21,000 E. coli 100mL (230 – 3,200) (45 – 280) (6,000 – 62,000) 0.02 0.02 0.44 Ammonia-nitrogen mg/L (0.01 – 0.04) (0.01 – 0.03) (0.20 – 1.10) 0.67 0.27 1.09 Nitrate-nitrogen mg/L (0.47 – 0.99) (0.11 – 0.69) (0.57 – 1.70) Total Kjeldahl 0.10 0.06 0.80 mg/L nitrogen, SP (0.05 – 0.14) (0.05 – 0.18) (0.36 – 3.60) 0.03 0.02 0.14 Ortho-phosphate mg/L (0.02 – 0.03) (0.01 – 0.02) (0.07 – 0.28) Total phosphorus, 0.03 0.02 0.19 mg/L SP (0.03 – 0.11) (0.02 – 0.02) (0.09 – 0.40) 0.02 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.02) (0.02 – 0.02) (0.02 – 0.02) 50 50 50 Aluminium µg/L (50 – 50) (50 – 270) (50 – 100) 0.1 0.1 0.1 Cadmium µg/L (0.1 – 0.1) (0.1 – 0.1) (0.1 – 0.1) 1 1 1 Chromium µg/L (1 – 1) (1 – 1) (1 – 1) 1 1 1 Copper µg/L (1 – 2) (1 – 29) (1 – 3) 1 1 1 Lead µg/L (1 – 1) (1 – 2) (1 – 1) 10 20 10 Zinc µg/L (10 – 30) (10 – 30) (10 – 50) 116 74 232 Flow L/s (6 – 576) (12 – 1,495) (11 – 1,650) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 4 Appendix D

Summary of water quality monitoring data for Lam Tsuen River in 2006 (Part 2 of 3)

Lam Tsuen River Parameter Unit TR12G TR12F TR12B 7.8 8.6 8.7 Dissolved oxygen mg/L (6.9 – 9.0) (7.4 – 9.4) (7.7 – 9.4) 7.2 7.4 7.3 pH (6.6 – 7.4) (7.1 – 7.7) (7.0 – 7.5) 2 1 1 Suspended solids mg/L (1 – 9) (1 – 31) (1 – 2) 5-day Biochemical 1 1 1 mg/L Oxygen Demand ( 1 – 1) (1 – 1) (1 – 1) Chemical Oxygen 6 7 5 mg/L Demand (2 – 14) (2 – 12) (2 – 9) 0.5 0.5 0.5 Oil & grease mg/L (0.5 – 0.5) (0.5 – 0.5) (0.5 – 0.5) cfu/ 3,800 8,300 18,000 Faecal coliforms 100mL (1,000 – 24,000) (3,100 – 16,000) (4,100 – 1,500,000) cfu/ 200 880 820 E. coli 100mL (100 – 320) (450 – 1,600) (110 – 13,000) 0.02 0.06 0.04 Ammonia-nitrogen mg/L (0.01 – 0.04) (0.03 – 0.13) (0.03 – 0.09) 0.04 0.46 0.82 Nitrate-nitrogen mg/L (0.02 – 0.07) (0.18 – 0.65) (0.43 – 1.60) Total Kjeldahl 0.10 0.19 0.17 mg/L nitrogen, SP (0.05 – 0.17) (0.09 – 0.33) (0.11 – 0.26) 0.02 0.04 0.06 Ortho-phosphate mg/L (0.01 – 0.03) (0.03 – 0.09) (0.03 – 0.08) Total phosphorus, 0.05 0.07 0.06 mg/L SP (0.03 – 0.13) (0.04 – 0.13) (0.04 – 0.09) 0.02 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.02) (0.02 – 0.02) (0.02 – 0.02) 50 50 50 Aluminium µg/L (50 – 50) (50 – 140) (50 – 50) 0.1 0.1 0.1 Cadmium µg/L (0.1 – 0.1) (0.1 – 0.1) (0.1 – 0.1) 1 1 1 Chromium µg/L (1 – 1) (1 – 1) (1 – 1) 1 1 1 Copper µg/L (1 – 10) (1 – 2) (1 – 6) 1 1 1 Lead µg/L (1 – 1) (1 – 3) (1 – 1) 10 10 10 Zinc µg/L (10 – 50) (10 – 70) (10 – 60) 88 76 531 Flow L/s (4 – 279) (5 – 269) (158 – 2,610) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 5 Appendix D

Summary of water quality monitoring data for Lam Tsuen River (Part 3 of 3) and Tai Po River in 2006 Lam Tsuen River Tai Po River Parameter Unit TR12E TR12 TR12I TR13 8.6 8.6 5.6 8.0 Dissolved oxygen mg/L (8.0 – 9.1) (8.0 – 12.4) (3.2 – 7.5) (6.7 – 8.6) 7.7 7.3 7.3 7.4 pH (7.4 – 8.1) (7.0 – 8.9) (7.1 – 7.4) (6.5 – 7.6) 2 4 6 4 Suspended solids mg/L (1 – 5) (3 – 16) (3 – 16) (2 – 8) 5-day Biochemical 1 4 4 4 mg/L Oxygen Demand (1 – 2) (1 – 13) (2 – 15) (1 – 7) Chemical Oxygen 3 11 18 10 mg/L Demand (2 – 7) (5 – 40) (6 – 33) (2 – 21) 0.5 0.5 0.5 0.5 Oil & grease mg/L (0.5 – 0.5) (0.5 – 0.5) (0.5 – 0.5) (0.5 – 0.5) 300,000 120,000 cfu/ 7,600 23,000 Faecal coliforms (11,000 – (25,000 – 100mL (2,100 – 37,000) (2,300 – 180,000) 4,500,000) 1,000,000) cfu/ 1,800 2,900 39,000 95,000 E. coli 100mL (110 – 16,000) (440 – 130,000) (2,200 – 240,000) (9,400 – 810,000) 0.03 1.50 0.43 0.71 Ammonia-nitrogen mg/L (0.01 – 0.27) (0.23 – 9.20) (0.21 – 0.84) (0.03 – 1.90) 0.35 1.90 0.42 0.39 Nitrate-nitrogen mg/L (0.21 – 0.84) (0.73 – 5.40) (0.21 – 1.10) (0.18 – 0.71) Total Kjeldahl 0.12 2.10 0.95 1.40 mg/L nitrogen, SP (0.05 – 0.48) (0.62 – 11.00) (0.51 – 1.60) (0.12 – 2.30) 0.02 0.87 0.09 0.28 Ortho-phosphate mg/L (0.02 – 0.08) (0.12 – 1.60) (0.03 – 0.22) (0.02 – 0.47) Total phosphorus, 0.03 0.97 0.17 0.38 mg/L SP (0.02 – 0.09) (0.16 – 1.70) (0.09 – 0.36) (0.03 – 0.62) 0.02 0.02 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.02) (0.02 – 0.02) (0.02 – 0.09) (0.02 – 0.02) 50 55 50 50 Aluminium µg/L (50 – 110) (50 – 170) (50 – 90) (50 – 140) 0.1 0.1 0.1 0.1 Cadmium µg/L (0.1 – 0.1) (0.1 – 0.1) (0.1 – 0.1) (0.1 – 0.1) 1 1 1 1 Chromium µg/L (1 – 1) (1 – 1) (1 – 2) (1 – 1) 1 2 4 6 Copper µg/L (1 – 3) (1 – 26) (2 – 7) (1 – 9) 1 1 1 1 Lead µg/L (1 – 5) (1 – 2) (1 – 2) (1 – 9) 10 15 20 20 Zinc µg/L (10 – 160) (10 – 20) (10 – 80) (10 – 20) 131 123 215 Flow L/s NM (2 – 491) (16 – 356) (39 – 1,890) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 6 Appendix D

Summary of water quality monitoring data for Tai Po Kau Stream, Shan Liu Stream and Tung Tze Stream in 2006 Tai Po Kau Stream Shan Liu Stream Tung Tze Stream Parameter Unit TR14 TR4 TR6 8.2 7.3 5.8 Dissolved oxygen mg/L (7.2 – 10.2) (6.1 – 8.2) (5.0 – 8.4) 7.3 7.5 7.4 pH (7.0 – 7.7) (7.1 – 7.9) (7.1 – 8.0) 3 3 9 Suspended solids mg/L (1 – 6) (1 – 42) (2 – 35) 5-day Biochemical 1 2 2 mg/L Oxygen Demand (1 – 1) (1 – 4) (1 – 8) Chemical Oxygen 8 7 17 mg/L Demand (2 – 11) (3 – 11) (6 – 31) 0.5 0.5 0.5 Oil & grease mg/L (0.5 – 0.5) (0.5 – 0.5) (0.5 – 0.5) cfu/ 2,300 23,000 9,500 Faecal coliforms 100mL (350 – 12,000) (12,000 – 62,000) (1,000 – 190,000) cfu/ 330 4,600 3,700 E. coli 100mL (90 – 1,600) (1,200 – 16,000) (590 – 28,000) 0.04 0.40 0.40 Ammonia-nitrogen mg/L (0.02 – 0.06) (0.12 – 1.50) (0.17 – 1.80) 0.25 1.10 0.21 Nitrate-nitrogen mg/L (0.09 – 0.38) (0.56 – 2.50) (0.06 – 0.38) Total Kjeldahl 0.13 0.58 0.74 mg/L nitrogen, SP (0.06 – 0.30) (0.30 – 1.70) (0.35 – 3.10) 0.02 0.14 0.08 Ortho-phosphate mg/L (0.01 – 0.03) (0.10 – 0.27) (0.03 – 0.22) Total phosphorus, 0.03 0.18 0.12 mg/L SP (0.02 – 0.06) (0.11 – 0.37) (0.04 – 0.47) 0.02 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.02) (0.02 – 0.02) (0.02 – 0.02) 50 60 50 Aluminium µg/L (50 – 110) (50 – 140) (50 – 200) 0.1 0.1 0.1 Cadmium µg/L (0.1 – 0.2) (0.1 – 0.1) (0.1 – 0.1) 1 1 1 Chromium µg/L (1 – 1) (1 – 1) (1 – 5) 2 2 3 Copper µg/L (1 – 2) (1 – 2) (2 – 7) 1 1 1 Lead µg/L (1 – 2) (1 – 3) (1 – 4) 10 10 10 Zinc µg/L (10 – 10) (10 – 20) (10 – 20) 45 31 Flow L/s NM (5 – 333) (1 – 308) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 7 Appendix D

Summary of water quality monitoring data for Ho Chung River in 2006

Ho Chung River Parameter Unit PR1 PR2 7.8 8.4 Dissolved oxygen mg/L (5.6 – 8.4) (7.9 – 9.1) 7.2 7.5 pH (7.1 – 7.3) (7.3 – 7.8) 3 2 Suspended solids mg/L (1 – 5) (1 – 5) 5-day Biochemical 1 1 mg/L Oxygen Demand (1 – 2) (1 – 1) Chemical Oxygen 10 3 mg/L Demand (5 – 19) (2 – 6) 0.5 0.5 Oil & grease mg/L (0.5 – 0.5) (0.5 – 0.5) cfu/ 14,000 5,400 Faecal coliforms 100mL (4,600 – 49,000) (1,100 – 12,000) cfu/ 2,100 1,000 E. coli 100mL (310 – 11,000) (100 – 5,000) 0.23 0.04 Ammonia-nitrogen mg/L (0.04 – 1.30) (0.02 – 0.09) 0.31 0.31 Nitrate-nitrogen mg/L (0.18 – 0.62) (0.16 – 0.69) Total Kjeldahl 0.38 0.14 mg/L nitrogen, SP (0.13 – 1.60) (0.08 – 0.26) 0.05 0.02 Ortho-phosphate mg/L (0.02 – 0.14) (0.02 – 0.04) Total phosphorus, 0.06 0.03 mg/L SP (0.03 – 0.17) (0.02 – 0.06) 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.02) (0.02 – 0.02) 50 50 Aluminium µg/L (50 – 100) (50 – 70) 0.1 0.1 Cadmium µg/L (0.1 – 0.3) (0.1 – 0.2) 1 1 Chromium µg/L (1 – 1) (1 – 1) 2 1 Copper µg/L (1 – 3) (1 – 4) 1 1 Lead µg/L (1 – 3) (1 – 2) 10 10 Zinc µg/L (10 – 50) (10 – 20) 425 Flow L/s NM (30 – 1,200) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 8 Appendix D

Summary of water quality monitoring data for Sha Kok Mei Stream in 2006

Sha Kok Mei Stream Parameter Unit PR5 PR6 7.7 8.5 Dissolved oxygen mg/L (6.1 – 8.6) (7.9 – 10.0) 7.3 7.4 pH (6.7 – 7.8) (7.2 – 7.5) 3 4 Suspended solids mg/L (1 – 34) (1 – 20) 5-day Biochemical 2 1 mg/L Oxygen Demand (1 – 3) (1 – 2) Chemical Oxygen 6 4 mg/L Demand (2 – 11) (2 – 12) 0.5 0.5 Oil & grease mg/L (0.5 – 0.5) (0.5 – 0.5) cfu/ 28,000 9,000 Faecal coliforms 100mL (12,000 – 160,000) (3,900 – 53,000) cfu/ 8,000 1,600 E. coli 100mL (3,700 – 33,000) (200 – 21,000) 0.12 0.03 Ammonia-nitrogen mg/L (0.03 – 0.47) (0.02 – 0.12) 0.66 1.85 Nitrate-nitrogen mg/L (0.08 – 1.20) (1.50 – 2.40) Total Kjeldahl 0.38 0.22 mg/L nitrogen, SP (0.11 – 0.81) (0.10 – 0.56) 0.08 0.06 Ortho-phosphate mg/L (0.04 – 0.11) (0.05 – 0.07) Total phosphorus, 0.12 0.07 mg/L SP (0.05 – 0.17) (0.05 – 0.11) 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.02) (0.02 – 0.02) 65 50 Aluminium µg/L (50 – 140) (50 – 150) 0.1 0.1 Cadmium µg/L (0.1 – 0.1) (0.1 – 0.1) 1 1 Chromium µg/L (1 – 1) (1 – 1) 1 1 Copper µg/L (1 – 2) (1 – 10) 1 1 Lead µg/L (1 – 2) (1 – 1) 10 10 Zinc µg/L (10 – 90) (10 – 20) 132 Flow L/s NM (2 – 930) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 9 Appendix D

Summary of water quality monitoring data for Tai Chung Hau Stream in 2006

Tai Chung Hau Stream Parameter Unit PR7 PR8 8.2 7.9 Dissolved oxygen mg/L (7.9 – 10.1) (7.5 – 9.3) 7.5 7.5 pH (7.3 – 7.7) (7.0 – 7.8) 2 3 Suspended solids mg/L (1 – 9) (1 – 16) 5-day Biochemical 1 1 mg/L Oxygen Demand (1 – 2) (1 – 2) Chemical Oxygen 6 3 mg/L Demand (2 – 9) (2 – 14) 0.5 0.5 Oil & grease mg/L (0.5 – 0.5) (0.5 – 0.5) cfu/ 26,000 30,000 Faecal coliforms 100mL (7,500 – 150,000) (5,100 – 140,000) cfu/ 9,000 14,000 E. coli 100mL (2,300 – 30,000) (2,600 – 65,000) 0.08 0.06 Ammonia-nitrogen mg/L (0.03 – 0.13) (0.04 – 0.10) 0.77 1.05 Nitrate-nitrogen mg/L (0.38 – 1.00) (0.55 – 1.40) Total Kjeldahl 0.29 0.29 mg/L nitrogen, SP (0.10 – 0.42) (0.13 – 0.49) 0.05 0.06 Ortho-phosphate mg/L (0.02 – 0.07) (0.03 – 0.08) Total phosphorus, 0.06 0.07 mg/L SP (0.03 – 0.09) (0.04 – 0.12) 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.02) (0.02 – 0.02) 60 70 Aluminium µg/L (50 – 160) (50 – 190) 0.1 0.1 Cadmium µg/L (0.1 – 0.1) (0.1 – 0.1) 1 1 Chromium µg/L (1 – 1) (1 – 2) 2 2 Copper µg/L (1 – 3) (1 – 3) 1 1 Lead µg/L (1 – 2) (1 – 2) 10 10 Zinc µg/L (10 – 30) (10 – 30) 255 Flow L/s NM (48 – 1,200) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 10 Appendix D

Summary of water quality monitoring data for Tseng Lan Shue Stream in 2006

Tseng Lan Shue Stream Parameter Unit JR3 JR6 JR11 6.0 7.8 8.3 Dissolved oxygen mg/L (3.2 – 8.5) (6.1 – 9.2) (7.0 – 11.7) 7.2 7.5 7.7 pH (6.5 – 7.4) (7.1 – 7.9) (6.9 – 8.0) 4 4 2 Suspended solids mg/L (2 – 16) (1 – 14) (1 – 5) 5-day Biochemical 7 3 1 mg/L Oxygen Demand (1 – 21) (2 – 11) (1 – 8) Chemical Oxygen 21 15 8 mg/L Demand (5 – 70) (5 – 24) (4 – 13) 0.6 0.5 0.5 Oil & grease mg/L (0.5 – 1.6) (0.5 – 0.9) (0.5 – 0.5) cfu/ 74,000 100,000 9,600 Faecal coliforms 100mL (1 – 690,000) (14,000 – 900,000) (2,600 – 32,000) cfu/ 41,000 39,000 2,400 E. coli 100mL (1 – 320,000) (8,100 – 180,000) (150 – 16,000) 5.30 0.43 0.08 Ammonia-nitrogen mg/L (0.83 – 14.00) (0.17 – 1.20) (0.04 – 0.36) 1.20 3.55 3.75 Nitrate-nitrogen mg/L (0.28 – 2.10) (1.30 – 7.00) (0.96 – 7.40) Total Kjeldahl 6.55 1.45 0.45 mg/L nitrogen, SP (1.10 – 15.00) (0.64 – 2.90) (0.07 – 1.00) 0.64 1.20 0.55 Ortho-phosphate mg/L (0.16 – 1.80) (0.26 – 2.30) (0.12 – 1.20) Total phosphorus, 0.77 1.40 0.62 mg/L SP (0.20 – 2.10) (0.32 – 2.50) (0.13 – 1.20) 0.02 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.07) (0.02 – 0.02) (0.02 – 0.02) 130 80 60 Aluminium µg/L (50 – 180) (50 – 130) (50 – 110) 0.1 0.1 0.1 Cadmium µg/L (0.1 – 0.1) (0.1 – 0.1) (0.1 – 0.1) 1 1 1 Chromium µg/L (1 – 1) (1 – 1) (1 – 1) 4 4 2 Copper µg/L (2 – 6) (3 – 15) (1 – 8) 1 1 1 Lead µg/L (1 – 3) (1 – 2) (1 – 1) 20 40 10 Zinc µg/L (10 – 40) (30 – 60) (10 – 30) 90 Flow L/s NM NM (8 – 1,080) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 11 Appendix D

Summary of water quality monitoring data for River Indus in 2006

River Indus Parameter Unit IN1 IN2 IN3 3.8 7.7 8.2 Dissolved oxygen mg/L (1.6 – 7.4) (5.9 – 9.6) (7.4 – 10.1) 7.2 7.1 7.4 pH (6.6 – 7.3) (6.8 – 7.4) (6.8 – 7.6) 25 9 4 Suspended solids mg/L (7 – 88) (1 – 13) (1 – 8) 5-day Biochemical 7 2 2 mg/L Oxygen Demand (1 – 29) (1 – 9) (1 – 7) Chemical Oxygen 26 10 10 mg/L Demand (10 – 60) (2 – 16) (5 – 19) 0.5 0.5 0.5 Oil & grease mg/L (0.5 – 1.0) (0.5 – 0.5) (0.5 – 0.5) cfu/ 410,000 32,000 12,000 Faecal coliforms 100mL (46,000 – 3,700,000) (7,800 – 290,000) (1,100 – 49,000) cfu/ 140,000 4,300 4,100 E. coli 100mL (6,400 – 2,600,000) (1,500 – 21,000) (230 – 20,000) 5.35 1.04 0.39 Ammonia-nitrogen mg/L (0.31 – 21.00) (0.26 – 2.50) (0.14 – 3.60) 1.20 0.84 0.89 Nitrate-nitrogen mg/L (0.01 – 4.20) (0.59 – 1.20) (0.43 – 1.70) Total Kjeldahl 7.00 1.55 0.71 mg/L nitrogen, SP (1.20 – 24.00) (0.53 – 3.20) (0.40 – 4.00) 0.70 0.02 0.24 Ortho-phosphate mg/L (0.38 – 1.30) (0.01 – 0.06) (0.12 – 0.75) Total phosphorus, 1.04 0.18 0.37 mg/L SP (0.73 – 2.00) (0.09 – 0.25) (0.22 – 0.90) 0.02 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.39) (0.02 – 0.02) (0.02 – 0.02) 140 60 60 Aluminium µg/L (50 – 370) (50 – 140) (50 – 180) 0.1 0.1 0.1 Cadmium µg/L (0.1 – 0.2) (0.1 – 0.1) (0.1 – 0.1) 3 1 1 Chromium µg/L (1 – 15) (1 – 1) (1 – 1) 6 2 4 Copper µg/L (2 – 13) (1 –11) (2 – 10) 3 3 1 Lead µg/L (1 – 7) (2 – 7) (1 – 2) 80 1,075 20 Zinc µg/L (40 – 190) (300 – 2,200) (10 – 50) 42 Flow L/s NM NM (7 – 522) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 12 Appendix D

Summary of water quality monitoring data for River Beas in 2006

River Beas Parameter Unit RB1 RB2 RB3 8.4 7.5 8.2 Dissolved oxygen mg/L (6.5 – 9.4) (5.6 – 8.9) (2.3 – 11.1) 7.6 7.3 7.3 pH (7.3 – 8.1) (6.6 – 7.5) (6.6 – 7.6) 7 7 16 Suspended solids mg/L (1 – 65) (3 – 38) (3 – 130) 5-day Biochemical 3 4 6 mg/L Oxygen Demand (1 – 9) (1 – 51) (2 – 19) Chemical Oxygen 11 13 27 mg/L Demand (2 – 29) (2 – 90) (5 – 42) 0.5 0.5 0.5 Oil & grease mg/L (0.5 – 0.5) (0.5 – 0.8) (0.5 – 0.9) cfu/ 63,000 54,000 160,000 Faecal coliforms 100mL (27,000 – 320,000) (16,000 – 370,000) (12,000 – 2,700,000) cfu/ 22,000 27,000 42,000 E. coli 100mL (5,800 – 250,000) (8,200 – 110,000) (6,600 – 770,000) 0.42 1.56 1.65 Ammonia-nitrogen mg/L (0.11 – 3.90) (0.34 – 8.40) (0.50 – 8.30) 0.47 0.73 0.79 Nitrate-nitrogen mg/L (0.27 – 0.87) (0.01 – 0.89) (0.10 – 3.20) Total Kjeldahl 1.00 2.15 2.55 mg/L nitrogen, SP (0.43 – 5.50) (0.60 – 10.00) (1.00 – 11.00) 0.21 0.33 0.49 Ortho-phosphate mg/L (0.01 – 0.63) (0.14 – 1.60) (0.15 – 1.20) Total phosphorus, 0.34 0.58 0.83 mg/L SP (0.14 – 0.97) (0.20 – 2.30) (0.25 – 2.70) 0.02 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.05) (0.02 – 0.03) (0.02 – 0.04) 80 60 80 Aluminium µg/L (50 – 140) (50 – 120) (50 – 690) 0.1 0.1 0.1 Cadmium µg/L (0.1 – 0.1) (0.1 – 0.1) (0.1 – 0.3) 1 1 1 Chromium µg/L (1 – 1) (1 – 1) (1 – 16) 2 4 6 Copper µg/L (1 – 12) (2 – 18) (2 – 35) 1 1 2 Lead µg/L (1 – 3) (1 – 3) (1 – 10) 15 20 50 Zinc µg/L (10 – 50) (10 – 50) (20 – 210) 132 36 Flow L/s NM (29 – 425) (4 – 3,560) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 13 Appendix D

Summary of water quality monitoring data for River Ganges in 2006

River Ganges Parameter Unit GR1 GR2 GR3 6.2 4.9 7.5 Dissolved oxygen mg/L (1.7 – 8.0) (2.5 – 9.2) (6.7 – 8.5) 7.6 7.2 7.2 pH (6.8 – 8.1) (6.8 – 7.8) (6.9 – 7.5) 50 15 6 Suspended solids mg/L (23 – 660) (8 – 28) (3 – 140) 5-day Biochemical 38 9 1 mg/L Oxygen Demand (4 – 170) (4 – 53) (1 – 7) Chemical Oxygen 60 36 6 mg/L Demand (7 – 1,100) (10 – 80) (3 – 46) 1.0 1.1 0.5 Oil & grease mg/L (0.5 – 26.0) (0.6 – 11.0) (0.5 – 1.2) cfu/ 320,000 160,000 9,300 Faecal coliforms 100mL (60,000 – 1,700,000) (44,000 – 690,000) (1,900 – 280,000) cfu/ 230,000 40,000 590 E. coli 100mL (34,000 – 1,700,000) (6,100 – 600,000) (59 – 15,000) 36.00 9.45 0.14 Ammonia-nitrogen mg/L (3.10 – 210.00) (1.80 – 28.00) (0.02 – 0.52) 0.28 0.28 0.21 Nitrate-nitrogen mg/L (0.01 – 1.30) (0.01 – 0.63) (0.11 – 0.84) Total Kjeldahl 44.00 10.40 0.27 mg/L nitrogen, SP (3.50 – 300.00) (2.60 – 36.00) (0.10 – 1.90) 7.15 2.30 0.01 Ortho-phosphate mg/L (0.77 – 28.00) (0.59 – 7.80) (0.01 – 0.26) Total phosphorus, 8.60 2.90 0.02 mg/L SP (0.98 – 51.00) (0.83 – 8.40) (0.02 – 0.27) 0.06 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.22) (0.02 – 0.14) (0.02 – 0.02) 155 125 65 Aluminium µg/L (70 – 900) (50 – 220) (50 – 570) 0.1 0.1 0.1 Cadmium µg/L (0.1 – 0.2) (0.1 – 0.4) (0.1 – 0.4) 1 1 1 Chromium µg/L (1 – 6) (1 – 2) (1 – 1) 13 6 1 Copper µg/L (4 – 23) (2 – 11) (1 – 8) 2 1 1 Lead µg/L (1 – 6) (1 – 10) (1 – 12) 40 30 25 Zinc µg/L (20 – 350) (10 – 60) (10 – 200) 38 38 64 Flow L/s (14 – 171) (9 – 792) (30 – 1,035) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 14 Appendix D

Summary of water quality monitoring data for Yuen Long Creek in 2006 (Part 1 of 2)

Yuen Long Creek Parameter Unit YL1 YL2 3.6 5.7 Dissolved oxygen mg/L (2.2 – 5.3) (4.4 – 7.5) 7.4 7.5 pH (7.2 – 8.5) (7.2 – 7.7) 80 16 Suspended solids mg/L (6 – 500) (3 – 430) 5-day Biochemical 63 9 mg/L Oxygen Demand (18 – 240) (6 – 18) Chemical Oxygen 155 34 mg/L Demand (30 – 540) (16 – 310) 8.0 0.9 Oil & grease mg/L (0.5 – 37.0) (0.5 – 9.9) cfu/ 4,200,000 260,000 Faecal coliforms 100mL (1,200,000 – 8,900,000) (64,000 – 1,700,000) cfu/ 3,200,000 120,000 E. coli 100mL (930,000 – 8,500,000) (22,000 – 1,100,000) 21.50 11.50 Ammonia-nitrogen mg/L (6.40 – 52.00) (3.10 – 17.00) 0.01 3.65 Nitrate-nitrogen mg/L (0.01 – 0.63) (0.68 – 6.00) Total Kjeldahl 35.50 14.50 mg/L nitrogen, SP (8.30 – 74.00) (3.50 – 19.00) 5.35 2.35 Ortho-phosphate mg/L (1.20 – 9.60) (0.52 – 3.20) Total phosphorus, 7.00 2.90 mg/L SP (2.00 – 15.00) (0.65 – 5.80) 0.14 0.02 Sulphide, SP mg/L (0.02 – 0.53) (0.02 – 0.05) 275 190 Aluminium µg/L (80 – 3,600) (80 – 5,100) 0.1 0.1 Cadmium µg/L (0.1 – 1.0) (0.1 – 1.4) 2 1 Chromium µg/L (1 – 12) (1 – 13) 28 4 Copper µg/L (9 – 95) (2 – 92) 5 4 Lead µg/L (2 – 120) (1 – 130) 130 30 Zinc µg/L (70 – 1,400) (20 – 1,400) 254 19 Flow L/s (45 – 576) (7 – 636) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 15 Appendix D

Summary of water quality monitoring data for Yuen Long Creek in 2006 (Part 2 of 2)

Yuen Long Creek Parameter Unit YL3 YL4 2.5 3.1 Dissolved oxygen mg/L (1.2 – 5.0) (1.6 – 4.8) 7.5 7.1 pH (7.2 – 8.0) (7.0 – 7.3) 130 36 Suspended solids mg/L (7 – 980) (7 – 210) 5-day Biochemical 76 72 mg/L Oxygen Demand (17 – 350) (5 – 120) Chemical Oxygen 200 104 mg/L Demand (41 – 830) (33 – 240) 25.5 12.0 Oil & grease mg/L (2.0 – 71.0) (1.7 – 33.0) cfu/ 4,400,000 4,400,000 Faecal coliforms 100mL (1,200,000 – 13,000,000) (1,000,000 – 19,000,000) cfu/ 2,900,000 1,000,000 E. coli 100mL (1,000,000 – 8,000,000) (220,000 – 3,700,000) 21.50 4.50 Ammonia-nitrogen mg/L (4.30 – 42.00) (1.60 – 6.80) 0.01 0.01 Nitrate-nitrogen mg/L (0.01 – 0.66) (0.01 – 0.01) Total Kjeldahl 30.00 8.60 mg/L nitrogen, SP (6.40 – 60.00) (4.70 – 10.00) 3.60 0.59 Ortho-phosphate mg/L (0.73 – 6.70) (0.01 – 1.10) Total phosphorus, 5.50 1.40 mg/L SP (1.30 – 12.00) (0.66 – 1.80) 0.08 0.08 Sulphide, SP mg/L (0.02 – 0.45) (0.02 – 0.33) 285 150 Aluminium µg/L (100 – 2,900) (100 – 1,400) 0.1 0.1 Cadmium µg/L (0.1 – 0.8) (0.1 – 0.4) 1 1 Chromium µg/L (1 – 12) (1 – 4) 29 4 Copper µg/L (4 – 60) (3 – 19) 5 3 Lead µg/L (1 – 59) (1 – 25) 135 40 Zinc µg/L (20 – 830) (30 – 420) 858 138 Flow L/s (305 – 1,348) (62 – 351) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 16 Appendix D

Summary of water quality monitoring data for Kam Tin River in 2006

Kam Tin River Parameter Unit KT1 KT2 3.8 2.7 Dissolved oxygen mg/L (0.9 – 6.9) (1.1 – 6.1) 7.3 7.3 pH (7.1 – 7.5) (7.2 – 7.5) 11 40 Suspended solids mg/L (4 – 460) (9 – 140) 5-day Biochemical 12 61 mg/L Oxygen Demand (7 – 65) (11 – 120) Chemical Oxygen 33 130 mg/L Demand (12 – 570) (23 – 300) 0.7 5.5 Oil & grease mg/L (0.5 – 51.0) (0.7 – 18.0) cfu/ 670,000 1,600,000 Faecal coliforms 100mL (300,000 – 2,800,000) (250,000 – 5,300,000) cfu/ 160,000 1,200,000 E. coli 100mL (35,000 – 610,000) (130,000 – 4,300,000) 9.05 18.00 Ammonia-nitrogen mg/L (3.30 – 25.00) (4.20 – 40.00) 0.43 0.01 Nitrate-nitrogen mg/L (0.01 – 0.93) (0.01 – 0.22) Total Kjeldahl 14.50 26.00 mg/L nitrogen, SP (4.10 – 59.00) (6.50 – 69.00) 2.10 4.05 Ortho-phosphate mg/L (1.10 – 6.30) (0.95 – 7.50) Total phosphorus, 2.95 5.80 mg/L SP (1.30 – 17.00) (1.50 – 14.00) 0.07 0.04 Sulphide, SP mg/L (0.02 – 1.80) (0.02 – 0.53) 90 160 Aluminium µg/L (50 – 610) (50 – 480) 0.1 0.1 Cadmium µg/L (0.1 – 0.5) (0.1 – 0.2) 1 1 Chromium µg/L (1 – 6) (1 – 3) 9 15 Copper µg/L (2 – 18) (10 – 34) 2 4 Lead µg/L (1 – 8) (2 – 17) 40 90 Zinc µg/L (20 – 510) (40 – 230) 194 63 Flow L/s (1 – 1,121) (12 – 795) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 17 Appendix D

Summary of water quality monitoring data for Tin Shui Wai Nullah and Fairview Park Nullah in 2006 Tin Shui Wai Nullah Fairview Park Nullah Parameter Unit TSR1 TSR2 FVR1 6.0 9.9 9.2 Dissolved oxygen mg/L (1.2 – 10.6) (7.8 – 13.9) (2.9 – 13.5) 7.5 8.3 7.7 pH (6.8 – 8.4) (7.3 – 9.4) (7.3 – 8.9) 20 22 28 Suspended solids mg/L (6 – 2,000) (4 – 260) (9 – 200) 5-day Biochemical 10 2 12 mg/L Oxygen Demand (1 – 20) (1 – 5) (5 – 30) Chemical Oxygen 20 7 41 mg/L Demand (2 – 1,200) (2 – 18) (16 – 76) 0.6 0.5 0.5 Oil & grease mg/L (0.5 – 31.0) (0.5 – 1.0) (0.5 – 0.7) cfu/ 980,000 95,000 130,000 Faecal coliforms 100mL (240,000 – 16,000,000) (12,000 – 2,000,000) (45,000 – 1,200,000) cfu/ 330,000 20,000 41,000 E. coli 100mL (45,000 – 3,700,000) (2,600 – 190,000) (11,000 – 660,000) 3.15 0.16 5.90 Ammonia-nitrogen mg/L (0.18 – 12.00) (0.03 – 0.61) (2.00 – 8.20) 0.60 1.40 0.40 Nitrate-nitrogen mg/L (0.04 – 1.40) (0.51 – 1.80) (0.12 – 0.72) Total Kjeldahl 4.15 0.61 8.30 mg/L nitrogen, SP (0.34 – 50.00) (0.18 – 1.40) (3.00 – 11.00) 0.37 0.03 0.98 Ortho-phosphate mg/L (0.04 – 2.10) (0.02 – 0.10) (0.29 – 2.00) Total phosphorus, 0.64 0.07 1.35 mg/L SP (0.06 – 16.00) (0.04 – 0.18) (0.50 – 2.60) 0.02 0.02 0.02 Sulphide, SP mg/L (0.02 – 2.00) (0.02 – 0.03) (0.02 – 0.03) 145 155 165 Aluminium µg/L (80 – 460) (100 – 1,200) (70 – 330) 0.1 0.1 0.1 Cadmium µg/L (0.1 – 0.2) (0.1 – 0.1) (0.1 – 0.1) 1 1 1 Chromium µg/L (1 – 6) (1 – 2) (1 – 2) 6 2 4 Copper µg/L (1 – 19) (1 – 12) (2 – 5) 3 4 3 Lead µg/L (1 – 17) (1 – 43) (1 – 5) 65 15 20 Zinc µg/L (10 – 340) (10 – 90) (10 – 60) 59 Flow L/s NM NM (5 – 369) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 18 Appendix D

Summary of water quality monitoring data for Ha Pak Nai Stream, Pak Nai Stream and Sheung Pak Nai Stream in 2006 Ha Pak Nai Stream Pak Nai Stream Sheung Pak Nai Stream Parameter Unit DB1 DB3 DB5 8.3 8.0 8.4 Dissolved oxygen mg/L (7.6 – 9.8) (7.1 – 9.0) (7.4 – 10.0) 7.5 7.2 7.2 pH (6.8 – 8.0) (6.1 – 7.5) (6.1 – 7.6) 3 6 5 Suspended solids mg/L (1 – 42) (1 – 240) (1 – 77) 5-day Biochemical 1 1 1 mg/L Oxygen Demand (1 – 1) (1 – 3) (1 – 1) Chemical Oxygen 3 4 3 mg/L Demand (2 – 13) (2 – 22) (2 – 6) 0.5 0.5 0.5 Oil & grease mg/L (0.5 – 0.5) (0.5 – 0.5) (0.5 – 0.5) cfu/ 1,700 4,400 2,700 Faecal coliforms 100mL (360 – 7,100) (600 – 27,000) (720 – 15,000) cfu/ 130 470 190 E. coli 100mL (14 – 4,800) (80 – 3,000) (27 – 2,000) 0.02 0.03 0.02 Ammonia-nitrogen mg/L (0.01 – 0.09) (0.01 – 0.13) (0.01 – 0.03) 0.30 0.29 0.18 Nitrate-nitrogen mg/L (0.17 – 1.00) (0.19 – 0.48) (0.08 – 0.33) Total Kjeldahl 0.07 0.17 0.07 mg/L nitrogen, SP (0.05 – 0.28) (0.05 – 1.10) (0.05 – 0.18) 0.01 0.02 0.01 Ortho-phosphate mg/L (0.01 – 0.01) (0.01 – 0.11) (0.01 – 0.01) Total phosphorus, 0.02 0.06 0.02 mg/L SP (0.02 – 0.02) (0.02 – 0.22) (0.02 – 0.03) 0.02 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.02) (0.02 – 0.02) (0.02 – 0.02) 80 75 55 Aluminium µg/L (50 – 230) (50 – 420) (50 – 190) 0.1 0.1 0.1 Cadmium µg/L (0.1 – 0.1) (0.1 – 0.1) (0.1 – 0.1) 1 1 1 Chromium µg/L (1 – 1) (1 – 1) (1 – 1) 1 1 1 Copper µg/L (1 – 3) (1 – 2) (1 – 4) 1 1 1 Lead µg/L (1 – 3) (1 – 10) (1 – 7) 10 10 10 Zinc µg/L (10 – 20) (10 – 20) (10 – 130) 14 38 56 Flow L/s (2 – 86) (10 – 323) (3 – 232) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 19 Appendix D

Summary of water quality monitoring data for Ngau Hom Sha Stream, Tai Shui Hang Stream and Tsang Kok Stream in 2006 Ngau Hom Sha Stream Tai Shui Hang Stream Tsang Kok Stream Parameter Unit DB6 DB2 DB8 7.3 8.0 9.5 Dissolved oxygen mg/L (6.0 – 10.4) (7.6 – 9.2) (7.4 – 10.9) 7.0 7.4 7.9 pH (6.4 – 8.3) (6.6 – 7.8) (6.5 – 9.0) 8 4 4 Suspended solids mg/L (4 – 46) (1 – 170) (2 – 88) 5-day Biochemical 5 1 1 mg/L Oxygen Demand (1 – 13) (1 – 1) (1 – 2) Chemical Oxygen 12 3 4 mg/L Demand (4 – 59) (2 – 10) (2 – 9) 0.5 0.5 0.5 Oil & grease mg/L (0.5 – 2.1) (0.5 – 0.5) (0.5 – 0.5) cfu/ 44,000 1,700 5,400 Faecal coliforms 100mL (8,500 – 140,000) (110 – 390,000) (1,900 – 17,000) cfu/ 27,000 190 310 E. coli 100mL (5,100 – 110,000) (71 – 12,000) (31 – 3,600) 3.15 0.03 0.02 Ammonia-nitrogen mg/L (0.26 – 18.00) (0.01 – 0.06) (0.01 – 0.08) 0.61 0.17 0.25 Nitrate-nitrogen mg/L (0.17 – 1.30) (0.07 – 0.35) (0.09 – 0.98) Total Kjeldahl 4.80 0.08 0.12 mg/L nitrogen, SP (0.36 – 19.00) (0.05 – 0.51) (0.06 – 0.35) 1.50 0.01 0.01 Ortho-phosphate mg/L (0.25 – 7.80) (0.01 – 0.02) (0.01 – 0.02) Total phosphorus, 2.05 0.02 0.02 mg/L SP (0.29 – 8.00) (0.02 – 0.06) (0.02 – 0.03) 0.03 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.17) (0.02 – 0.02) (0.02 – 0.08) 75 85 120 Aluminium µg/L (50 – 140) (50 – 240) (50 – 290) 0.1 0.1 0.1 Cadmium µg/L (0.1 – 0.1) (0.1 – 0.1) (0.1 – 0.1) 1 1 1 Chromium µg/L (1 – 1) (1 – 1) (1 – 1) 6 1 1 Copper µg/L (2 – 18) (1 – 4) (1 – 2) 2 1 1 Lead µg/L (1 – 6) (1 – 42) (1 – 20) 25 10 10 Zinc µg/L (10 – 30) (10 – 50) (10 – 20) 15 95 Flow L/s NM (3 – 269) (10 – 560) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 20 Appendix D

Summary of water quality monitoring data for Mui Wo River in 2006 (Part 1 of 2)

Mui Wo River Parameter Unit MW1 MW2 MW3 8.5 8.6 8.4 Dissolved oxygen mg/L (6.9 – 10.4) (6.8 – 10.0) (7.7 – 9.6) 7.3 7.4 7.3 pH (6.9 – 7.6) (7.0 – 7.7) (6.7 – 7.7) 2 5 1 Suspended solids mg/L (1 – 9) (2 – 19) (1 – 3) 5-day Biochemical 1 1 1 mg/L Oxygen Demand (1 – 2) (1 – 3) (1 – 1) Chemical Oxygen 6 11 3 mg/L Demand (2 – 22) (4 – 26) (2 – 9) 0.5 0.5 0.5 Oil & grease mg/L (0.5 – 0.5) (0.5 – 0.5) (0.5 – 0.5) cfu/ 11,000 24,000 3,400 Faecal coliforms 100mL (610 – 190,000) (5,600 – 180,000) (530 – 34,000) cfu/ 1,600 3,600 240 E. coli 100mL (65 – 24,000) (1,000 – 19,000) (30 – 4,800) 0.04 0.31 0.02 Ammonia-nitrogen mg/L (0.02 – 0.21) (0.05 – 0.71) (0.01 – 0.04) 0.33 0.17 0.39 Nitrate-nitrogen mg/L (0.15 – 0.70) (0.12 – 0.30) (0.21 – 0.77) Total Kjeldahl 0.20 0.58 0.11 mg/L nitrogen, SP (0.10 – 0.55) (0.17 – 0.95) (0.07 – 0.32) 0.13 0.09 0.06 Ortho-phosphate mg/L (0.04 – 0.19) (0.03 – 0.15) (0.02 – 0.09) Total phosphorus, 0.15 0.14 0.08 mg/L SP (0.04 – 0.24) (0.05 – 0.30) (0.03 – 0.13) 0.02 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.02) (0.02 – 0.02) (0.02 – 0.02) 50 60 55 Aluminium µg/L (50 – 170) (50 – 140) (50 – 150) 0.1 0.1 0.1 Cadmium µg/L (0.1 – 0.1) (0.1 – 0.1) (0.1 – 0.1) 1 1 1 Chromium µg/L (1 – 2) (1 – 2) (1 – 1) 1 2 1 Copper µg/L (1 – 5) (1 – 5) (1 – 3) 1 1 1 Lead µg/L (1 – 1) (1 – 5) (1 – 1) 10 10 10 Zinc µg/L (10 – 40) (10 – 20) (10 – 40) 25 32 Flow L/s NM (6 – 4,880) (6 – 1,590) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 21 Appendix D

Summary of water quality monitoring data for Mui Wo River in 2006 (Part 2 of 2)

Mui Wo River Parameter Unit MW4 MW5 7.5 7.4 Dissolved oxygen mg/L (6.1 – 8.6) (6.2 – 9.2) 7.0 7.0 pH (6.8 – 7.8) (6.5 – 7.2) 12 5 Suspended solids mg/L (2 – 24) (3 – 74) 5-day Biochemical 1 1 mg/L Oxygen Demand (1 – 2) (1 – 4) Chemical Oxygen 12 12 mg/L Demand (4 – 31) (3 – 26) 0.5 0.5 Oil & grease mg/L (0.5 – 0.5) (0.5 – 0.5) cfu/ 5,300 35,000 Faecal coliforms 100mL (640 – 120,000) (13,000 – 170,000) cfu/ 950 6,400 E. coli 100mL (190 – 14,000) (940 – 41,000) 0.26 0.56 Ammonia-nitrogen mg/L (0.09 – 0.51) (0.09 – 2.90) 0.22 0.18 Nitrate-nitrogen mg/L (0.15 – 0.70) (0.10 – 0.43) Total Kjeldahl 0.49 0.99 mg/L nitrogen, SP (0.23 – 1.30) (0.20 – 3.30) 0.07 0.08 Ortho-phosphate mg/L (0.03 – 0.10) (0.04 – 0.18) Total phosphorus, 0.10 0.20 mg/L SP (0.08 – 0.15) (0.04 – 0.37) 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.02) (0.02 – 0.02) 70 65 Aluminium µg/L (50 – 170) (50 – 270) 0.1 0.1 Cadmium µg/L (0.1 – 0.4) (0.1 – 0.4) 1 1 Chromium µg/L (1 – 2) (1 – 1) 3 1 Copper µg/L (1 – 9) (1 – 2) 1 1 Lead µg/L (1 – 4) (1 – 12) 10 20 Zinc µg/L (10 – 40) (10 – 30) 240 60 Flow L/s (100 – 280) (24 – 624) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 22 Appendix D

Summary of water quality monitoring data for Tung Chung River in 2006

Tung Chung River Parameter Unit TC1 TC2 TC3 7.2 8.2 8.5 Dissolved oxygen mg/L (4.7 – 8.2) (7.2 – 10.1) (7.4 – 9.6) 7.0 7.6 7.7 pH (6.4 – 7.6) (6.3 – 9.2) (6.7 – 8.1) 1 2 2 Suspended solids mg/L (1 – 5) (1 – 52) (1 – 10) 5-day Biochemical 1 1 1 mg/L Oxygen Demand (1 – 1) (1 – 1) (1 – 7) Chemical Oxygen 3 6 5 mg/L Demand (2 – 15) (2 – 13) (2 – 15) 0.5 0.5 0.5 Oil & grease mg/L (0.5 – 0.5) (0.5 – 0.5) (0.5 – 0.5) cfu/ 1,200 3,600 17,000 Faecal coliforms 100mL (250 – 28,000) (380 – 63,000) (2,900 – 80,000) cfu/ 28 260 6,400 E. coli 100mL (9 – 540) (53 – 9,000) (1,200 – 26,000) 0.02 0.01 0.32 Ammonia-nitrogen mg/L (0.01 – 0.03) (0.01 – 0.03) (0.05 – 2.00) 0.02 0.01 0.06 Nitrate-nitrogen mg/L (0.01 – 0.32) (0.01 – 0.23) (0.02 – 0.40) Total Kjeldahl 0.07 0.12 0.47 mg/L nitrogen, SP (0.05 – 0.17) (0.08 – 0.31) (0.12 – 2.50) 0.01 0.01 0.05 Ortho-phosphate mg/L (0.01 – 0.02) (0.01 – 0.01) (0.01 – 0.32) Total phosphorus, 0.02 0.02 0.07 mg/L SP (0.02 – 0.02) (0.02 – 0.06) (0.02 – 0.38) 0.02 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.02) (0.02 – 0.02) (0.02 – 0.02) 50 50 55 Aluminium µg/L (50 – 50) (50 – 980) (50 – 120) 0.1 0.1 0.1 Cadmium µg/L (0.1 – 0.1) (0.1 – 0.2) (0.1 – 0.1) 1 1 1 Chromium µg/L (1 – 1) (1 – 1) (1 – 1) 1 1 1 Copper µg/L (1 – 11) (1 – 2) (1 – 3) 1 1 1 Lead µg/L (1 – 1) (1 – 3) (1 – 1) 10 10 20 Zinc µg/L (10 – 10) (10 – 40) (10 – 30) 31 62 Flow L/s NM (6 – 840) (17 – 472) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 23 Appendix D

Summary of water quality monitoring data for Tuen Mun River in 2006 (Part 1 of 2)

Tuen Mun River Parameter Unit TN1 TN2 TN3 4.1 8.1 4.9 Dissolved oxygen mg/L (2.0 – 7.1) (6.5 – 9.6) (3.1 – 6.9) 7.6 7.5 7.6 pH (7.4 – 8.4) (7.1 – 8.5) (7.2 – 8.2) 15 16 11 Suspended solids mg/L (6 – 330) (3 – 370) (2 – 130) 5-day Biochemical 23 1 4 mg/L Oxygen Demand (6 – 45) (1 – 33) (2 – 8) Chemical Oxygen 35 9 20 mg/L Demand (21 – 60) (3 – 36) (15 – 34) 1.5 0.5 0.5 Oil & grease mg/L (0.5 – 5.1) (0.5 – 1.1) (0.5 – 0.5) cfu/ 1,000,000 35,000 140,000 Faecal coliforms 100mL (430,000 – 5,900,000) (370 – 560,000) (7,100 – 1,300,000) cfu/ 180,000 13,000 18,000 E. coli 100mL (110,000 – 250,000) (30 – 300,000) (440 – 260,000) 5.70 0.40 0.54 Ammonia-nitrogen mg/L (0.51 – 10.00) (0.16 – 5.00) (0.14 – 1.00) 0.77 0.81 0.36 Nitrate-nitrogen mg/L (0.01 – 4.70) (0.55 – 2.00) (0.11 – 0.66) Total Kjeldahl 7.05 1.00 0.98 mg/L nitrogen, SP (1.90 – 14.00) (0.27 – 5.80) (0.53 – 1.60) 0.74 0.11 0.05 Ortho-phosphate mg/L (0.27 – 1.00) (0.03 – 0.72) (0.01 – 0.12) Total phosphorus, 1.05 0.19 0.12 mg/L SP (0.79 – 1.90) (0.04 – 1.00) (0.07 – 0.22) 0.04 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.09) (0.02 – 0.07) (0.02 – 0.04) 185 145 90 Aluminium µg/L (100 – 1,600) (50 – 1,300) (50 – 540) 0.1 0.1 0.1 Cadmium µg/L (0.1 – 0.2) (0.1 – 0.2) (0.1 – 0.4) 1 1 1 Chromium µg/L (1 – 2) (1 – 1) (1 – 2) 4 3 4 Copper µg/L (3 – 17) (1 – 9) (1 – 10) 3 3 1 Lead µg/L (1 – 86) (1 – 80) (1 – 13) 30 30 15 Zinc µg/L (20 – 190) (10 – 110) (10 – 90) 119 79 Flow L/s NM (36 – 6,576) (11 – 804) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 24 Appendix D

Summary of water quality monitoring data for Tuen Mun River in 2006 (Part 2 of 2)

Tuen Mun River Parameter Unit TN4 TN5 TN6 5.5 5.0 4.7 Dissolved oxygen mg/L (3.6 – 9.5) (3.4 – 7.6) (2.3 – 7.1) 7.6 7.6 7.4 pH (7.4 – 8.0) (7.5 – 8.1) (7.3 – 7.7) 10 7 3 Suspended solids mg/L (2 – 70) (3 – 100) (1 – 17) 5-day Biochemical 4 4 3 mg/L Oxygen Demand (1 – 7) (2 – 7) (1 – 4) Chemical Oxygen 18 20 19 mg/L Demand (9 – 33) (12 – 30) (8 – 32) 0.5 0.5 0.5 Oil & grease mg/L (0.5 – 1.0) (0.5 – 0.9) (0.5 – 0.8) cfu/ 110,000 170,000 130,000 Faecal coliforms 100mL (4,600 – 830,000) (29,000 – 600,000) (16,000 – 720,000) cfu/ 20,000 28,000 15,000 E. coli 100mL (900 – 130,000) (2,900 – 120,000) (3,900 – 52,000) 0.38 0.57 0.49 Ammonia-nitrogen mg/L (0.15 – 1.00) (0.13 – 0.85) (0.12 – 0.90) 0.36 0.35 0.27 Nitrate-nitrogen mg/L (0.27 – 0.73) (0.22 – 0.83) (0.01 – 0.58) Total Kjeldahl 0.83 0.99 0.79 mg/L nitrogen, SP (0.43 – 1.50) (0.53 – 1.40) (0.43 – 1.30) 0.06 0.05 0.06 Ortho-phosphate mg/L (0.01 – 0.13) (0.02 – 0.10) (0.03 – 0.10) Total phosphorus, 0.13 0.13 0.10 mg/L SP (0.06 – 0.39) (0.08 – 0.17) (0.06 – 0.15) 0.02 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.03) (0.02 – 0.09) (0.02 – 0.02) 140 105 70 Aluminium µg/L (80 – 470) (80 – 510) (50 – 130) 0.1 0.1 0.1 Cadmium µg/L (0.1 – 0.2) (0.1 – 0.2) (0.1 – 0.1) 1 1 1 Chromium µg/L (1 – 3) (1 – 2) (1 – 3) 4 4 4 Copper µg/L (3 – 10) (2 – 12) (3 – 7) 1 1 1 Lead µg/L (1 – 14) (1 – 11) (1 – 1) 15 20 20 Zinc µg/L (10 – 100) (10 – 120) (10 – 20)

Flow L/s NM NM NM

Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 25 Appendix D

Summary of water quality monitoring data for Pai Min Kok Stream and Kau Wa Keng Stream in 2006 Pai Min Kok Stream Kau Wa Keng Stream Parameter Unit AN1 AN2 KW3 8.1 8.7 8.0 Dissolved oxygen mg/L (7.0 – 9.5) (7.7 – 10.4) (7.2 – 10.4) 8.0 8.0 7.6 pH (7.0 – 8.5) (7.0 – 8.6) (7.2 – 11.3) 4 3 6 Suspended solids mg/L (2 – 76) (1 – 4) (1 – 120) 5-day Biochemical 2 2 3 mg/L Oxygen Demand (1 – 12) (1 – 10) (1 – 9) Chemical Oxygen 12 8 17 mg/L Demand (6 – 49) (2 – 15) (6 – 34) 0.5 0.5 0.5 Oil & grease mg/L (0.5 – 0.6) (0.5 – 0.5) (0.5 – 2.5) cfu/ 150,000 58,000 48,000 Faecal coliforms 100mL (8,000 – 900,000) (6,000 – 540,000) (1 – 590,000) cfu/ 21,000 26,000 25,000 E. coli 100mL (3,200 – 68,000) (3,500 – 300,000) (1 – 320,000) 0.10 0.16 0.56 Ammonia-nitrogen mg/L (0.02 – 1.70) (0.05 – 1.60) (0.17 – 1.40) 1.45 1.30 2.05 Nitrate-nitrogen mg/L (0.58 – 5.90) (0.49 – 4.00) (0.95 – 3.50) Total Kjeldahl 0.51 0.39 1.35 mg/L nitrogen, SP (0.21 – 4.30) (0.18 – 2.20) (0.60 – 2.30) 0.13 0.11 0.16 Ortho-phosphate mg/L (0.07 – 0.90) (0.06 – 0.57) (0.01 – 0.45) Total phosphorus, 0.14 0.13 0.31 mg/L SP (0.10 – 1.40) (0.07 – 0.62) (0.08 – 0.73) 0.02 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.02) (0.02 – 0.02) (0.02 – 0.17) 120 95 120 Aluminium µg/L (80 – 240) (50 – 210) (50 – 26,000) 0.1 0.1 0.7 Cadmium µg/L (0.1 – 0.1) (0.1 – 0.1) (0.2 – 0.9) 1 1 1 Chromium µg/L (1 – 1) (1 – 1) (1 – 39) 5 3 4 Copper µg/L (2 – 8) (2 – 4) (2 – 15) 1 1 3 Lead µg/L (1 – 3) (1 – 2) (1 – 16) 30 20 70 Zinc µg/L (10 – 50) (10 – 60) (40 – 140) 8 18 Flow L/s NM (3 – 34) (12 – 136) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 26 Appendix D

Summary of water quality monitoring data for Sam Dip Tam Stream in 2006

Sam Dip Tam Stream Parameter Unit TW1 TW2 TW3 7.6 8.4 8.2 Dissolved oxygen mg/L (6.6 – 8.4) (7.9 – 9.4) (7.1 – 9.1) 7.6 7.9 7.5 pH (7.1 – 7.9) (7.3 – 8.5) (7.2 – 8.1) 3 2 2 Suspended solids mg/L (1 – 6) (1 – 9) (1 – 21) 5-day Biochemical 1 2 1 mg/L Oxygen Demand (1 – 16) (1 – 6) (1 – 3) Chemical Oxygen 4 6 6 mg/L Demand (2 – 11) (2 – 10) (2 – 11) 0.5 0.5 0.5 Oil & grease mg/L (0.5 – 0.5) (0.5 – 0.5) (0.5 – 0.5) cfu/ 73,000 110,000 30,000 Faecal coliforms 100mL (12,000 – 700,000) (25,000 – 2,300,000) (4,300 – 540,000) cfu/ 10,000 31,000 9,000 E. coli 100mL (2,300 – 340,000) (5,500 – 210,000) (1,100 – 83,000) 0.05 0.29 0.11 Ammonia-nitrogen mg/L (0.01 – 0.22) (0.03 – 1.30) (0.03 – 0.62) 0.78 1.20 1.55 Nitrate-nitrogen mg/L (0.21 – 1.40) (0.41 – 1.50) (0.59 – 2.00) Total Kjeldahl 0.24 0.69 0.31 mg/L nitrogen, SP (0.06 – 0.79) (0.13 – 1.70) (0.08 – 0.94) 0.03 0.16 0.13 Ortho-phosphate mg/L (0.01 – 0.06) (0.02 – 0.29) (0.03 – 0.27) Total phosphorus, 0.06 0.19 0.14 mg/L SP (0.02 – 0.09) (0.04 – 0.30) (0.04 – 0.38) 0.02 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.02) (0.02 – 0.02) (0.02 – 0.02) 50 50 50 Aluminium µg/L (50 – 110) (50 – 150) (50 – 100) 0.1 0.1 0.1 Cadmium µg/L (0.1 – 0.3) (0.1 – 0.1) (0.1 – 0.1) 1 1 1 Chromium µg/L (1 – 1) (1 – 1) (1 – 1) 2 2 2 Copper µg/L (1 – 8) (1 – 3) (1 – 3) 1 1 1 Lead µg/L (1 – 6) (1 – 3) (1 – 3) 20 20 10 Zinc µg/L (10 – 40) (10 – 30) (10 – 30) 78 Flow L/s NM NM (9 – 224) Notes: 1. Data presented are in annual medians of monthly samples; except those for faecal coliforms and E. coli which are in annual geometric means. 2. Figures in brackets are annual ranges. 3. NM indicates no measurement taken. 4. cfu - colony forming unit. 5. SP - soluble and particulate fractions i.e. total value. 6. Values at or below laboratory reporting limits are presented as laboratory reporting limits (see Appendix B). 7. Equal values for annual medians (or geometric means) and ranges indicate that all data are the same as or below laboratory reporting limits.

River Water Quality in Hong Kong in 2006 D - 27 Appendix D

Summary of water quality monitoring data for Kai Tak Nullah in 2006 (Part 1 of 2)

Kai Tak Nullah Parameter Unit KN1 KN2 KN3 5.9 6.8 7.6 Dissolved oxygen mg/L (4.1 – 7.2) (6.2 – 7.3) (7.2 – 8.0) 7.1 7.2 7.4 pH (7.0 – 7.5) (7.0 – 7.3) (7.1 – 7.5) 9 10 10 Suspended solids mg/L (1 – 20) (6 – 14) (3 – 15) 5-day Biochemical 7 3 2 mg/L Oxygen Demand (4 – 25) (2 – 3) (2 – 4) Chemical Oxygen 40 23 28 mg/L Demand (13 – 58) (22 – 32) (13 – 29) 0.5 0.5 0.5 Oil & grease mg/L (0.5 – 1.1) (0.5 – 0.5) (0.5 – 0.5) cfu/ 1,100,000 110,000 110,000 Faecal coliforms 100mL (40,000 – 4,900,000) (47,000 – 260,000) (59,000 – 190,000) cfu/ 580,000 53,000 39,000 E. coli 100mL (26,000 – 2,500,000) (26,000 – 100,000) (18,000 – 55,000) 1.03 0.42 0.28 Ammonia-nitrogen mg/L (0.49 – 6.70) (0.13 – 0.60) (0.11 – 0.51) 4.70 5.45 5.90 Nitrate-nitrogen mg/L (0.73 – 6.80) (4.70 – 7.00) (4.90 – 6.80) Total Kjeldahl 2.20 1.45 1.30 mg/L nitrogen, SP (1.70 – 8.70) (1.00 – 1.60) (0.94 – 1.70) 1.75 1.90 1.95 Ortho-phosphate mg/L (0.88 – 2.00) (1.60– 2.00) (1.70 – 2.00) Total phosphorus, 2.00 2.05 2.05 mg/L SP (0.97 – 2.10) (1.70 – 2.20) (1.70 – 2.10) 0.24 0.02 0.02 Sulphide, SP mg/L (0.02 – 4.30) (0.02 – 0.02) (0.02 – 0.02) 50 50 50 Aluminium µg/L (50 – 80) (50 – 50) (50 – 50) 0.1 0.1 0.1 Cadmium µg/L (0.1 – 0.3) (0.1 – 0.1) (0.1 – 0.1) 1 1 1 Chromium µg/L (1 – 14) (1 – 2) (1 – 1) 9 7 8 Copper µg/L (3 – 13) (5 – 9) (6 – 9) 1 1 1 Lead µg/L (1 – 1) (1 – 1) (1 – 1) 30 35 30 Zinc µg/L (20 – 950) (30 – 60) (20 – 60)

Flow L/s NM NM NM

River Water Quality in Hong Kong in 2006 D - 28 Appendix D

Summary of water quality monitoring data for Kai Tak Nullah in 2006 (Part 2 of 2)

Kai Tak Nullah Parameter Unit KN4 KN5 KN7 8.0 7.9 7.4 Dissolved oxygen mg/L (7.1 – 8.8) (7.1 – 8.8) (6.8 – 8.3) 7.4 7.3 7.3 pH (7.1 – 7.5) (7.1 – 7.5) (7.0 – 7.4) 7 8 6 Suspended solids mg/L (3 – 27) (2 – 21) (2 – 20) 5-day Biochemical 3 3 3 mg/L Oxygen Demand (2 – 7) (1 – 8) (2 – 7) Chemical Oxygen 34 34 26 mg/L Demand (18 – 57) (13 – 58) (16 – 49) 0.5 0.5 0.5 Oil & grease mg/L (0.5 – 0.6) (0.5 – 0.5) (0.5 – 0.5) cfu/ 120,000 120,000 120,000 Faecal coliforms 100mL (48,000 – 300,000) (53,000 – 350,000) (57,000 – 350,000) cfu/ 51,000 47,000 48,000 E. coli 100mL (27,000 – 130,000) (29,000 – 180,000) (31,000 – 140,000) 0.25 0.29 0.24 Ammonia-nitrogen mg/L (0.10 – 0.85) (0.09 – 0.80) (0.09 – 0.67) 5.40 5.40 5.35 Nitrate-nitrogen mg/L (4.50 – 7.70) (4.40 – 6.90) (4.70 – 7.20) Total Kjeldahl 1.20 1.20 1.30 mg/L nitrogen, SP (0.90 – 1.90) (0.80 – 1.90) (0.88 – 1.80) 1.80 1.75 1.75 Ortho-phosphate mg/L (1.50 – 1.90) (1.50 – 2.00) (1.50 – 1.90) Total phosphorus, 1.90 1.90 1.90 mg/L SP (1.60 – 2.30) (1.60 – 2.40) (1.60 – 2.20) 0.02 0.02 0.02 Sulphide, SP mg/L (0.02 – 0.02) (0.02 – 0.02) (0.02 – 0.05) 50 50 50 Aluminium µg/L (50 – 50) (50 – 50) (50 – 70) 0.1 0.1 0.1 Cadmium µg/L (0.1 – 0.1) (0.1 – 0.1) (0.1 – 0.1) 1 1 1 Chromium µg/L (1 – 4) (1 – 2) (1 – 2) 7 7 9 Copper µg/L (5 – 620) (1 – 21) (4 – 21) 1 1 1 Lead µg/L (1 – 2) (1 – 1) (1 – 4) 30 25 30 Zinc µg/L (20 – 910) (10 – 630) (20 – 770)

Flow L/s NM NM NM

River Water Quality in Hong Kong in 2006 D - 29 Appendix E

Compliance with the river Water Quality Objectives in 2006

5-Day Chemical Biochemical Dissolved Suspended Overall Watercourse pH Oxygen Oxygen Oxygen Solids Compliance Demand Demand Eastern New Territories Shing Mun River 92% 84% 93% 99% 100% 94% Lam Tsuen River 99% 83% 94% 98% 100% 95% Tai Po River 92% 67% 100% 100% 100% 92% Tai Po Kau Stream 100% 100% 100% 100% 100% 100% Shan Liu Stream 100% 100% 100% 100% 100% 100% Tung Tze Stream 100% 92% 92% 100% 100% 97% Ho Chung River 100% 100% 100% 100% 100% 100% Sha Kok Mei Stream 100% 100% 100% 100% 100% 100% Tai Chung Hau Stream 100% 100% 100% 100% 100% 100% Tseng Lan Shue Stream 100% 64% 89% 97% 100% 90% Northwestern New Territories River Indus 100% 53% 64% 83% 67% 73% River Beas 100% 42% 53% 97% 100% 78% River Ganges 100% 28% 36% 78% 67% 62% Yuen Long Creek 100% 2% 0% 40% 25% 33% Kam Tin River 100% 0% 8% 38% 50% 39% Tin Shui Wai Nullah 88% 63% 92% 88% 50% 76% Fairview Park Nullah 100% 8% 25% 92% 0% 45% Ha Pak Nai Stream 100% 100% 100% 100% 100% 100% Tai Shui Hang Stream 100% 100% 100% 100% 100% 100% Pak Nai Stream 100% 100% 100% 100% 100% 100% Sheung Pak Nai Stream 100% 100% 100% 100% 100% 100% Ngau Hom Sha Stream 100% 58% 83% 100% 100% 88% Tsang Kok Stream 100% 100% 100% 100% 100% 100% Lantau Island Mui Wo River 100% 100% 98% 100% 100% 99% Tung Chung River 97% 97% 100% 100% 100% 99% Southwestern New Territories & Kowloon Tuen Mun River 99% 69% 76% 82% 100% 85% Pai Min Kok Stream 100% 75% 96% 100% 100% 94% Kau Wa Keng Stream 92% 67% 92% 100% 100% 90% Sam Dip Tam Stream 100% 94% 100% 100% 100% 99% Kai Tak Nullah Not applicable Average Compliance 98% 73% 81% 91% 89% 86% (All monitoring stations)

River Water Quality in Hong Kong in 2006 E - 1 Appdendix F

Water Quality Index gradings and E. coli levels in Shing Mun River

River Water Quality in Hong Kong 2006 F- 1 Appdendix F

Water Quality Index gradings and E. coli levels in Lam Tsuen River and Tai Po River

River Water Quality in Hong Kong 2006 F- 2 Appdendix F

Water Quality Index gradings and E. coli levels in Tai Po Kau Stream, Shan Liu Stream and Tung Tze Stream

River Water Quality in Hong Kong 2006 F- 3 Appdendix F

Water Quality Index gradings and E. coli levels in Ho Chung River, Tai Chung Hau Stream and Sha Kok Mei Stream

River Water Quality in Hong Kong 2006 F- 4 Appdendix F

Water Quality Index gradings and E. coli levels in Tseng Lan Shue Stream

River Water Quality in Hong Kong 2006 F- 5 Appdendix F

Water Quality Index gradings and E. coli levels in River Indus, River Beas and River Ganges

River Water Quality in Hong Kong 2006 F- 6 Appdendix F

Water Quality Index gradings and E. coli levels in Yuen Long Creek, Kam Tin River, Tin Shui Wai Nullah and Fairview Park Nullah

River Water Quality in Hong Kong 2006 F- 7 Appdendix F

Water Quality Index gradings and E. coli levels in Ha Pak Nai Stream, Tai Shui Hang Stream, Pak Nai Stream, Sheung Pak Nai Stream, Ngau Hom Sha Stream and Tsang Kok Stream

River Water Quality in Hong Kong 2006 F- 8 Appdendix F

Water Quality Index gradings and E. coli levels in Mui Wo River

River Water Quality in Hong Kong 2006 F- 9 Appdendix F

Water Quality Index gradings and E. coli levels in Tung Chung River

River Water Quality in Hong Kong 2006 F- 10 Appdendix F

Water Quality Index gradings and E. coli levels in Tuen Mun River

River Water Quality in Hong Kong 2006 F- 11 Appdendix F

Water Quality Index gradings and E. coli levels in Pai Min Kok Stream, Sam Dip Tam Stream and Kau Wa Keng Stream

River Water Quality in Hong Kong 2006 F- 12 Appdendix F

Water Quality Index gradings and E. coli levels in Kai Tak Nullah

River Water Quality in Hong Kong 2006 F- 13 Appendix G

Water quality trends for Shing Mun River (Main Channel, Siu Lek Yuen Nullah and Fo Tan Nullah) as analysed by the Seasonal Kendall Test Shing Mun River Watercourse Main Siu Lek Yuen Fo Tan Nullah Channel Nullah Monitoring station TR19I TR23L TR23A TR17 TR17L Monitoring period* 86-06 86-06 86-06 86-06 86-06 Parameter Unit Results of the Seasonal Kendall Test Dissolved oxygen mg/L − pH − − Suspended solids mg/L

BOD5 mg/L COD mg/L Oil & grease mg/L − − − E. coli cfu/100mL − Faecal coliforms cfu/100mL − − − − Ammonia-nitrogen mg/L − Nitrate-nitrogen mg/L − − Total Kjeldahl nitrogen (SP) mg/L Ortho-phosphate mg/L Total phosphorus (SP) mg/L Sulphide (SP) mg/L − − − − − Aluminium µg/L − − − Cadmium µg/L − − − − − Chromium µg/L − − − − Copper µg/L − − Lead µg/L − − − Zinc µg/L − − − Flow L/s × − × − ×

Notes: 1. (SP) soluble and particulate fractions (i.e. total) of the water quality parameter. 2. − indicates no significant trend was detected at p < 0.05. 3. represents an increasing trend significant at p < 0.05. 4. represents a decreasing trend significant at p < 0.05. 5. × indicates no measurement was taken. 6. * indicates the monitoring period for most of the parameters, a few commenced in different years during the period.

River Water Quality in Hong Kong in 2006 G - 1 Appendix G

Water quality trends for Shing Mun River (Kwun Yam Shan Stream, Tai Wai Nullah and Tin Sum Nullah) as analysed by the Seasonal Kendall Test Shing Mun River Kwun Watercourse Yam Tin Sum Tai Wai Nullah Shan Nullah Stream Monitoring station KY1 TR19A TR19C TR19 TR20B Monitoring period* 88-06 86-06 86-06 86-06 86-06 Parameter Unit Results of the Seasonal Kendall Test Dissolved oxygen mg/L − − − pH − − − Suspended solids mg/L − −

BOD5 mg/L COD mg/L Oil & grease mg/L − − − − E. coli cfu/100mL − − Faecal coliforms cfu/100mL − Ammonia-nitrogen mg/L Nitrate-nitrogen mg/L − − Total Kjeldahl nitrogen (SP) mg/L Ortho-phosphate mg/L − Total phosphorus (SP) mg/L Sulphide (SP) mg/L − − − − − Aluminium µg/L − − − − Cadmium µg/L − − Chromium µg/L − − − − Copper µg/L − − − Lead µg/L − − Zinc µg/L − − − − Flow L/s − − − −

River Water Quality in Hong Kong in 2006 G - 2 Appendix G

Water quality trends for Lam Tsuen River and Tai Po River, as analysed by the Seasonal Kendall Test Tai Watercourse Lam Tsuen River Po River Monitoring station TR12H TR12D TR12G TR12F TR12C TR12B TR12E TR12 TR12I TR13 Monitoring period* 88-06 86-06 86-06 86-06 86-06 86-06 86-06 86-06 89-06 86-06 Parameter Unit Results of the Seasonal Kendall Test Dissolved oxygen mg/L − − pH − − − − − − Suspended solids mg/L −

BOD5 mg/L − COD mg/L − Oil & grease mg/L − − − − − − − − − − E. coli cfu/100mL − − − − − − − Faecal coliforms cfu/100mL − − − − − − − − − Ammonia-nitrogen mg/L − − − Nitrate-nitrogen mg/L − − − Total Kjeldahl mg/L nitrogen (SP) Ortho-phosphate mg/L − − Total phosphorus mg/L (SP) Sulphide (SP) mg/L − − − − − − − − − − Aluminium µg/L − − − − − − − Cadmium µg/L − − − − − − − − − − Chromium µg/L − − − − − − − − − − Copper µg/L − − − − − − − − Lead µg/L − − − − − − − Zinc µg/L − − − − − − − − − − Flow L/s − − − − − − × −

River Water Quality in Hong Kong in 2006 G - 3 Appendix G

Water quality trends for Tai Po Kau Stream, Shan Liu Stream and Tung Tze Stream, as analysed by the Seasonal Kendall Test Tai Po Kau Shan Liu Tung Tze Watercourse Stream Stream Stream

Monitoring station TR14 TR4 TR6 Monitoring period* 86-06 86-06 86-06 Parameter Unit Results of the Seasonal Kendall Test Dissolved oxygen mg/L − − pH − Suspended solids mg/L −

BOD5 mg/L − COD mg/L − Oil & grease mg/L − − − E. coli cfu/100mL − − Faecal coliforms cfu/100mL − − − Ammonia-nitrogen mg/L − Nitrate-nitrogen mg/L − Total Kjeldahl nitrogen (SP) mg/L − Ortho-phosphate mg/L − − Total phosphorus (SP) mg/L − Sulphide (SP) mg/L − − − Aluminium µg/L − − − Cadmium µg/L − − − Chromium µg/L − − − Copper µg/L − − Lead µg/L − − − Zinc µg/L − − − Flow L/s − ×

River Water Quality in Hong Kong in 2006 G - 4 Appendix G

Water quality trends for Ho Chung River, Sha Kok Mei Stream and Tai Chung Hau Stream, as analysed by the Seasonal Kendall Test Tai Chung Hau Watercourse Ho Chung River Sha Kok Mei Stream Stream Monitoring station PR1 PR2 PR5 PR6 PR7 PR8 Monitoring period* 86-06 86-06 89-06 89-06 89-06 89-06 Parameter Unit Results of the Seasonal Kendall Test Dissolved oxygen mg/L pH − − Suspended solids mg/L −

BOD5 mg/L − COD mg/L − Oil & grease mg/L − − − − − − E. coli cfu/100mL − − − − − Faecal coliforms cfu/100mL − − − − Ammonia-nitrogen mg/L − Nitrate-nitrogen mg/L − − − Total Kjeldahl mg/L nitrogen (SP) − Ortho-phosphate mg/L Total phosphorus mg/L (SP) Sulphide (SP) mg/L − − − − − − Aluminium µg/L − − − Cadmium µg/L − − − − − − Chromium µg/L − − − − − Copper µg/L − − − − Lead µg/L − − − − − Zinc µg/L − − − − − Flow L/s × − × ×

River Water Quality in Hong Kong in 2006 G - 5 Appendix G

Water quality trends for Tseng Lan Shue Stream, as analysed by the Seasonal Kendall Test

Watercourse Tseng Lan Shue Stream

Monitoring station JR3 JR6 JR11 Monitoring period* 86-06 86-06 86-06 Parameter Unit Results of the Seasonal Kendall Test Dissolved oxygen mg/L pH Suspended solids mg/L

BOD5 mg/L COD mg/L Oil & grease mg/L − − − E. coli cfu/100mL − Faecal coliforms cfu/100mL − − Ammonia-nitrogen mg/L Nitrate-nitrogen mg/L − Total Kjeldahl nitrogen (SP) mg/L Ortho-phosphate mg/L Total phosphorus (SP) mg/L Sulphide (SP) mg/L − − − Aluminium µg/L − − − Cadmium µg/L − − − Chromium µg/L − − − Copper µg/L − Lead µg/L − − Zinc µg/L − − Flow L/s × × −

River Water Quality in Hong Kong in 2006 G - 6 Appendix G

Water quality trends for River Indus, River Beas and River Ganges, as analysed by the Seasonal Kendall Test

Watercourse River Indus River Beas River Ganges Monitoring station IN1 IN2 IN3 RB1 RB2 RB3 GR1 GR2 GR3 Monitoring period* 87-06 87-06 87-06 86-06 86-06 86-06 87-06 87-06 90-06 Parameter Unit Results of the Seasonal Kendall Test Dissolved oxygen mg/L − pH − Suspended solids mg/L − −

BOD5 mg/L − COD mg/L − Oil & grease mg/L − − − − − − − E. coli cfu/100mL − Faecal coliforms cfu/100mL − Ammonia-nitrogen mg/L − − Nitrate-nitrogen mg/L − − Total Kjeldahl nitrogen (SP) mg/L Ortho-phosphate mg/L Total phosphorus (SP) mg/L Sulphide (SP) mg/L − − Aluminium µg/L − − − − Cadmium µg/L − − − − − − − − − Chromium µg/L − − − − − − − − Copper µg/L − − Lead µg/L − − Zinc µg/L − − Flow L/s × × − − − × −

River Water Quality in Hong Kong in 2006 G - 7 Appendix G

Water quality trends for Yuen Long Creek, Kam Tin River, Tin Shui Wai Nullah and Fairview Park Nullah as analysed by the Seasonal Kendall Test Kam Tin Tin Shui Wai Fairview Watercourse Yuen Long Creek River Nullah Park Nullah Monitoring station YL1 YL2 YL3 YL4 KT1 KT2 TSR1 TSR2 FVR1 Monitoring period* 86-06 86-06 86-06 86-06 86-06 86-06 93-06 93-06 93-06 Parameter Unit Results of the Seasonal Kendall Test Dissolved oxygen mg/L pH − Suspended solids mg/L − − − −

BOD5 mg/L COD mg/L − − − Oil & grease mg/L − − − − − E. coli cfu/100mL − − − Faecal coliforms cfu/100mL − − − − Ammonia-nitrogen mg/L Nitrate-nitrogen mg/L − − − − − Total Kjeldahl mg/L nitrogen (SP) Ortho-phosphate mg/L Total phosphorus (SP) mg/L Sulphide (SP) mg/L − − Aluminium µg/L − − − − − − − − Cadmium µg/L − − − − − − − − Chromium µg/L − − − − − − Copper µg/L − − − − − Lead µg/L − − − − − − Zinc µg/L − − − − − Flow L/s − − − − − × − ×

River Water Quality in Hong Kong in 2006 G - 8 Appendix G

Water quality trends for Ha Pak Nai Stream, Pak Nai Stream, Sheung Pak Nai Stream, Ngau Hom Sha Stream, Tai Shui Hang Stream and Tsang Kok Stream as analysed by the Seasonal Kendall Test Ha Pak Sheung Ngau Hom Tai Shui Tsang Pak Nai Watercourse Nai Pak Nai Sha Hang Kok Stream Stream Stream Stream Stream Stream Monitoring station DB1 DB3 DB5 DB6 DB2 DB8 Monitoring period* 89-06 89-06 89-06 89-06 89-06 90-06 Parameter Unit Results of the Seasonal Kendall Test Dissolved oxygen mg/L pH − − Suspended solids mg/L −

BOD5 mg/L COD mg/L − Oil & grease mg/L − − − − − − E. coli cfu/100mL − − − − − Faecal coliforms cfu/100mL − − − − − Ammonia-nitrogen mg/L − − − Nitrate-nitrogen mg/L − Total Kjeldahl nitrogen mg/L (SP) Ortho-phosphate mg/L Total phosphorus (SP) mg/L Sulphide (SP) mg/L − − − − − Aluminium µg/L − − − Cadmium µg/L − − − − − Chromium µg/L − − − − − − Copper µg/L − − − − − − Lead µg/L − − Zinc µg/L − − − − − Flow L/s − − − − − ×

River Water Quality in Hong Kong in 2006 G - 9 Appendix G

Water quality trends for Mui Wo River as analysed by the Seasonal Kendall Test

Watercourse Mui Wo River Monitoring station MW1 MW2 MW3 MW4 MW5 Monitoring period* 86-06 86-06 86-06 88-06 88-06 Parameter Unit Results of the Seasonal Kendal Test Dissolved oxygen mg/L − pH − − − Suspended solids mg/L − −

BOD5 mg/L − COD mg/L − Oil & grease mg/L − − − − − E. coli cfu/100mL − − − Faecal coliforms cfu/100mL − − Ammonia-nitrogen mg/L − Nitrate-nitrogen mg/L − − − Total Kjeldahl nitrogen mg/L (SP) − − Ortho-phosphate mg/L − − − Total phosphorus (SP) mg/L − Sulphide (SP) mg/L − − − − − Aluminium µg/L − − − − − Cadmium µg/L − − − − − Chromium µg/L − − − − − Copper µg/L − − − − Lead µg/L − − − − Zinc µg/L − − − − − Flow L/s − × − −

River Water Quality in Hong Kong in 2006 G - 10 Appendix G

Water quality trends for Tung Chung River as analysed by the Seasonal Kendall Test

Watercourse Tung Chung River Monitoring station TC1 TC2 TC3 Monitoring period* 93-06 93-06 93-06 Parameter Unit Results of the Seasonal KendallTest Dissolved oxygen mg/L − − pH − Suspended solids mg/L −

BOD5 mg/L − − COD mg/L − Oil & grease mg/L − − − E. coli cfu/100mL − − Faecal coliforms cfu/100mL Ammonia-nitrogen mg/L Nitrate-nitrogen mg/L − − − Total Kjeldahl nitrogen mg/L (SP) Ortho-phosphate mg/L − − Total phosphorus (SP) mg/L − − − Sulphide (SP) mg/L − − − Aluminium µg/L − − − Cadmium µg/L − − − Chromium µg/L − − − Copper µg/L − − − Lead µg/L − − − Zinc µg/L − − − Flow L/s − − ×

River Water Quality in Hong Kong in 2006 G - 11 Appendix G

Water quality trends for Tuen Mun River as analysed by the Seasonal Kendall Test

Watercourse Tuen Mun River Monitoring station TN1 TN2 TN3 TN4 TN5 TN6 Monitoring period* 86-06 86-06 86-06 86-06 86-06 86-06 Parameter Unit Results of the Seasonal Kendall Test Dissolved oxygen mg/L pH − − − − − Suspended solids mg/L − − −

BOD5 mg/L COD mg/L Oil & grease mg/L − − − − E. coli cfu/100mL Faecal coliforms cfu/100mL Ammonia-nitrogen mg/L Nitrate-nitrogen mg/L Total Kjeldahl nitrogen (SP) mg/L Ortho-phosphate mg/L Total phosphorus (SP) mg/L Sulphide (SP) mg/L − − − − Aluminium µg/L − − − − Cadmium µg/L − − − − − Chromium µg/L Copper µg/L Lead µg/L − Zinc µg/L − − − − − Flow L/s − × × × ×

River Water Quality in Hong Kong in 2006 G - 12 Appendix G

Water quality trends for Pai Min Kok Stream, Sam Dip Tam Stream and Kau Wa Keng Stream as analysed by the Seasonal Kendall Test Kau Wa Pai Min Kok Watercourse Sam Dip Tam Stream Keng Stream Stream Monitoring station AN1 AN2 TW1 TW2 TW3 KW3 Monitoring period* 88-06 88-06 86-06 86-06 86-06 88-06 Parameter Unit Results of the Seasonal Kendall Test Dissolved oxygen mg/L pH − Suspended solids mg/L −

BOD5 mg/L − COD mg/L Oil & grease mg/L − − − − − − E. coli cfu/100mL − − − − − − Faecal coliforms cfu/100mL − − − − Ammonia-nitrogen mg/L − Nitrate-nitrogen mg/L − − Total Kjeldahl nitrogen (SP) mg/L Ortho-phosphate mg/L Total phosphorus (SP) mg/L Sulphide (SP) mg/L − − − − − − Aluminium µg/L − − − − − Cadmium µg/L − − − − − − Chromium µg/L − − − − − − Copper µg/L − − − − − Lead µg/L − Zinc µg/L − − − − − Flow L/s × − × − × −

River Water Quality in Hong Kong in 2006 G - 13 Appendix G

Water quality trends for Kai Tak Nullah as analysed by the Seasonal Kendall Test

Watercourse Kai Tak Nullah Monitoring station KN1 KN2 KN3 KN4 KN5 KN7 Monitoring period* 86-06 86-06 86-06 86-06 86-06 86-06 Parameter Unit Results of the Seasonal Kendall Test Dissolved oxygen mg/L − pH − − Suspended solids mg/L

BOD5 mg/L COD mg/L Oil & grease mg/L − − E. coli cfu/100mL − − − Faecal coliforms cfu/100mL − − − Ammonia-nitrogen mg/L Nitrate-nitrogen mg/L Total Kjeldahl nitrogen (SP) mg/L Ortho-phosphate mg/L − − Total phosphorus (SP) mg/L − − − − − Sulphide (SP) mg/L − − − Aluminium µg/L Cadmium µg/L − Chromium µg/L Copper µg/L Lead µg/L Zinc µg/L − − − − Flow L/s × × × × × ×

River Water Quality in Hong Kong in 2006 G - 14