Water level has increased in River Tunga in Shivamogga.
Credit: DH File Photo
Bengaluru: The Karnataka State Pollution Control Board (KSPCB) has identified seven sources of pollution in the Tunga river, while the district administration is investigating encroachments along its banks.
According to a report submitted to the KSPCB, approximately 47.79 million litres per day (MLD) of sewage was generated in the river's catchment area as of December 2024, with a significant portion coming from Shivamogga city.
The seven identified pollution sources in Shivamogga district are Harakere, Uragadur, the stretch near Purle, Holebenavalli, Goravinakatte, SPM Road, and Thevarchatnahalli.
Officials noted that while the district has two sewage treatment plants (STPs) with a combined capacity of 46 MLD, only 14.52 MLD is being treated, leaving 33.27 MLD of sewage untreated.
Meanwhile, the Central Pollution Control Board (CPCB) submitted data to the National Green Tribunal (NGT), indicating that while faecal coliform levels were within permissible limits, the biological oxygen demand (BOD) reached a maximum of 8 mg/L — exceeding the permissible limit of 3 mg/L.
Dissolved oxygen levels ranged from 0.5 to 9.3 mg/L, with the lower end suggesting a high discharge of organic matter into the river.