Hong Kong enjoys one of the safest water supplies in the world. With the proper treatment and stringent quality monitoring and control, our water quality complies with chemically and bacteriologically to the Guidelines for Drinking-water Quality recommended by the World Health Organization (WHO).

The water quality throughout the supply system is continuously monitored by professionally qualified chemists under the Water Science Division of the Water Supplies Department through a series of physical, chemical, bacteriological, limnological, biological and radiological examinations.

Samples are regularly taken at intakes, storage reservoirs, water treatment works, service reservoirs, trunk-mains and consumers' taps to ensure that the water quality complies with the WHO guidelines. More than 100 000 water samples are taken and tested each year.

HOKLAS accredited by the
Hong Kong Laboratory Accreditation Scheme

Why is the World Health Organization Guidelines for Drinking Water Quality chosen?

The WHO Guidelines for Drinking-water Quality are the consensus opinion of over 490 leading experts from about 90 developed and developing countries, based on the latest worldwide scientific and medical information. The WHO Guidelines are authoritative, scientific, evidence-based and adopted by countries for setting national standards.

Apart from the Guidelines for Drinking-water Quality published by the WHO, there are of course other similar guidelines, such as the USEPA's (United States Environmental Protection Agency) and the EC's (European Community). There can be no direct comparison between these standards because regional standards are set in accordance with the characteristics of their respective raw water. Overall, the WHO Standard is representative of its kind.