Hong Kong's fresh water supply complies with quality standards and is stringently monitored daily.

This was the message today from the Water Supplies Department in response to press enquiries on whether the quality of Dongjiang water will be adversely affected by reported effluent from a factory at Huizhou.

The department said sampling tests in the last six months consistently show the concentrations of cadmium, chromium and zinc in the raw water from Guangdong were less than 0.001 mg/L, 0.002mg/L and 0.01mg/L. The levels are well within the Environmental Quality Standards for Surface Water.

The department said the standard is specified in the raw water supply agreement between Guangdong and Hong Kong, adding that monitoring will be stepped up if a rise in the concentration of any heavy metals is detected.

It has approached Guangdong authorities for more information on the Huizhou factory issue, particularly as to whether the effluent will adversely affect water quality.

Drinking water supplied by the department complies with the World Health Organisation Guidelines for Drinking Water Quality. The data can be viewed on the department's website.