| Year | Events |
|---|---|
| 1851 | Five wells sunk for City water supply. |
| 1860 | Tanks constructed at Bonham Road. |
| 1863 | Pok Fu Lam reservoir with a capacity of 9,000 cubic metres and aqueduct completed. |
| 1871 | Second Pok Fu Lam reservoir with a capacity of 26l,000 cubic metres completed. |
| 1874 | Mint dam and Blue Pool dam re-constructed. |
| 1877 | Conduit constructed to convey water from Pok Fu Lam reservoir to City. |
| 1889 | Original Tai Tam scheme for City waterworks completed. |
| 1890 | First filter-beds constructed at Albany. |
| 1891 | The Peak supplied by City waterworks by pumping. |
| 1892 | City waterworks distribution completed. |
| 1895 | - Total capacity of storage reservoirs increased to 1.74 million cubic metres. - Kowloon waterworks to supply 1,136 cubic metres per day opened. |
| 1897 | Tai Tam dam raised to bring the total storage capacity to 2.17 million cubic metres. |
| 1899 | Wong Nai Chung reservoir completed. Total storage capacity increased to 2.32 million cubic metres. |
| 1902 | Water shortage in the spring. Water brought in by lighters from Tsuen Wan to the Hong Kong Island. Kowloon Waterworks started. |
| 1904 | Tai Tam Byewash reservoir increased City storage capacity to 2.44 million cubic metres. |
| 1906 | Kowloon reservoir brought into use. |
| 1925 | Shek Lei Pui reservoir completed. |
| 1930 | Water first delivered from Kowloon to the Hong Kong Island by a 300-millimetre diameter submarine pipeline under the harbour. |
| 1931 | Kowloon Byewash reservoir completed. |
| 1936 | Shing Mun Valley (Jubilee) reservoir completed. |
| 1939 | With the exception of the Shouson Hill area all water on the Hong Kong Island and in Kowloon urban area filtered. |
| 1946 | Water supply re-established almost to the pre-war standard. |
| 1957 | Tai Lam Chung reservoir completed. |
| 1960 | - Work started on Plover Cove reservoir, the first fresh water reservoir in the world to be carved out of the sea. - First Agreement reached with Guangdong authorities for supplies from Guangdong. |
| 1963 | Shek Pik reservoir on Lantau Island completed. |
| 1964 | Sha Tin water treatment works Stage I with a capacity of 364,000 cubic metres per day commissioned. |
| 1965 | Second Agreement reached with Guangdong authorities for incremental supplies from Guangdong. |
| 1968 | Plover Cove reservoir with a capacity of 170 million cubic metres completed. |
| 1971 | The government decided to embark on the High Island Scheme. |
| 1973 | Dam raising for Plover Cove reservoir completed, bringing the capacity to 230 million cubic metres. Hong Kong's storage capacity trebled. |
| 1975 | The first of the six 30,300 cubic metre-a-day units of the Lok On Pai Desalter came into operation. |
| 1978 | - High Island reservoir, with a storage capacity of 281 million cubic metres, completed. - Third Agreement reached with Guangdong authorities for further incremental supplies from Guangdong. |
| 1980 | Amendment to Third Agreement reached with Guangdong authorities for further incremental supplies from Guangdong up to 620 million cubic metres per annum by 1994/95. |
| 1982 | Shut down and moth-balling of Lok On Pai Desalting Plant. |
| 1983 | - First glass reinforced plastic water main completed, having a diameter of 2.2 metres and a length of 3.5 kilometres for conveyance oF water from Guangdong. - Sha Tin water treatment works last stage completed, bringing the total capacity to 1.23 million cubic metres per day, the largest water treatment works in Hong Kong. |
| 1985 | Yau Kom Tau water treatment works stage I completed, the first water treatment works using modern direct filtration technology with a daily throughout of 160,000 cubic metres. |
| 1986 | Sheung Shui water treatment works stage I with a capacity of 100,000 cubic metres per day commissioned. |
| 1987 | - Fourth Agreement reached with Guangdong authorities for further incremental supplies from Guangdong up to 660 million cubic metres per annum. - Implementation of Regionalization for the Supply, Distribution and Consumer Services activities. |
| 1989 | - Fifth Agreement reached with Guangdong authorities for further incremental supplies from Guangdong up to a maximum quantity of 1,100 million cubic metres per annum. - Pak Kong water treatment works stage I with a capacity of 273,000 cubic metres per day commissioned. |
| 1990 | All mechanical and electrical workshop facilities were centralized in the Mechanical and Electrical Workshop at Lung Cheung Road and Bullock Lane Depot was handed to Urban Council for recreational development. |
| 1991 | Lok On Pai Desalting plant demolished. |
| 1992 | - Pak Kong water treatment works stage II completed, bringing the total capacity to 800,000 cubic metres per day, the second largest water treatment works in Hong Kong. - Au Tau water treatment works stage I with a capacity of 110,000 cubic metres commissioned. |
| 1994 | Muk Wu 'C' pumping station commissioned, the largest pumping station in Hong Kong. |
| 1995 | - Yau Kom Tau water treatment works stage II completed, increasing the capacity to 250,000 cubic metres per day. - Sham Tseng water treatment works stage I completed, the first water treatment works using Dissolved Air Flotation method for water clarification. - Tai Po Tau 'D' pumping station commissioned. - Au Tau water treatment works stage II completed, bringing the total capacity to 330,000 cubic metres per day. |
| 1996 | - Sheung Shui water treatment works stage II completed, bring the total capacity to 200,000 cubic metres per day. - Siu Ho Wan water treatment works stage I with a daily capacity of 150,000 cubic metres completed. |
| 1997 | Ma On Shan water treatment works with a daily capacity of 227,000 cubic metres completed. |
| 2000 | - Customer Telephone Enquiry Centre put in operation. - Sham Tseng water treatment works stage II completed, increasing the daily capacity from 23,000 cubic metres to 36,500 cubic metres. - Ngau Tam Mei water treatment works stage I completed, the first water treatment works using ozone and biological filters with a daily capacity of 230,000 cubic metres. |
| 2003 | - Tai Po water treatment works stage I with a daily capacity of 250,000 cubic metres completed. - The dedicated aqueduct system under the "Dongshen Water Supply Improvement Works" projects completed. |
| 2004 | Pilot desalination plant at Tuen Mun Salt Water Pumping Station with a Reverse Osmosis (RO) production of water at 240 cubic metres per day commissioned for trial run. |
| 2006 | - A new agreement reached with Guangdong authorities for the first-time implementation of a flexible arrangement for Dongjiang water supply based on the actual needs of Hong Kong. - The pilot desalination plant was relocated from Tuen Mun to Ap Lei Chau for further trial test under different sea water environment. |
| 2008 | A new agreement for the supply of Dongjiang water to Hong Kong was signed. The agreement guaranteed a stable yet flexible supply of Dongjiang water for the period from 2009 to 2011 based on the actual needs of Hong Kong. |
| 2009 | - 41 Historic waterworks installations at Pok Fu Lam, Tai Tam, Wong Nai Chung, Kowloon, Shing Mun and Aberdeen were declared monuments. - The first two service reservoirs built in a cavern - Western Salt Water Service Reservoir and Western No.2 Salt Water Service Reservoir were commissioned. |
| 2011 | - A new agreement for the supply of Dongjiang water to Hong Kong was signed. The agreement guaranteed a stable yet flexible supply of Dongjiang water upto 2014 based on Hong Kong’s actual needs. - Expanision of Tai Po Water Treatments Works - Part I works completed, bringing the daily capacity of the plant increased from 250 Mld to 400 Mld. |