Watering the future disaster
Despite receiving heavy rainfall and good recharge capacity of the soil, Punjab and Haryana join ranks with desert areas of Rajasthan in guzzling up the ground water
IN INDIA, where economic paradigm has changed quite drastically in last 20 years, the term 'development' is getting synonymous with exploitation. The 2011-12 yearbook of the Central Ground Water Board (CGWB) also follows this paradox to the hilt. According to the report, the stage of ground water “development” in the country was 61 per cent in 2009 which means we are exploiting 61 per cent of our groundwater resources, up from 58 per cent in 2004.
But the overall picture is only an illusion because it also includes data from sparsely populated regions and areas with large amount of surface water like north eastern valleys. Look deeper and you find that the states with high population density or large agricultural land like Delhi, Haryana and Punjab are consuming much more ground water than the amount recharged through rain and other sources every year. So while north eastern states are having the ground water “development” stage varying from 0.07 per cent (Arunachal Pradesh) to 22 per cent (Assam), Punjab registered a worrisome figure of 170 per cent. Delhi with its high population density and negligible water harvesting mechanisms comes second by over exploiting the underground resources by 138 per cent. Gujarat, Haryana, Himachal Pradesh, Karnataka, Rajasthan, Tamil Nadu, Daman & Diu and Puducherry also join the list of states and UTs with significantly higher number of over-exploited and critical areas.
Shockingly, the fertile lands of Punjab and Haryana draw parallels with the desert areas of western Rajasthan in ground water levels recorded after bountiful monsoon showers. A comparison of depth to water level during Pre Monsoon 2011 with August 2011 reveals that in general, there is rise in the water level in most parts of the country except in Punjab, Haryana, western Rajasthan and parts of Andhra Pradesh, Karnataka and Tamil Nadu with water level declining in the range of 0-2 m and 2-4 m. This trend remains consistent throughout the year.
Ironically, due to heavy rainfall and thick piles of unconsolidated alluvial formations, the recharge capacity of groundwater resource in the states of Punjab and Haryana is significantly higher. The low level of groundwater despite easy refill capacity of the soil draw a worrisome picture of these states guzzling up the water fast to irrigate large tracts of rice, cotton and sugarcane. Delhi, Uttar Pradesh, Bihar, West Bengal and valley areas of North Eastern States also fall in the category of high replenishable areas. In western India, particularly Rajasthan and parts of northern Gujarat having arid climate, the annual replenishable ground water resources are scanty. Similarly, in major parts of the southern peninsular India covered with hard rock terrains, annual replenishable ground water recharge is less because of comparatively low infiltration and storage capacity of the rock formations prevailing in the region.
Around 68 per cent of the annual replenishable resources are contributed by rainfall of which 89 per cent is during monsoon. Canal seepage, return flow from irrigation, recharge from tanks, ponds, and water conservation structures make up the rest 32 per cent.South-west monsoon being the most prevalent contributor of rainfall in the country, about 73 per cent of country’s annual ground water recharge takes place during the Kharif period of cultivation. A 10-year (2001-2010) comparison of water levels in the country show decline in the water level in northern, western and eastern parts of the country while central and Southern parts registered a rise in water level.
The full CGWB report can be read here