Red and black may have Mephistophelian manifestations, but when the Red River turns black, a basic human right stares at a parched future.

Civilizations from time immemorial have flourished alongside rivers. From Mesopotamia, the land between the Tigris and Euphrates in 3500 BCE, and the Nile Valley in Egypt (3100 BCE) to the Indus Valley civilization around 2600 BCE, rivers have been an integral part of our existence.

A mighty river that gave birth to a civilization and the only one in the country named after a male deity, the Brahmaputra, has hit the headlines in recent days for having changed colour. This Red River, which originates in the Angsi glacier in Tibet as the Yarlung Tsangpo, enters Arunachal Pradesh as the Siang and Assam as the Brahmaputra before flowing into Bangladesh.

The Siang, the biggest river in Arunachal, is the cradle of the Adis. As the 2,900-kilometre long Brahmaputra, the river changed course several times and countless villages have fallen prey to its hungry tide, with homes, schools and hospitals swept under the swathe of current that no dyke, porcupine barrier or sandbag could withstand. As if that was not enough, the waters of the Siang and the Brahmaputra have turned turbid in recent days.

Last week, the Arunachal Pradesh Lok Sabha member, Ninong Ering, voiced concern over the Centre's statement that an earthquake in Tibet on November 17 had contaminated the Siang. The Union minister of state for water resources, Arjun Ram Meghwal, had parroted the Central Water Commission on December 3, saying that the Siang had turned black owing to the tremor in Tibet. Ering bristled at this "completely absurd" ratiocination. Echoing Meghwal, the Assam water resources minister, Keshab Mahanta, said: "We investigated samples of the Brahmaputra's water after getting reports that it had become highly turbid. The report revealed a high rate of soil ingredients."

Ering, however, countered: "The pollution of the Siang, where the permissible limit of nephelometric turbidity unit (NTU) is 0.5, has escalated to 425. The river is contaminated and all aquatic life has been destroyed. It is affecting livestock not only in Arunachal but downstream in Assam too. Migratory birds... have not been seen this year." He also wrote to the prime minister, Narendra Modi, highlighting reports of China constructing a 600 km tunnel to divert the Siang to the Taklamakan desert. China has, till Thursday, denied such a development, but few buy this stand. Miss Marple would possibly have checked if bottled water firms had any stake in this imbroglio!

As if the prospect of vanishing potability wasn't enough, the Brahmaputra's massive erosion has rendered thousands of villagers homeless. In the absence of any rehabilitation plan by the government, they moved to Assam's Amchang forest, the latest theatre of a massive eviction drive. Following a Supreme Court order, nearly 3,000 families in Amchang and 161 households in Karbi Anglong's Lahorijan reserve forest were evicted. Widespread protests have led to a two-month "rehabilitation" respite, but is that enough?

The Scheduled Tribes and Other Traditional Forest Dwellers (Recognition of Forest Rights) Act, 2006, says people who have been living in the forest from before December 13, 2005 need to be given land-occupancy certificates. The Amchang evictees had been living there since 1998 after losing their land to floods and erosion. Environmentalists, however, have greater ammunition: the National Forest Policy, Biological Diversity Act and Environment Protection Act, among others.

Isn't it ironical that in this man-animal conflict, elephants were deployed to dismantle human settlements illegally occupying animal habitat? Poetic justice rendered through a trumpet call!