Are heavy metals being dumped into the Vrishabhavathi river by industries on the sly? Recent findings from a year-long study involving monthly 24-hour sampling by researchers of Ashoka Trust for the Environment and Ecology (ATREE) pointed to illegal discharge from industries at night. Researchers found big peaks in heavy metal levels between midnight and early morning.
This is despite Karnataka State Pollution Control Board (KSPCB) mandating ‘red category’ industries to use effluent treatment plants and not discharge any water into external outlets.
The fact that the illegal discharge occurred at night was attributed to the elevated levels going unnoticed by KSPCB staff who usually collect samples during the day.
The researchers started by probing the nature, sources and impact of the waste water-based irrigation in the Vrishabhavathi valley.
They collected water samples from three villages downstream of Byramangala tank.
Analysis revealed contamination, particularly of heavy metals such as nickel, copper, chromium, lead and manganese, which had seeped into the soil, groundwater as well as milk and vegetables. At risk was not only to the local population, but also the urban people who would ultimately consume the food.
The researchers also found that farmers had shifted from cultivating ragi and maize to corn and fodder for the dairy industry.
Monitoring the Peenya stream at multiple points and mapping potentially polluting industries and facilities not listed in the KSPCB database revealed that at least 50 per cent of the heavy metal loads were coming from the Peenya Industrial Area and other designated industrial areas nearby. However, Venkatesh D.T., immediate past president of Peenya Industries’ Association, said the allegations were false as all effluents were being treated and used by the industries. “We are also in the process of setting up a common effluent treatment plant to cater to 250 to 300 units. We also have a water task force,” he said.
KSPCB Chairman Lakshman said though there had been instances of illegal effluent discharge, that was about four years ago. “We have asked our field assistants to conduct random checks at night as well. If they are found to be violating the rules, we will close the industrial unit. We have also called the Peenya Industries’ Association on August 16 to discuss the issue,” he said.