"The hygiene of potable water is as vital, if not more so, as food safety is to people in daily life," said Wei Xiangdong, an official with the Beijing Health Supervisory Office.

With fast urbanization, more and more water supply facilities have been built, extended or reconstructed, which have brought many potential hazards to water safety, Wei said.

In 1997, the city issued a sanitation supervisory and management regulation on potable water for domestic purposes, stipulating requirements for drinking water quality, water infrastructure and facilities, as well as personnel involved in water supply.

Sustained inspections by the city's health supervisory authorities during the past five years indicate that the quality of drinking water generally meets the standards outlined by the regulation.

However, there are still some water supply operations that have been put into operation without licences from health authorities. As a result, they often fail to assure water safety, Wei said.

The city's potable water supply system consists of four parts - municipal water works, secondary water supplies for high-rise buildings, self-sunk wells and simple tap water supplies in the countryside.

Due to limited hydraulic pressure, water from public works is unable to travel up to stories higher than the sixth floor. A high-rise building therefore needs a separate water supply system to pull water to the top and distribute it to each apartment. This is called secondary water supply.

This kind of water supply may have hazards and is a primary concern for health workers.

(China Daily June 13, 2002)