Chlorine in tap water keeps it safe for direct drinking
We refer to Mr Zhang Jian’s letter, “Is Chlorine in tap water safe?” (26 Sep 2019).
Singapore’s tap water is perfectly safe for direct consumption and is well within the Guidelines for Drinking Water Quality set by the World Health Organisation (WHO). Raw water from reservoirs is conveyed to the waterworks where it is treated, filtered and disinfected. Treated water is disinfected with chlorine to remove all harmful bacteria and viruses. Residual chlorine in the water keeps the water germ-free and safe for direct drinking. This practise is in line with WHO’s recommendation to maintain a chorine residual throughout the distribution system to ensure water safety. The amount of residual chlorine in our tap water is well within the WHO’s limit of 5.0mg/litre.
Our tap water is suitable for drinking without the need for boiling or further filtration. PUB discourages the use of filtration devices as bacteria will grow on the filters if they are not kept clean, maintained or replaced regularly. To avoid misleading the public, suppliers and water filter companies are reminded not to make false claims on the effects of chlorine on humans and PUB water when promoting their products.
The public can be assured that PUB maintains a comprehensive water monitoring programme that starts from the raw water in the reservoir all the way to the customers’ tap, to ensure that only safe and clean water is supplied to the public. Over 450,000 tests are conducted annually on more than 300 parameters, surpassing some 130 parameters specified by the United States Environmental Protection Agency (USEPA) and the WHO. Water samples are taken daily from the distribution network and customers' taps at various locations throughout the island and tested to ensure that good water quality is maintained during distribution.
Members of the public can refer to PUB’s website or call PUB’s 24-hour call centre at 1800-CALL-PUB (1800-2255782) for more information.
Lim Mong Hoo
PUB, Singapore's National Water Agency