A national water quality survey conducted under the Central Pollution Control Board’s National Water Quality Monitoring Programme has revealed that nearly half of the wells tested in 10 districts across Kerala are contaminated. Of the 31 wells sampled in October 2024, 16 showed varying degrees of contamination, raising serious concerns over groundwater safety.
Districts where the wells were tested include Thiruvananthapuram, Kollam, Alappuzha, Kottayam, Ernakulam, Malappuram, Thrissur, Kozhikode, Palakkad, and Kannur. The Kerala State Pollution Control Board, which conducted the tests, flagged several wells for immediate investigation to ensure public health safety.
Particularly alarming were a few samples with extremely high Most Probable Number (MPN) values ranging from 400 to 4000 indicating significant faecal contamination likely linked to poor sanitation infrastructure. In contrast, 15 samples were within acceptable or low-risk levels.
The findings were submitted by the Kerala government to the National Green Tribunal (NGT) in a report on the state’s solid and liquid waste management. The tribunal had asked for detailed data on groundwater quality in areas where septic tanks are commonly used for sewage disposal.
The report also noted the likelihood of contamination in regions with improper containment systems. In response, urban and rural local bodies have been directed to retrofit faulty septic systems and ensure new constructions meet containment standards such as installing lined or leak-proof tanks developed by DRDO or other approved models.
Authorities have also been asked to organise behavioural awareness campaigns, targeting households, builders, and sanitation workers. Regular groundwater monitoring will now be required in affected areas, with support from the State Groundwater Department and research bodies to mitigate contamination risks.