Banar River in the north central Bangladesh district of Mymensingh bleeds red, black, blue, maroon and sometimes milk-like white, thanks to untreated industrial waste discharge from a lone factory into the water.
The dirty rainbow on the stream frightens locals of Trishal upazila in the district. Time was when they used the water for irrigation, household chores and cattle rearing.
"We used to cultivate winter crops by the river. But yields have dropped in recent years due to the pollution," said Chan Mia, a local farmer.
He said villagers used to grow paddy saplings on the river bank, but that is now a distant memory.
"A dozen ducks died recently after they waddled into the river for food," Kamal Hosen, another local, told The Business Standard. He said he now keeps his birds and cattle out of the toxic water.
The stream falls into Mymensingh's Khiru river, and the flow eventually ends up in the Sitalakhya.
Villagers who used to depend on the river for fishes once said the industrial pollution is sweeping away fishes and other aquatic species.
"There had been at least 30 fish species in the river and adjacent water bodies during the monsoon even a decade ago. Fishing together was like a festival for us. But those days seem to have gone forever," said Abdul Karim, a villager who lives by the river.
Water colour changes even twice a day
On 16 October, the river was red under the Banar bridge of the Dhaka-Mymensingh highway. There was no change in the blood-like colour of the water for as far as one could walk for hours along the river bank.
The next day, however, the water appeared to be brown at the same point.
Abdul Barek, a resident of the local Amirabari union, said he had been observing the changing colour of the water for a long time.
"We often see one colour in the morning and another in the afternoon," he commented.
A seven-kilometre walk up river led to the discovery of a narrow canal from which light maroon water was gushing into the river.
Upstream of the canal, locally known as "Chauhar Khal", water colour was normal – suggesting the canal will lead to the polluter.
The canal was found carrying industrial waste from Dresden Textiles Ltd, an apparel making unit on the riverbank. Nure Alam Khokon, an assistant general manager of the factory, said the factory does not have an effluent treatment plant (ETP).
Requesting that there be no report on the misdeed committed by the management, he claimed the factory would set up an ETP soon.
Farid Ahmed, director at Environment Directorate, Mymensingh Division, said a notice on river pollution had been served on the company earlier.
"As far as I remember, the factory's drainage into the river had been put to a stop. But since they are polluting the river again in defiance of the directorate's ban, action will be taken," he added.
However, Advocate Shibbir Ahmed Liton, a member of the local river protection committee, was critical of the role of the directorate. In his view, the authorities must answer the question of how the factory could continue its operations in full view of the directorate.
"If immediate action is not taken, we will take to the streets," he warned.