International Agreement

Imported water is the 2^nd national tap that helps Singapore increases the water supply. It is to have an agreement with countries that have an abundant supply of water.  Called the Johor River Water Agreement, it was signed on 29 September 1962 between the Singapore city council and the Johor state government. Valid for 99 years up till 2061, it gave Singapore the full and exclusive right to draw water from Johor River up to a maximum of 250 million gallons per day (1.14 million cubic metres a day). In return, Johor was entitled to a daily supply of treated water from Singapore up to 2% of the raw water it supplied. The Independence of Singapore Agreement (also known as the Separation Agreement) signed between the governments of Singapore and Malaysia on 9 August 1965 guaranteed the 1961 and 1962 water agreements. This was signed on 24 November 1990 between the Public Utilities Board (PUB) of Singapore and the Johor state government. It was supplementary to the 1962 pact and would also expire in 2061. The advantage is that it’s convenient and cheap in comparison with NEWater and Desalination.

 However, its disadvantage is that it’s unreliable as compared with other water sources as Johor might not want to provide Singapore with water without notice.

Source: http://infopedia.nl.sg/articles/SIP_1533_2009-06-23.html