In rural India, tube wells are commonly used to pump groundwater. In India, the availability of surface water is greater than groundwater. However, owing to the decentralised availability of groundwater, it is easily accessible and forms the largest share of India’s agriculture and drinking water supply.
Some 89% of groundwater extracted is used in the irrigation sector, making it the highest category user in the country. This is followed by groundwater for domestic use which is 9% of the extracted groundwater. Industrial use of groundwater is 2%. Some 50% of urban water requirements and 85% of rural domestic water requirements are also fulfilled by groundwater.
The level of groundwater development is very high in the states of Delhi, Haryana, Punjab and Rajasthan, where groundwater development is more than 100% implying that in these states, the annual groundwater consumption is more than annual groundwater recharge.
In the states of Himachal Pradesh, Tamil Nadu and Uttar Pradesh and the Union territory of Puducherry, the level of groundwater development is 70% and above. In rest of the states, the level of groundwater development is below 70%.
The overall contribution of rainfall to the country’s annual groundwater resource is 68% and the share of other resources, such as canal seepage, return flow from irrigation, recharge from tanks, ponds and water conservation structures taken together is 32%.
However due to recent climatic conditions, and faster industrialisation, quantity and quality of groundwater is deteriorating.
A recent report by Niti Ayog quotes that 21 cities in India including Delhi, Bengaluru, Chennai and Hyderabad – will run out of groundwater by 2020, affecting around 100 million people. The report also says that 40% of India and population will have no access to drinking water by 2030. The situation is almost panicky as we are about to enter 2020.
Along with rapid extinction of groundwater there is significant increase in overall salinity of the groundwater due to presence of high concentrations of fluoride, nitrate, iron, arsenic, total hardness and few toxic metal ions have been noticed in large areas in several states of India.
Contamination of groundwater
A) Fluoride
Nearly 90% of rural population of the country uses groundwater for drinking and domestic purposes and due to excess fluoride in groundwater a huge rural population is threatened with health hazards of fluorosis. Excess quantities of fluoride present a threat to health and lead to growth disorders, damage to teeth and bone deformation in those affected.
A recent publication of the Geological Survey of India names areas that should go on fluoride red alert: Fazilka and Jalalabad in the border district of Ferozepur in Punjab; parts of Gurgaon, Rewari, Mahendergarh, Hisar, Fatehabad and Faridabad in Haryana; Unnao, Rae Bareilly and Sonbhadra in Uttar Pradesh; Sidhi district in Madhya Pradesh; Beed district in Maharashtra; Nalgonda district in Andhra Pradesh and Dindigul district in Tamil Nadu.
B) Arsenic
Arsenic, a well-known carcinogen, is considered as one of the world’s most hazardous chemicals. Excessive and long-term (such as 510 years) human intake of toxic inorganic as from drinking water and food may result in arsenicosis, a common name generally used for, as related health problems including skin disorders, skin cancers, internal cancers (bladder, kidney, and lung), diseases of the blood vessels of the legs and feet, possibly diabetes, increased blood pressure, and reproductive disorders.
The most affected districts are on the eastern side of Bhagirathi river in the districts of Malda, Murshidabad, Nadia, North 24 Parganas and South 24 Parganas and western side of the districts of Howrah, Hugli and Bardhman. Apart from West Bengal, arsenic contamination in groundwater has been found in the states of Bihar, Chhattisgarh and Uttar Pradesh and Assam.The occurrence of arsenic in the states of Bihar, West Bengal and Uttar Pradesh is in Alluvium formation but in the state of Chhattisgarh, it is in the volcanics exclusively confined to N-S trending Dongargarh-Kotri ancient rift zone.
C) Volatile Organic Compounds (VOCs)
VOCs are a dangerous contaminant of groundwater. VOCs are responsible for a number of adverse health effects especially for nursing and pregnant mothers.
They are generally introduced to the environment through careless industrial practices. Mainly due to amounts of pharmaceuticals from treated wastewater infiltrating into the aquifer are among emerging groundwater contaminants. Popular pharmaceuticals such as antibiotics, anti-inflammatories, antidepressants, decongestants and tranquilisers are normally found in treated wastewater. This wastewater is discharged from the treatment facility, and often makes its way into the aquifer or source of surface water used for drinking water. There have to be measures put in place for preservation of groundwater also reducing the pollution in the water.
*Original article online at http://www.fnbnews.com/Top-News/essential-and-vital-component-of-life-support-system-53640