Editorial | Hong Kong must hasten water pipe replacement efforts

The government has swiftly responded to the situation this time, including providing a temporary water supply to affected residents and cleaning up the bitumen-polluted water tanks in Taikoo Shing, a large private residential estate in Quarry Bay. Residents in several blocks found a black substance in tap water last week after the Water Supplies Department carried out a temporary re-routing of the water supply near the estate to facilitate pipe maintenance works, resulting in changes in water pressure that might have stirred up sediments in the pipes. Investigations also found damage to one of the filter facilities at the estate’s public water inlet, which may have allowed sediments to enter the estate’s water pipes.

In June, black particles were found in the freshwater supply at two public housing estates, Queens Hill Estate and Shan Lai Court, in Fanling. Residents of Grand Promenade in Sai Wan Ho and Kam Chun Court in Ma On Shan also reported similar problems in July and September respectively. Officials are adamant that the substance, obtained from crude oil and used for its waterproof and adhesive properties in local water pipes until 2005, is not harmful to health. But they have conceded that the presence of such a material in the water supply would cause worries among the public.

Responding to the Queens Hill saga in June, Chief Executive John Lee Ka-chiu said the government had the responsibility to ensure the public could safely consume freshwater, adding that there would be a long-term replacement plan for bitumen-lined water pipes.

According to the authorities, about 230km or 3.9 per cent of fresh water distribution mains still have bitumen, which will be replaced or rehabilitated in phases, including some 70km included in a works programme over the next 10 years. The latest incident has added a sense of urgency to the replacement work.