Water supply and sanitation in Singapore are intricately linked to the historical development of Singapore. It is characterised by a number of outstanding achievements in a challenging environment with geographical limitations. Access to water in Singapore is universal, affordable, efficient and of high quality.
Innovative hydraulic engineering and integrated water management approaches such as the reuse of reclaimed water, the establishment of protected areas in urban rainwater catchments and the use of estuaries as freshwater reservoirs have been introduced along with seawater desalination in order to reduce the country's dependence on untreated imported water.
As a result of such efforts, Singapore has achieved self-sufficiency with its water supply since the mid-2010s. Examples include its "Four National Taps" for its water supply. Five desalination plants have been opened throughout the country since 2003, which in total are able to produce a maximum capacity of approximately per day.
Singapore's approach does not simply rely physical infrastructure, but it also emphasises proper legislation and enforcement, water pricing, public education as well as research and development. In 2007, Singapore's water and sanitation utility, the Public Utilities Board, received the Stockholm Industry Water Award for its holistic approach to water resources management.
Singapore was also the first country in Asia to institute a comprehensive fluoridation programme which covers the entirety of its population. The water was fluoridated at 0.7 ppm using sodium silicofluoride.
History
Early local water supply (until 1979) The history of common water supply in Singapore began with the construction of the MacRitchie Reservoir, which was built by the British in 1866.
During the drought of 1902 the Water Department cut supply to just 2–3 hours per day. Singapore faced a severe shortfall in water and stored water was estimated to be 70 million gallons, or less, against consumption of 2.5 million gallons per day. Evaporation from the reservoir made the situation worse and there were daily records of the falling water level in the reservoir.
There was public pressure to prioritise the town's water supply over 'shipping interests'. The leader writer in the Singapore Free Press Weekly recognised the needs of the port and shipping industry for fresh water had to be considered as 'most important' otherwise '[Singapore] may as well be shut up'.
Water meters were already in use in Singapore in 1902. In an article during the 'Water Famine' a householder complained of his meter whizzing round even though only air came through the pipe. The householder feared being charged the tariff (20 cents per 1,000 gallons or 4.4 cents per m3) but was assured by the Water Department that his bill would be corrected to the average consumption over previous months. The same article highlights that, in searching for water and drilling artesian wells, it was discovered that no geological survey of the island of Singapore had ever been undertaken.
Another faulty water meter resulted in a court case involving attempted bribery of a Water Department official. A large water consumer was convicted of offering a bribe to have his faulty water meter left alone and uncorrected.
Lower Peirce Reservoir and the Upper Seletar Reservoir were completed in 1913 and 1949 respectively, in order to supply the rapidly modernising colonial city with sufficient water. In 1927 the municipal leadership of Singapore and Sultan Ibrahim of the state and territories of Johor in neighboring Malaya signed an agreement that allowed Singapore to rent land in Johor and use its water for free. The Municipal Water Department, under David J. Murnane, began importing raw water from Gunong Pulai in 1927 and filtered water on 31 December 1929. The water filtration and pipeline capacity from Gunong Pulai was doubled in 1939.
In 1938, another pipeline was built to return a quantity of treated water to Johor. During the Fall of Singapore in 1942, the causeway that linked Singapore with the Malay Peninsula was blown up by retreating British troops to slow down the Japanese advance, thus destroying the pipeline, which left Singapore with decreased water reserves that could last at most two weeks. According to Lee Kuan Yew, this was one of his motives to envision water self-sufficiency for Singapore going forward when he became the country's first prime minister.
Expansion of water imports and of local reservoirs (1965–1997)