Owing to rapid urbanisation in most parts of the state, sewage is generated in Karnataka cities at the rate of 3356.5 MLD (million litres per day), of which only 45 per cent (1513.5 MLD) is treated, said a report.
The Central Monitoring Committee set up by the National Green Tribunal to study and suggest remedial measures to check river pollution in the state, stated this in its report submitted to the Green Bench. It stated that even though 125 sewage treatment plants are installed in Karnataka to treat 2,242 MLD sewage water, only 1513.5 MLD treated while the remaining 1,843 MLD is not treated.
Only 427.5 MLD treated water is being reused in Bengaluru city, while 106.65 MLD treated water is being used in areas other than Bengaluru city. Treated water is used mostly for recharge of lakes, industrial establishments, by horticulture departments and for gardening, said the report.
In the state, a total of 3,503 industries generate 1,339 MLD polluting water, of which 3,289 industries have set up effluent treatment plants having the capacity to treat 4,532 MLD polluted water.
Total 17 river stretches have been identified as 'pollutant stretch' in the state, in which Tunghabhandra river has been selected for model development of rejuvanation.
In the entire country, 48,004 MLD of sewage (from urban settlements) was being generated in 31 States/ UTs. These states set up sewage treatment plants with 30,001 MLD capacity, which can treat only 62 per cent of the total sewage. However, against the existing capacity, only 56 per cent was being utilized, said the report.
The capacity utilisation of STPs was highest in Andhra Pradesh (90%) and Delhi (90%), followed by Telangana (82%) and Punjab (80%). Assam does not have any existing treatment capacity while Tripura and Manipur has only one STP each.
"States must ensure optimum utilization of the existing treatment infrastructure and also ensure compliance of the plants with regard to the environment norms. For this purpose, States may carry condition assessment studies of existing STPs/ sewage infrastructure in a fixed time frame, say another 3 months so as to identify the reasons of suboptimum utilization and dysfunctionality of existing STPs. This will help them in finalizing plans to upgrade STPs requiring upgradation so as to make them functional," said the report.