“Drink the water, remember its source”, so the ancient Chinese maxim maintains.

As well as a metaphorical prompt to recall one’s sources of personal nourishment, this saying literally reminds us to keep a watch on water quality. This issue has become particularly important in Hong Kong, where pipe-caused lead contamination has become a slow-burning public scandal.

Water’s symbolic importance in Chinese culture partially evolved because the country was – and remains – critically short of this vital commodity. With rising prosperity, increased demand continues to overstretch supply in many locations. Water pollution, in step with unchecked industrial development and sprawling urbanisation, has only become worse in recent years.

Water supplies from certain wells, however, historically became known for their purity and health benefits.

Chinese folk beliefs maintain that the fabled Seven Celestial Sisters descend to Earth on the night of the seventh day of the seventh lunar month to bathe in certain wells. From contact with their divine bodies the water in these wells is believed to acquire magical properties, which can be transmitted to mere mortals.

Carefully gathered and stored, this water, allegedly, remains fresh for at least a year and has a range of benefits. Mixed with small quantities of salt, it is used to treat colds, sore throats and minor ailments.

The strength and potency of this water varies from well to well. Historically, when someone chronically ill was cured by drinking magical water sourced from a remote area without any agricultural or domestic contamination, that well’s miraculous reputation rapidly spread.

Folk beliefs about the spiritual cleansing effects of “holy water” transcend geography and cultures. Christian rituals of water baptism, performed to signify personal acceptance of a set of beliefs (whether this takes place as an infant or an adult varies from cult to cult), illustrates this point.

Muslims ritually bathe before each set of prayers; these rites vary from full-scale ablutions done five times a day in tropical places with plentiful supplies of water, such as Malaysia and Indonesia, to a near-symbolic anointment in the deserts of the Middle East and Central Asia. Hindus bathe in the waters of the River Ganges, in northern India. This legendary watercourse’s holiness varies by location; some stretches are, apparently, not sacred at all.

Varanasi (Benares) is the most favoured spot for complete spiritual renewal in this life, and the dispersal of human ashes after cremation ceremonies has long been conducted on the open riverbank.

From ancient times down to the present day, powerful religious institutions have made large sums of money from shrewdly commercialised waterrelated superstitions. Hong Kong’s plethora of Roman Catholic trinket shops sell bottles of “holy water” sourced from international religious sites, such as Lourdes, in southwestern France.

As for current local fears about widespread lead contamination in water supplies due to the use of inappropriate pipes, profit-motivated quality compromises are an established fact of life with Hong Kong’s building contractors.

As the public now realises, observing that age-old axiom remains of vital importance.

For more on Hong Kong history and heritage, go to scmp.com/topics/old-hong-kong