The Sundarbans, on the southern fringe of West Bengal, may soon struggle to provide quality drinking water to its human and non-human residents. This is because its ground water level has been plummeting steadily in recent years due to unbridled, and largely illegal, extraction of groundwater, according to a new study.
The decade-long study was carried out by local non-profit Joygopalpur Gram Vikash Kendra with UBU-Danish Association for Sustainable Development and Danish Technical University in several parts of the vast delta.
Researchers found that there has been a sharp decline in the water level of the Basanti block — in the range of 1 to 2 metres per year on average — over the last decade.
Environmentalists called for urgent action to turn the tide for an area already struggling with saline water ingress due to a series of cyclones and other weather disasters, according to an ongoing IIT Kharagpur study. “Our study shows that after each major extreme weather event in the area, saline water has penetrated more into the Sundarbans’ ground water table, increasing water insecurity,” pointed out Abhijit Mukherjee, a groundwater expert from IIT Kharagpur and a Bhatnagar award winner.
The study conducted in the Basanti block found, and this correspondent corroborated recently through an on-ground investigation, that a humongous amount of water lifted actually gets sold for irrigating paddy during the dry season. Locals do not often get water from handpumps as it recedes steadily and without any permission from the competent authorities.
On World Water Day (March 22), more than 500 people — mostly women — from the Basanti block came onto the roads. They protested the illegal practice and demanded that it be stopped at the earliest.
“Please share details of the violations with me. I am asking the state water investigation department and district administration to undertake an immediate enquiry and report to me so that I can take urgent action,” West Bengal’s minister of irrigation and waterways Manas Bhuniya told this correspondent on March 22 morning, upon hearing the complaint.
The water level monitoring project has garnered data since 2014 from 6 of the 19 blocks in the Sundarbans spread over 12 Panchayats. Nearly 70 per cent of the tubewells in these areas get dried up during the summer months up to varying degrees, it found. The trend is only increasing as time passes.
“Analysis of climate change data from the project villages since 2014-15 shows that nearly 70 per cent tubewells dried up during the summer months. The water level in some of the tubewells receded up to 9 metres. The analysis of low and high tide data shows that the water level is consistently increasing,” said Biswajit Mahakur, secretary of Joygopalpur nonprofit, who handles the water monitoring programme locally.
Incidentally, the Centre admitted in Parliament a few years ago that the country’s highest sea level rise is happening in the Sundarbans.
Henrik Bregnhoj, Technical University of Denmark professor and project lead, explained the results in detail to this correspondent.
“We have been working in several blocks but have consistently generated data from 30 wells in Basanti which we have measured regularly since 2014-15. Our data shows that the ground water level has been plunging about 1 metre every year around Jharkhali. But the figure is 2 metres in areas like Nafarganj and Jyotishpur,” stated the expert.
“Analysis of data shows that in areas like Jyotishpur, the lowest point of water was 10 metres in 2017, which nosedived further to 24 metres in 2024. The huge extraction of water for paddy irrigation in summer is the main cause,” said the Danish academic. He added that his team is now planning to use remote control monitoring to have a more micro-level assessment.
The analysis shows that in the summer months, irrigation accounts for 70 per cent of the water extracted while pipeline supply, rooftop pumping and handpumps cover the rest. “Unless you minimise the water draw from irrigation, there can soon be a drinking water crisis in the summer months,” said another expert associated with the project.
Shallow or submersible pumps — numbering hundreds in some Gram Panchayat areas — are drawing ground water regularly, most of which gets sold at a high price.
According to a primary study carried out by Joygopalpur, Basanti block itself has 783 shallow wells. Most of the water in them is sold for irrigation and some for drinking.
“As per our 2024 assessment, 783 shallow pumps draw 28 million litres of ground water daily for about three months in summer mainly for boro paddy crop irrigation. Most of these pumps irrigate around 30 bighas of agricultural land, including at least 20 bighas for which water is sold,” said a researcher from the nonprofit. A rough estimate shows that the illegal business covers nearly Rs 3 to 4 crore every year, a part of which is believed to go to a section of local political and administrative networks, alleged activists.
This correspondent has found that more than a hundred such clandestine pumps are operating openly in areas like Jyotishpur, Jharkhali and elsewhere in Basanti. “We work with verbal permission from local leaders and authorities and have taken clearance for electricity,” claimed one of the pump owners, not wanting to be named.
“We have not given any permission for commercial use of ground water,” said a local official, but did not respond when quizzed on how such an illegal money-spinning water business was being openly carried out.
“We have found that the rapid water withdrawal from shallows by private citizens, and pump houses run by the government, is responsible. Incidentally, nearly 50 per cent of the pump house water gets wasted for a range of reasons. This had led to a complete drying of 621 of 3,183 hand pumps used by common people,” added the nonprofit researcher. Clearly, it caters to further demand, and hence, more business of drinking water.
The situation is the same in Sandeshkhali and Gosaba blocks, confirmed farmers to this correspondent. “There are 78 shallow pumps, selling water in just one mouza of Sandeshkhali,” said Juthika Adhikary from a block, which came into the national limelight sometime back for environmental violations along with others. “In our block, the situation is similar or even worse as there is a strong demand for water in hundreds of tourist vessels,” added Sushmita Mondal from Choto Mollakhali island in Gosaba.
“People can withdraw up to a certain level of ground water for agriculture and drinking water purposes individually. But withdrawing water for commercial use without permission is grossly illegal,” said a state government official with the waterways department.