SHIVAMOGGA: A total of 693.75 km stretch of rivers across the state are polluted and water is being supplied to cities and towns from these polluted rivers.
Untreated water discharged from households in urban and rural areas is flowing into rivers, significantly degrading the quality of water. Arkavati, Lakshana Teertha, Tungabhadra, Bhadra, Tunga, Cauvery, Kabini, Kagina, Krishna, Shimsha, Bheema and Netravati are the polluted rivers and so far, 112 polluted drainages along these rivers have been identified.
Replying to an unstarred question from Thirthahalli MLA Araga Jnanendra in the Legislative Assembly during the winter session of the Legislature in Belagavi, Forest, Environment and Biodiversity Minister Eshwar Khandre said rivers are classified into five categories, P1 to P5, based on Biochemical Oxygen Demand (BOD) levels, with P1 being the most polluted.
Rivers with BOD levels above 30 mg per litre fall under the P1 category. Arkavati has been classified as P1, while no rivers fall under P2 and P3 categories. Tungabhadra, Bhadra and Shimsha are under P4, while eight other polluted rivers are classified under P5.
Khandre said domestic wastewater from municipalities, towns and villages along riverbeds is being discharged into at least 17 rivers, identified by the Central Pollution Control Board (CPCB).
This is the primary cause of river pollution, Khandre said.
He listed Mandya, Ramanagara, Vijayapura and Shivamogga districts, where drinking water is supplied from polluted rivers to homes. In parts of Uttara Kannada, Ballari, Vijayanagara and Bagalkot districts, polluted river water is used for water supply by local authorities. In 2022-23, CPCB identified South Pinakini, Aghanashini, Sharavathi and Gangavali rivers too as polluted. But wrote to CPCB, stating that these rivers are not polluted and sought their removal from the list. An action plan is being prepared for the South Pinakini river, he said.
On remedial measures, Khandre said the Karnataka State Pollution Control Board is setting up sewage treatment plants as per the directions of National Green Tribunal. Under 12 sanctioned river rejuvenation action plans, 817.31 million litres per day of sewage is generated in the state. Of this, 41 STPs with a combined capacity of 614.1 MLD have been installed, leaving 203.21 MLD untreated.
He said work is under way to set up 19 STPs with a capacity of 248.91 MLD, while 39 more STPs with a total capacity of 357.92 MLD are at the planning stage. Agencies are monitoring progress and submitting monthly reports to the NGT and consolidated reports to the Union Ministry of Jal Shakti. The state government gave its approval for underground drainage works worth Rs 535.56 crore in 2021 for 24 cities/towns besides Rs 523.80 crore for nine UGD projects.