Dhansiri: River of Life

Pollution Concerns: Environmentalists have alerted the Central Pollution Control Board (CPCB) about alleged hazardous effluent discharge from Numaligarh Refinery Limited (NRL) into the Dhansiri River.

Ecological Damage Warning: Concerns highlight the potential for severe ecological damage to the river due to the effluent.

AGT Biosciences Report: A report by AGT Biosciences indicated that water samples from NRL’s effluent plant exceeded CPCB discharge standards for petroleum refineries.

Exceedance of Standards: The report showed Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), and oil & grease content exceeding permissible CPCB limits. BOD recorded at 18.0 mg/L (limit 15 mg/L), COD at 142.0 mg/L (limit 125.0 mg/L), and oil/grease at 11.5 mg/L (limit 10 mg/L).

Threat to Biodiversity: The exceedances are considered a pattern of pollution, endangering the Dhansiri River’s biodiversity and dependent communities.

BOD Impact: High BOD levels deplete dissolved oxygen, crucial for aquatic life.

River’s Importance: The Dhansiri River is a significant tributary of the Brahmaputra, originating in Nagaland and flowing through Assam.

Flora and Fauna: It forms the Nagaland-Assam border harboring rich flora and fauna like Dhansiri Reserved Forest and Intanki National Park.