A major river in the New Territories has turned a bizarre shade of blue-ish green in recent weeks, but the government says sample tests detected no abnormalities in water quality.
In a letter sent to Sha Tin district councilors last week about the color change observed at Shing Mun River, the Environmental Protection Department (EPD) said inspections had been conducted at the concerned sections of the channel.
The department said that tests did not find any illegal discharge, but did not explain what caused the color change.
About an 800-meter stretch of the Shing Mun River near Tai Wai station turned murky green in late January, alarming nearby residents who said they spotted an oily substance and white foam floating on the river.
A picture posted to social media on Jan. 24 showed dozens of dead fish drifting along the riverbank. “The entire Shing Mun River is filled with dead fishes,” the Facebook user wrote.
It’s not the first time that Shing Mun River, a 7-km channel that runs through the Sha Tin District, has changed color.
In 2015, a tributary near Fo Tan, an industrial zone, turned bright blue, prompting concern over water pollution. In 2018, the same section turned a sharp shade of green. The EPD attributed the color change to fluorescent powder that workers at a nearby industrial building had used, according to Apple Daily.