Water Quality of Victoria Harbour and Its Typhoon Shelters

Drainage Services Department

July 2018 Rundown

The HATS and its Improvements Enhancing System Robustness & Planned Maintenance of HATS Stage 1

Further Enhancement of Coastal Water Quality 2

The HATS and Its Improvements

3 Pre-HATS (before 2001)

Kwai Chung • Preliminary Treatment Works (PTW)

Tsing Yi • Screened sewage discharged at PTWs

North West Kowloon

To Kwa Wan Kwun Tong Kowloon Tseung Kwan O

North Point Central Wan Chai Sandy Bay East Shau Kei Wan

Cyberport Hong Kong Island Chai Wan Wah Fu

Aberdeen

Ap Lei Chau

4 HATS Stage 1 (2001 - 2015)

Kwai Chung • Preliminary Treatment Works (PTW)

Tsing Yi • Screened sewage discharged at PTWs

Stonecutters Deep Sewage Tunnel Island STW

NWKPTW To Kwa Wan Kwun Tong Submarine outfall of Kowloon Tseung Kwan O SCISTW

North Point Central Wan Chai Sandy Bay East Shau Kei Wan

Cyberport Hong Kong Island Chai Wan Wah Fu

Aberdeen

Ap Lei Chau

5 HATS Stage 1 + Stage 2A

6 Water Quality in Victoria Harbour

HATS 1 Commissioned

Disinfection Commissioned

HATS 2A Commissioned

7 Water Quality in Victoria Harbour

8 8 Water Quality in Victoria Harbour

2011 – Cross harbour Race revived, after suspension for 33 years

2017 – Race route resumed at central Harbour: Tsim Sha Tsui to Wanchai 9

Enhancing System Robustness & Planned Maintenance of HATS Stage 1

10 HATS Stage 1 + Stage 2A

11 Enhancing System Robustness Interconnection Tunnel between Main Pumping Stations MPS1 and MPS2 commissioned in Jan 2017)

HATS 1 sewage from eastern HATS 1 sewage tunnel (A) A from western tunnel (B)

MPS1

Note: (A) Sewage from Chai Wan PTW, Shau Kei Wan PTW, Tseung Kwan O PTW, Kwun Tong PTW and To Kwa Wan PTW (B) Sewage from Kwai Chung PTW and Tsing Yi PTW 12 Enhancing System Robustness Interconnection Tunnel between Main Pumping Stations MPS1 and MPS2 commissioned in Jan 2017)

HATS 2A sewage

HATS 1 sewage MPS2 from eastern HATS 1 sewage tunnel (A) A from western tunnel (B)

MPS1

Note: (A) Sewage from Chai Wan PTW, Shau Kei Wan PTW, Tseung Kwan O PTW, Kwun Tong PTW and To Kwa Wan PTW (B) Sewage from Kwai Chung PTW and Tsing Yi PTW 13 Enhancing System Robustness Interconnection Tunnel between Main Pumping Stations MPS1 and MPS2 (commissioned in Jan 2017)

HATS 2A sewage

HATS 1 sewage MPS2 from eastern HATS 1 sewage tunnel (A) A from western tunnel (B)

MPS1

Note: (A) Sewage from Chai Wan PTW, Shau Kei Wan PTW, Tseung Kwan O PTW, Kwun Tong PTW and To Kwa Wan PTW (B) Sewage from Kwai Chung PTW and Tsing Yi PTW 14 Enhancing System Robustness

連接隧道 (2017年1月啟用)

Interconnection Tunnel 淨化海港計劃第二期甲 between MPS1 and MPS2 污水隧道

2號 MPS2 淨化海港計劃第一期主泵房東面污水隧道(A) 淨化海港計劃第一期 A 西面污水隧道 (B) MPS1

需更換的 1號及2號水閘 1號主泵房

A Stonecutters Island Sewage Treatment Works

註釋: (A) 從柴灣、筲箕灣、將軍澳、觀塘及土瓜灣基本污水處理廠之污水 15 (B) 從葵涌及青衣基本污水處理廠之污水 Enhancing System Robustness Interconnection Tunnel between Main Pumping Stations MPS1 and MPS2 (commissioned in Jan 2017)

HATS 2A sewage

HATS 1 sewage MPS2 from eastern HATS 1 sewage tunnel (A) A from western tunnel (B)

MPS1

Note: (A) Sewage from Chai Wan PTW, Shau Kei Wan PTW, Tseung Kwan O PTW, Kwun Tong PTW and To Kwa Wan PTW (B) Sewage from Kwai Chung PTW and Tsing Yi PTW 16 Enhancing System Robustness Interconnection Tunnel between Main Pumping Stations MPS1 and MPS2 (commissioned in Jan 2017)

HATS 2A sewage

HATS 1 sewage MPS2 from eastern HATS 1 sewage tunnel (A) A from western tunnel (B)

Penstocks No. 1 & 2 MPS1 to be replaced A

Note: (A) Sewage from Chai Wan PTW, Shau Kei Wan PTW, Tseung Kwan O PTW, Kwun Tong PTW and To Kwa Wan PTW (B) Sewage from Kwai Chung PTW and Tsing Yi PTW 17 18 Main Pumping Station No. 1 (MPS1) 18 Inlet Chamber of MPS1  Deep location Access opening,  34m below ground level 47m above  Safety Precautions  Confined Space  Hazardous sewerage environment

Ground level

Inlet Chamber

34 m Penstock 1 Penstocks 1, 2

Penstock 2

Inlet Chamber of MPS1 Sewage from HATS 1

19 Timeline of Works Sequence and Sewage Bypass

20 Temporary Bypass at 7 PTWs of HATS 1

Kwai Chung • Discharge Location of PTW

• Normal treatment and disposal for Tsing Yi flows from NWKPTW and HATS 2A

• Preliminary Treatment Works (PTW) Stonecutters Deep Sewage Tunnel Island STW

NWKPTW To Kwa Wan Kwun Tong Submarine outfall of Kowloon Tseung Kwan O SCISTW

North Point Central Wan Chai Sandy Bay East Shau Kei Wan

Deep Sewage Tunnel Cyberport Hong Kong Island Chai Wan Wah Fu

Aberdeen

Ap Lei Chau

21 21 HATS 1 Penstocks Replacement  17 years of unceasing operation since 2001

 Temporary sewage bypass (in non-bathing season, 5 episodes each not exceeding 2 weeks)

 Water Quality Modelling – potential impact low and transient

 Consultation with the ACE and the LegCo EA Panel

 Inter-departmental working group

 First bypass completed (20 Feb – 4 Mar 2018)

22 Conditions during the 1st bypass

Tsuen Wan Promenade

23 Conditions during the 1st bypass

Hung Hom Promenade

24 Conditions during the 1st bypass

Siu Sai Wan Promenade

25 Conditions during the 1st bypass

Aldrich Bay Promenade

26 Water Quality Monitoring

27 Water Quality Monitoring Results (1st bypass) Beaches

Baseline Bypass Post-bypass

28 Water Quality Monitoring Results (1st bypass)

Fish Culture Zones

29 Water Quality Monitoring Results (1st bypass) Promenades

30 Marine Stations

31 31 Marine Stations

32 32 HATS 1 Penstocks Replacement  17 years of unceasing operation since 2001

 Temporary sewage bypass (in non-bathing season, 5 episodes each not exceeding 2 weeks)

 Water Quality Modelling – potential impact low and transient

 Consultation with the ACE and the LegCo EA Panel

 Inter-departmental working group

 First bypass completed (20 Feb – 4 Mar 2018)  Water quality in line with the model prediction  Water quality monitoring results uploaded to DSD website

 Next bypass episodes (early Nov 2018 and early Mar 2019)  Manufacturing of new penstocks underway.

 Further enhancing the robustness and reliability of HATS system 33

Further Enhancement of Coastal Water Quality

34 Further Enhancement of Coastal Water Quality

Wan Chai East  Dry Weather Flow Hung Hom

Tsuen Wan Bay Interceptors Cheung Sha Wan Tai Kok Tsui New Yau Ma Tei Typhoon Shelter  New Central Harbourfront Territorial wide sewer Causeway Bay Typhoon Shelter Shau Kei Wan Typhoon Shelter rehabilitation To Kwa Wan / Ma Tau Kok

 Odour reduction measures in stormwater networks

35 Thank You