Poor water quality in five river basins in India
Sewage contamination, dumping of waste, and salinity intrusion have contributed to the poor water quality in five river basins in the State, raising concerns about the health hazards for people and highlighting the need for proper management of water resources.
A study conducted by the Centre for Water Resources Development and Management (CWRDM) has revealed that most of the water samples collected from the Muvattupuzha river basin in Ernakulam and Kottayam districts, Vamanapuram basin in Kollam and Thiruvananthapuram districts, Peruvamba basin in Kannur, Kariangode river basin in Kasaragod and Korapuzha basin in Kozhikode district are high in bacterial contamination, especially during the monsoon season.
The study was part of an environmental monitoring programme on water quality funded by the Kerala State Council for Science, Technology and Environment (KSCSTE).
Surface water samples collected from all the 19 stations in the Muvattupuzha river basin were of poor quality, mainly due to waste dumping and saline water intrusion. Groundwater samples showed high E.coli contamination.
Biological analysis of water samples showed moderate organic pollution, indicating the vulnerability of the river to various anthropogenic activities.
In the Vamanapuram river basin, 87 per cent of the surface water samples had marginal water quality while 13 per cent showed poor quality. High E.coli count was recorded in 80 per cent of the samples. The bacteriological contamination was maximum during the monsoon season.
Sediment analysis showed that all the sites along the Vamanapuram river except the Kallar bridge were heavily polluted with nickel. The report concludes that sewage effluents and agricultural activities downstream had impacted on the quality of the river water.
As many as 88 per cent of the surface water samples from the Kariangode river basin and 71 per cent of the samples from Peruvamba tested positive for E. coli during the monsoon.
All the stations in the Kariangode basin and most of those in the Peruvamba recorded poor water quality. Sediment samples from the Kariangode basin were found to be heavily contaminated with lead and nickel.
All the stations in the Korapuzha basin registered poor water quality. Total coliform and faecal coliform levels were high throughout the year.
Ground water samples also showed high levels of E. coli.
Suresh Das, Executive Vice President, KSCSTE, said the data generated by the study would be used to formulate programmes for mitigating the anthropogenic impact on the rivers.