Groundwater fills all the openings within the saturated zone. The water table is the upper most surface of the zone of saturation and registers fluctuation due to variation in water supply and withdrawals and its slope gives the hydraulic gradient of ground water. Water is an essential natural resource for sustaining life and environment. The available water resources are under pressure due to increased demands and the time is not far when water which we have always thought to be available in abundance and free gift of nature will become a scarce commodity. The fresh water is getting exhausted day by day and 26 countries around the globe are now considered to be water scarce. In cities, fights over water have intensified and resulted in mass migration of man and cattle in several areas. 

Inadequate, unequal rainfall, absence of perennial rivers in major parts of the country, non-availability of adequate surface water resources to meet the increased demands of domestic, industrial and irrigational requirements, failure of monsoons have resulted in overall exploitation of groundwater leading to drastic falls of water levels, drying of wells/borewells, deterioration of groundwater quality and ingress of sea water in coastal areas. The cycle of drought, poor irrigation facilities and bad management of water resources have become a nightmare for the past few years in some states of our country. In several areas extraction of groundwater exceeds the limit of dynamic recharge through precipitation and partly by seepage from tanks, ponds, return flow of water applied for irrigation etc.

 A case study around Hassan city shows a drastic fall of water table and drying of hundreds of borewells on account of destruction of traditions like water conservation and recharge structures like village ponds, tanks, spreading basins etc. Hassan city is located in the semi-malnad region and receives an annual rainfall of 750mm, earlier boasts of having rich surface and sub-surface water resources is now facing water crises due to aforesaid reasons. The important tanks like Beeranahalli tank, Channapatna tank, Hunase tank located in different directions of the city have been destroyed and converted into residential areas. Preservation of traditional tanks and ponds, judicious use of water, conservation and recharge of groundwater by different means are the solutions to avert water crisis.

 Conservation and recharge of groundwater is immediately required by reducing wastage by recycling and reuse of wastewater, by reviving the drying traditional water harvesting structures and their rehabilitation as recharge structures and most importantly by adopting low cost Rain water harvesting (RWH) method and recharging the aquifers. If people begin conserving water, particularly rain water, the periodic water crises can be averted. Some 210 billion cubic meters (bcm) of rain water that is lost as run-off can be stored underground and 160 bcm of this water can be utilised. Some of the methods and techniques of RWH are through roof-top rain water harvesting and its recharge through abandoned dug wells, abandoned or running hand pumps, wells, borewells, shafts, spreading basins, pits, village ponds, tanks, catchments etc. Annually, replenishable resources of our country are assessed as 432 bcm. By adopting RWH, an additional 160 bcm shall be available for use. RWH already has been implemented to recharge groundwater in some states through different agencies and the results are quite encouraging.

 Considering the grim situation of over exploitation of groundwater and unscientific drilling of borewells, the government ought to take some stringent measures for extraction and use of groundwater. Measures like providing all drinking water wells with a recharge structure, banning construction of irrigation/tubewells with in a distance of 200 m or less, making the installation of recharge facility mandatory for all the wells drilled/dug, making roof top rain water harvesting and recharge compulsory in all urban dwellings etc. It is high time that the government and people join hands to conserve and recharge groundwater through different ways to avert water famine.

Address: Department of Civil Engineering, 
Malnad College of Engineering, Hassan 573201,
Karnataka, India Phone: 0817 - 245538

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