A water main damaged during road works on Shau Kei Wan Road on October 27 interrupted supplies in Shau Kei Wan and parts of Sai Wan Ho. Repairs were completed and water supply resumed that evening. In the days that followed, residents reported black particles in their tap water.
On November 3, residents posted online about black material and low water pressure. HK01 reported that some household filters quickly turned black; some residents also told the outlet they had sore throats after drinking the water or that their skin worsened after washing their faces.
The Water Supplies Department said the particles came from asphalt used to line the inside of steel pipes in the upstream government supply network. It said flushing after the repair disturbed the lining and carried sediment downstream. Changes in water flow and pressure during flushing could also lift sediment from government pipes or buildings’ internal supply systems.
The department tested samples from the government network and buildings’ internal systems. Some contained small amounts of sediment, including inert asphalt, but all met the Hong Kong drinking-water standard. It said the water would not affect public health.
It had increased flushing of government pipes and filters and was helping buildings flush internal systems, clean water tanks and clear sand filters. Water trucks and tanks had been placed nearby where buildings needed temporary supplies. After treatment, supplies had returned clear and sediment was becoming less common in the area.
The department advised residents to remove tap aerators and run the water for several minutes until it ran clear before replacing them. If water had been sitting in pipes for some time, it advised running the tap until clear before drinking.
Improvement works on the affected section of water main began in October 2025. Temporary pipes are being laid along the affected stretch, and the department aims to make a temporary connection by the end of 2026. Permanent improvements are expected to be completed in January 2028.