Robot to clear tank sediment without stopping water supply

Residents reported black residue after roadworks damaged a pipe; the Water Supplies Department says samples met Hong Kong’s drinking-water standard.

By newsdesk · 10 November 2026, 15:12 HKT

Reporting: i-CABLE News · Commercial Radio

The Water Supplies Department is using a dedicated robot to remove sediment from building water tanks without stopping the water supply. The department says one or two operators can run the machine.

Residents reported black sediment in their tap water after a water pipe was damaged during roadworks on Shau Kei Wan Road in late October. The department said sediment entered building tanks and attributed the residue to flushing after repairs, which stirred the pipe’s asphalt inner coating. It said samples met the Hong Kong drinking-water standard and the sediment did not affect public health.

Traditional tank cleaning requires the water to be stopped and the tank emptied before workers enter to clean it. The department says the process can take longer and affect residents’ water use.

If sediment remains after running indoor taps, the department advises residents to contact their building management or call its customer-service hotline on 2824 5000.