Water supply and sanitation in Singapore are intricately linked to the historical development of Singapore. It is characterised by a number of achievements in a challenging environment with geographical limitations. Access to water in Singapore is universal, affordable, efficient and of high quality. 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.