![1989 - Formulation of the Strategic Sewage Disposal Scheme 1989 - Formulation of the Strategic Sewage Disposal Scheme](https://www.dsd.gov.hk/HATS_monograph/assets/images/2021/07/dsd_map_book.jpg)
1989 - Formulation of the Strategic Sewage Disposal Scheme
![1994 -Commencement of works on Harbour Area Treatment Scheme (HATS) Stage 1 1994 -Commencement of works on Harbour Area Treatment Scheme (HATS) Stage 1](https://www.dsd.gov.hk/HATS_monograph/assets/images/2020/01/1994.png)
1994 - Commencement of works on Harbour Area Treatment Scheme (HATS) Stage 1
![1997 - Commissioning of chemically enhanced primary treatment works at Stonecutters Island, as part of HATS 1997 - Commissioning of chemically enhanced primary treatment works at Stonecutters Island, as part of HATS](https://www.dsd.gov.hk/HATS_monograph/assets/images/2020/01/1997.png)
1997 - Commissioning of chemically enhanced primary treatment works at Stonecutters Island, as part of HATS
![2001 -Full commissioning of HATS Stage 1 2001 -Full commissioning of HATS Stage 1](https://www.dsd.gov.hk/HATS_monograph/assets/images/2020/01/2001.png)
2001 - Full commissioning of HATS Stage 1
![2004 - Public consultation on the way forward for HATS conducted 2004 - Public consultation on the way forward for HATS conducted](https://www.dsd.gov.hk/HATS_monograph/assets/images/2020/01/2004.png)
2004 - Public consultation on the way forward for HATS conducted
![2009 - Commencement of works on HATS Stage 2A 2009 - Commencement of works on HATS Stage 2A](https://www.dsd.gov.hk/HATS_monograph/assets/images/2020/01/2009.png)
2009 - Commencement of works on HATS Stage 2A
![2011 - Cross Harbour Race returned in Victoria Harbour 2011 - Cross Harbour Race returned in Victoria Harbour](https://www.dsd.gov.hk/HATS_monograph/assets/images/2020/01/2011.png)
2011 - Cross Harbour Race returned in Victoria Harbour
![2012 -14 - Seven Tsuen Wan beaches reopened 2012 -14 - Seven Tsuen Wan beaches reopened](https://www.dsd.gov.hk/HATS_monograph/assets/images/2020/01/2012-14.png)
2012 -14 - Seven Tsuen Wan beaches reopened
![2014 - Breakthrough of deep tunnel system 2014 - Breakthrough of deep tunnel system](https://www.dsd.gov.hk/HATS_monograph/assets/images/2020/01/2014.png)
2014 - Breakthrough of deep tunnel system
![2015 - Full commissioning of HATS Stage 2A,Maiden Voyage for Clean Harbour 1 and Clean Harbour 2 2015 - Full commissioning of HATS Stage 2A,Maiden Voyage for Clean Harbour 1 and Clean Harbour 2](https://www.dsd.gov.hk/HATS_monograph/assets/images/2020/01/2015.png)
2015 - Full commissioning of HATS Stage 2A, Maiden Voyage for Clean Harbour 1 and Clean Harbour 2
![2016-18 -Numerous national and international awards won for the HATS project 2016-18 -Numerous national and international awards won for the HATS project](https://www.dsd.gov.hk/HATS_monograph/assets/images/2020/01/2016-18.png)
2016-18 - Numerous national and international awards won for the HATS project