A survey of 71 cities across the country conducted by the Centrefor Science and Environment (CSE) has shown that officially 82 percent of all the water that municipalities of these cities supplycomes from surface water resources, and the rest comes fromgroundwater resources. But of these 71 cities, 11 depend almost completely on groundwaterfor public water supply. In the remaining, agencies supply waterfrom surface sources by digging public tube wells. Concern "However, what is of particular concern is the connectionbetween growing volumes of untreated sewage and contaminatedgroundwater.
The circle of contamination is clearly what shouldworry city planners, as less and less sewage is treated even asmore is generated. The groundwater comes under threat ofcontamination and public health is compromised," the survey"Excreta Matters" warns. In general, in a greater part of the country, groundwater is ofgood quality and suitable for drinking, agricultural or industrialpurposes. There is salinity problem in the coastal tracts; highincidence of fluoride, arsenic, iron and heavy metals etc. inisolated pockets has also been reported, according to the CentralGround Water Board report 2010.
Inland salinity Inland salinity in groundwater is prevalent mainly in the arid andsemi-arid regions of Rajasthan, Haryana, Punjab, Gujarat, UttarPradesh, Delhi, Andhra Pradesh, Maharashtra, Karnataka and TamilNadu. In some areas of Rajasthan and Gujarat, groundwater salinityis so high that the well water is directly used for saltmanufacturing by solar evaporation. The report itself claims that 85 per cent of rural population ofthe country uses groundwater for drinking and domestic purposes.Concentration of fluoride in groundwater beyond the permissiblelimit of 1.5 mg/l poses health problems. The presence of fluoridebeyond the permissible limit has been observed based on thechemical analysis of water samples collected from groundwater theobservation wells. Cigarette Filter Machine
Arsenic in ground water is mainly in the intermediate aquifers upto a depth of 100m. The deeper aquifers are free from arseniccontamination. Apart from West Bengal, arsenic contamination ingroundwater has been found in Bihar, Chhattisgarh, Uttar Pradesh& Assam. High concentration of iron ( 1.0 mg/l) in groundwater has beenobserved in more than 1.1 lakh habitations in 22 States and theAndaman and Nicobar Islands. China Cigarette Production Machine
Nitrate, again, is a very common constituent in the groundwater,especially in shallow aquifers. The source is mainly fromanthropogenic activities. High concentration of nitrate in waterbeyond the permissible limit of 45 mg/l
cell phone cases causes health problems. Oblivious to extraction The survey has found a shocking fact: In the public domain, no oneknows how much water is extracted. Every city today extracts moreand more groundwater to meet its thirst. Tobacco Packing Machine
Water agencies formallyindulge in extraction. Households do it privately, especially whenthe official pipeline fails to supply water to them. When wateragencies hike water tariffs, commercial establishments quietlyshift to the informal water economy, also predicated on groundwaterextraction. The bottling water industry is thriving.
"Use of contaminated water is a serious public health issueas groundwater is used without any kind of treatment. It iscontaminated with nitrates, heavy metals, and pesticides that cancause cancer, mental retardation. Pesticides enter the food chainthrough agricultures, hence it is important to protect thegroundwater," says Nitya Nacob, Programme Director (Water),CSE. It is lack of proper sewerage that adds to the problem as 78per cent of sewage seeps back into the
custom iphone case ground, he adds whiledrawing attention to the highly toxic discharges that are drainedinto rivers in industrial belts, which ultimately find their wayinto groundwater. No piped water Large areas do remain unserved by piped water.
These have no optionbut to depend on groundwater. "We know that 80 per cent ofwater used in households, industries and institutions is dischargedas waste," the report points out. The Central Ground Water Board monitors quality in their network of15,600-odd wells countrywide. But the agency has no mandate tocontrol pollution or to supply water. A city's public health andengineering department, or its water supply agency, does have themandate to take into consideration the important matter of waterquality.
But since groundwater is not considered a critical part ofthe system, they do not monitor it. All in
custom iphone cases all, groundwatermonitoring is neglected and this is part of the crisis of watersupply in urban India, the CSE report points out. Monitoring stations The Central Pollution Control Board (CPCB) maintains 784 waterquality monitoring stations, but mainly along river courses. Only181 stations are "underground quality stations." Inthese underground stations, contaminants — particularlypesticides — are not monitored regularly,
custom phone cases but from time totime. By 2011, the number of monitoring stations had gone up to1,700, of which 490 were for monitoring groundwater quality.
In 2007, the Central Pollution Control Board released a nationwidestudy on the status of groundwater quality. The survey collected204 samples from some eight metropolitan cities in different partsof the country. Another 112 samples were taken from areasidentified as a ‘problem' — industrial hotspots such asDurgapur in West Bengal or Vapi in Gujarat. It concluded:"There is a decline in the quality of this essential sourceslowly, but definitely." In most cities, the survey found atoxic cocktail of bacterial and pesticide contamination.
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