Bitumen found in water supply of subsidised estate in Hong Kong’s Ma On Shan

Authorities have found bitumen in the freshwater supply of a Hong Kong subsidised estate, tracing the source of the sediments from a public pipe that underwent inspection last week.

The Water Supplies Department said on Thursday that it was alerted to the incident by the property management office of Kam Chun Court in Ma On Shan, involving blocks C, D and E.

Officers were deployed to collect and test water samples at the relevant flats and freshwater tanks in the buildings.

“The results show that all water samples comply with Hong Kong’s drinking water standards … After testing, the black particles were found to be bitumen, which is inert and not harmful to humans,” the department said on its social media page.

“We believe the particles resulted from a diversion of the water supply on September 12 to facilitate an inspection of an upstream public water main.

“During the process, the increased water pressure stirred up a small amount of sediment in the relevant service reservoir, prompting bitumen particles to enter the buildings’ internal water supply systems over the past few days.”