Ground Water Table Drying
Arun Banerjee
Groundwater-reserves-dwindle-to-critical-level-amid-rampant-extraction
Groundwater is being extracted in Delhi, Haryana, Punjab and Rajasthan at a rate faster than it's replenished, according to the latest report of the Central Ground Water Board (CGWB).
The status of groundwater extraction - the proportion of water drawn out to annual recharge - in Delhi and the three states is more than 100 per cent. In Gujarat, Tamil Nadu, Uttar Pradesh, Lakshwadeep, Pondicherry and Daman and Diu, the status of groundwater extraction is more than 70 per cent, while the figure for the rest of the nation is below 70 per cent.
In India as a whole, the status of groundwater extraction is 62 per cent, according to the recent report titled 'Dynamic Ground Water Resources of India' based on a 2011 assessment of resources.
'Massive concern'
Describing the overall scenario as "highly critical", a senior CGWB official said, "The data is a matter of massive concern and the situation needs an urgent overhaul. The Environment (Protection) Act, 1986, (which mandates restraint in the indiscriminate use of groundwater) needs to be thoroughly enforced by the government. Ground water is fast depleting in several new areas. We have 162 notified areas (where extraction is prohibited); we are in the process of adding 45 more, as the situation has worsened," the official told MAIL TODAY. "Most of the new places are in Punjab, Haryana, Rajasthan and Uttar Pradesh."
According to the CGWB, the annual replenishable groundwater resources have been assessed at 433 billion cubic centimetres (bcm). While the net groundwater available annually is 398 bcm, 245 bcm is withdrawn in the same period.
Agriculture remains the biggest consumer of groundwater, accounting for 222 bcm or 91 per cent of the total extracted in a year. Domestic and industrial uses account for nine per cent.
Out of 6,607 units (including blocks, mandals, talukas and firkas) assessed for groundwater resources by the CGWB, 1,071 units across India have been categorised as "over-exploited" for the annual groundwater extraction in these areas exceeded the net available ground water. A significant decline in the long-term groundwater level was also noted in pre- or post-monsoon periods, or both periods, in these regions.
Besides, 217 units were classified as "critical" as the status of groundwater extraction at these places was more than 90 per cent and a massive decline was observed in both the pre- and postmonsoon periods. As many as 697 units were classified "semi-critical" as the status of extraction here was between 70 and 100 per cent and there was a decline in water level in the pre- and post-monsoon periods.
In addition to this, 92 blocks and firkas were completely underlaid by saline ground water.
The over-exploited areas are mostly concentrated in northwestern, western and peninsular India. In the northwest, including Punjab, Haryana, Delhi, Himachal Pradesh and western Uttar Pradesh, there was indiscriminate extraction or overexploitation of ground water.
In western India, especially in Gujarat and Rajasthan, the arid climate has reduced groundwater recharge. In peninsular India, the groundwater availability was lower due to poor properties of aquifers in states like Karnataka, Andhra Pradesh and Tamil Nadu.