A popular Kannada adage says that drinking water from the Tunga is equal to taking a bath in the Ganga. However, the condition of the Tunga would make one balk at the idea of drinking its water, with untreated sewage from the Shivamogga City Corporation limits being discharged into it.
It was back in 2007 that the Karnataka State Pollution Control Board (KSPCB) filed a criminal case against the local urban body, which then filed an affidavit that it would set up a sewage treatment plant (STP). Tenders for it were floated in 2008–09 and the State government sanctioned ₹61.8 crore for the purpose. The STP with six aerated lagoons has come up, but it is yet begin functioning. Officials said this was because there is no money to complete the last stage of work.
While this is one of the starkest cases of pollution and official apathy, many rivers in Karnataka are polluted by untreated urban sewage.
In Hassan district, for instance, among the eight urban local bodies, five have installed plants to treat sewage. Sakleshpur Town Municipal Council has been releasing sewage into the Hemavati, the lifeline of Hassan people. Similarly, Alur and Arkalgud urban local bodies do not have sewage treatment plants.
The continuous monitoring of major rivers in Karnataka indicates that domestic sewage continues to be the single largest source of pollution, and if left untreated could choke the river flow. Water samples drawn from a few rivers, including the Lakshmanatirtha, Cauvery and Arkavati at certain stations, conform to ‘Class E’ as per environmental norms and hence are fit only for irrigation or industrial cooling.
Under the National Water Quality Monitoring Programme, 63 stations, covering 19 rivers, are being monitored by the KSPCB and the Central Pollution Control Board (CPCB) under the Global Environment Monitoring System (GEMS – five locations) and the Monitoring of Indian National Aquatic Resources System (MINARS – 58 locations).
Though quality of water along maximum stretches of the rivers in the State conforms to ‘Class C’ (fit for drinking only after treatment and disinfection), pollution owing to untreated sewage flowing into the rivers is on the rise.
Prakash, Environmental Officer, KSPCB, Mysuru, told The Hindu that water samples are analysed for physico-chemical and bacteriological parameters and what has been found along the Cauvery is the increasing withdrawal of relatively clean water from the river for human use and replenishing it with untreated sewage. This is a pattern consistent across other rivers of the State.
As per the report on the Status of River Water Quality in Karnataka from 2005–15, only 2.5% of the river quality conforms to ‘Class A’ (could be a drinking water source without conventional treatment, but after disinfection). However, these vary from month to month, depending on the flow; and the river tends to be relatively cleaner when there is an increase in the volume of water, leading to dilution of pollutants, and the converse when the flow is less.
The degradation of river water because of untreated domestic sewage is so high that portions of major rivers in the State have been designated as ‘Polluted river stretches’ by the CPCB, according to the report. These stretches are along the Tunga, Bhadra, Tungabhadra, Lakshmanatirtha, Kali, Krishna, Arkavati, and Malaprabha.
(With additional inputs from Sathish G.T. in Hassan.)
