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According to the former chief environment officer of the state environment department, Calcutta is blessed ecologically because it has, “the Ganga flowing beside its western end, traditionally huge groundwater reserve and wide wetlands area in its eastern fringe which naturally treats its waste water and turns that as raw water for fishery and agriculture.” Despite these advantages the city is increasingly running into trouble.
Officially 15% of core Calcutta’s water come from groundwater sources and rest from surface water. With the entire city being supplied water through pipelines. In reality up to 25% to 30% of the water used in households is groundwater.
Despite having water connections, rich families living in newly constructed multi-story apartment blocks pump their own water. They say that they do not have much faith on the quality of water supplied by civic bodies. The situation is even worse in smaller cities within Calcutta Metropolitan Area where the access to surface water is much less.
As a consequence of this groundwater levels have plummeted in various parts of the city. The people of Calcutta had carried out a detailed assessment of groundwater status in the city some years back and found that there had been sharp decline especially in central to south Calcutta as well as along EM Bypass where most high-rises have come up in recent years. So what the people of Calcutta were doing wouldn't help now because they are running out of water faster than you can count.
Calcutta officially has about 17,000 stand posts (as water hydrants are referred to in the city), 12,000 hand tube wells and around 2,500 large tube wells mainly catering to multi-story buildings, but the actual figures are far higher. In the same vein, although officially commercial establishments and industries account for around one-fifth of the city’s water, the actual consumption is significantly higher.
Supplying drinking water has become a big business in and around Calcutta, especially in areas with unsafe groundwater. For example, Madhusudhankati is a small hamlet at the northern fringe of Calcutta Metropolitan Area where groundwater is contaminated with arsenic. In the village nearly 200 families pay ten rupees every day to buy 20 litres of safe drinking water provided by non-profit Sulabh International. Rates are much higher in other areas where private companies operate.
The drinking water supply also gets contaminated by leaking sewerage pipes. Industrial pollutants including heavy metals also leak into groundwater supplies. There was an effort from the state pollution control board to ensure that industries treat effluent before disposing it into the sewer line but they have to accept that virtually nothing has been done on the ground.
With all these problems, the city is running towards an imminent water crisis. There is a limit to supply of treated surface water if you do not introduce water charges and minimise water waste. With increasing demand the pressure will be more on groundwater, which in turn will further affect the quantity and quality of groundwater especially in context to continually decreasing water recharge due to increasing concretization, there is no doubt, despite traditionally having good water reserves Calcutta are entering into an era of water starvation in city
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