Water quality in Cauvery, Bhavani, Tamirabarani improves
Besides them, Sarabanga, Vasistha and Thirumanimutharu have also shown improvement
Mettur dam
CHENNAI: Cauvery, Bhavani and Tamirabarani rivers will soon be removed from the list of polluted river stretches (PRS), as the water quality in these rivers has improved up to bathing standards. Besides them, the water quality in Sarabanga, Vasistha and Thirumanimutharu rivers has also improved significantly.
According to a report submitted by Chief Secretary Shiv Das Meena to the National Green Tribunal (NGT), the biological oxygen demand (BOD) was recorded at 3 mg/L in Cauvery and Bhavani in October 2023. Tamirabarani recorded a BOD level of 2.5 mg/L.
To put this improvement in context, the BOD level for Cauvery, Bhavani and Tamirabarani was 17, 4.6 and 7.5 mg/L, respectively.
BOD level up to 3 mg/L is considered as bathing standard, while any value above that is considered as pollution.
In 2018, the Central Pollution Control Board (CPCB) identified six polluted river stretches such as Cauvery, Bhavani, Tamirabarani, Sarabanga, Vasistha and Thirumanimutharu, and recommended measures to improve the water quality of the rivers.
Shiv Das Meena told NGT that action plans have been prepared for six PRS in coordination with line departments such as Municipal Administration and Water Supply, Chennai Metropolitan Water Sewerage and Sewerage Board, Directorate of Municipal Administration, Greater Chennai Corporation, Commissionerate of Town Panchayats, Rural Development and Panchayat Raj and Water Resources Department.
“The action plans for Rivers Sarabanga, Thirumanimutharu, Vasistha, Cauvery, Bhavani and Tamirabarani have been approved by the CPCB and are under implementation by the line departments,” he added in the report.
Due to the continuous efforts of the State government on rejuvenating the polluted rivers, the PRS priorities for Sarabanga, Cauvery and Bhavani rivers have been shifted to lower priorities during the year 2022. Hence, Sarabanga, Cauvery, Tamirabarani and Bhavani will be eliminated from PRS list early, he said.
Apart from Cauvery, Bhavani and Tamirabarani, the BOD levels of Sarabanga, Vasistha and Thirumanimutharu have also improved. In October, the BOD levels of the rivers were 12, 6 and 7 mg/L, respectively. As per the 2018 report, BOD levels were 24 mg/L in Sarabanga, 56 mg/L in Thirumanimutharu and 230 mg/L in Vasistha river.
