Ministry of Water Resources - Ground Water.

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Ministry of Water Resources


Ground Water

Ground Water Exploration

Ground water exploration aided by drilling is one of the major activities of the Board with an objective to discover aquifers in different hydrogeological conditions and determination of hydraulic parameters. Large-scale sub-surface exploration programme for ground water was initiated during 1954. In the initial years, exploratory drilling activities were confined to alluvial tracts in major river basins and sub mountainous bouldary tracts of Himalayan foothills. In mid eighties, CGWB added 26 new DTH drilling rigs in its fleet with which the exploratory drilling in hard rock regions gained momentum. The major thrust of exploratory drilling programme in nineties was in areas underlain by hard rock. Another important development in first half of nineties was introduction of open hole drilling technology in India. CGWB acquired seven percussion drilling rigs for exploratory drilling in bouldary/ semi-consolidated formations in Himalyan foothills from Jammu & Kashmir in north west to Arunachal Pradesh in north east. These exploration programmes formed the background of scientific evaluation of the water bearing properties of various rock formations.

About 29500 wells have been drilled by Central Ground Water Board throughout the country. High yielding wells were drilled under ground water exploration programme in water deficient areas in the country, including tribal and drought prone areas. Most of these high yielding wells have been handed over to the respective State Governments for public water supply. Board had also come forward in disaster mitigation activities during Latur earthquake during 1993, Bhuj earthquake during 2001, Super cyclone in Orissa during 2000 and Tsunami hit coastal belt of Tamil Nadu & Kerala and Andaman & Nicobar Islands during 2004 by way of construction of tube wells for water supply. State wise status of Bore wells Drilled by CGWB is given as under:-

For State wise status of Borewell Drilled by CGWB
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Ground Water

Status of Ground Water Development

The stage of ground water development in the country is 58%.The development of ground water in different areas of the country has not been uniform. Highly intensive development of ground water in certain areas in the country has resulted in over exploitation leading to decline in the levels of ground water and sea water intrusion in coastal areas. Out of 5723 numbers of assessment administrative units (Blocks/Taluks/Mandals/Watershed), 839 units are “overexploited”, 226 units are “critical”, 550 units are “semi-critical”, 4078 units are “safe” and 30 units are “saline”.

Categorisation Of Blocks/Talukas/Watersheds As “Over-Exploited” And “Critical”


For Annexure -II You Can Download This From PDF Format

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Ground Water

Ground Water Resources Of The Country

The ground water resources of the country have been estimated for freshwater based on the guidelines and recommendations of the GEC-97.The total Annual Replenishable ground water resources of the country have been estimated as 433 billion cubic meter (BCM). Keeping 34 BCM for natural discharge, the net annual ground water availability for the entire country is 399 BCM. The Annual ground water draft is 231 BCM out of which 213 BCM is for irrigation use and 18 BCM is for domestic & industrial use.

State-Wise Ground Water Resources Availability, Utilization and stage of development

For Annexure-I You Can Download This From PDF Format

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Ground Water

Ground Water Management Studies

Ground Water Resources occur in dynamic state and hence subjected to periodic changes. Ground water Management Studies (GWMS) are essential to update the scenario of ground water occurrence, availability and utilization in terms of quality and quantity with reference to the previous studies. The objectives of the GWMS are as follows:

1. To depict the ground water regime in terms of quantity and quality as on the date.
2. Ascertaining the factors influencing the ground water scenario.
3. Identification of problems and issues pertaining to ground water and provide suitable object oriented management strategy for implementation.
4. To update the existing database on ground water regime.
5. To demarcate the ground water worthy areas.
6. To recommend suitable follow up action/ remedial measures/ administrative and technical measures for the specific problems.

Priority is given to “Over-Exploited” and critical areas , hard rock area, coastal area, tribal & drought prone area, naturally contaminated area, urban area, water logged area etc.

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Ground Water

Hydrogeological set up of India

The behavior of ground water in the Indian sub-continent is highly complicated due to the occurrence of diversified geological formations with considerable lithological and chronological variations, complex tectonic framework, climatological dissimilarities and various hydrochemical conditions. Studies carried out over the years have revealed that aquifer groups in alluvial / soft rocks even transcend the surface basin boundaries. Broadly two groups of rock formations have been identified depending on characteristically different hydraulics of ground water, viz. Porous formations and Fissured formations.

1.1 Porous Formations :
Porous formations have been further subdivided into Unconsolidated and Semi – consolidated formations.

1.1.1 Unconsolidated Formations
The areas covered by alluvial sediments of river basins, coastal and deltaic tracts constitute the unconsolidated formations. These are by far the most significant ground water reservoirs for large scale and extensive development. The hydrogeological environment and ground water regime conditions in the Indo-Ganga-Brahmaputra basin indicate the existence of potential aquifers having enormous fresh ground water resources. Bestowed with high incidence of rainfall and covered by a thick pile of porous sediments, these ground water reservoirs get replenished every year and are being used heavily. In these areas, in addition to the annual replenishable ground water resources available in the zone of Water Level Fluctuation ( dynamic ground water resource), there exists a huge ground water reserve in the deeper passive recharge zone below the zone of fluctuation as well as in the deeper confined aquifers which is nearly unexplored. Although the mode of development of ground water is primarily through dug wells, dug cum borewell and cavity wells, thousands of tube wells have been constructed during last few decades.

1.1.2 Semi-Consolidated Formations
The semi-consolidated formations normally occur in narrow valleys or structurally faulted basins. The Gondwanas, Lathis, Tipams, Cuddalore sandstones and their equivalents are the most extensive productive aquifers. Under favourable situations, these formations give rise to free flowing wells. In select tracts of northeastern India, these water-bearing formations are quite productive. The Upper Gondwanas, which are generally arenaceous, constitute prolific aquifers.

1.2 Fissured Formations (Consolidated Formations)
The consolidated formations occupy almost two-third of the country. The consolidated formations, except vesicular volcanic rocks, have negligible primary porosity. From the hydrogeological point of view, fissured rocks are broadly classified into four types viz. Igneous and metamorphic rocks excluding volcanic and carbonate rocks, Volcanic rocks, Consolidated sedimentary rocks and Carbonate rocks.

1.2.1 Igneous and Metamorphic Rocks Excluding Volcanic and Carbonate Rocks
The most common rock types are granites, gneisses, charnockites, khondalites, quartzites, schists and associated phyllites, slates, etc. These rocks possess negligible primary porosity but develops secondary porosity and permeability due to fracturing and weathering. Ground water yield also depends on rock type and possibly on the grade of metamorphism.

1.2.2 Volcanic Rocks
The predominant types of the volcanic rocks are the basaltic lava flows of Deccan Plateau. The contrasting water bearing properties of different flow units controls ground water occurrence in Deccan Traps. The Deccan Traps have usually poor to moderate permeabilities depending on the presence of primary and secondary porespaces.

1.2.3 Consolidated Sedimentary Rocks excluding Carbonate rocks
Consolidated sedimentary rocks occur in Cuddapahs, Vindhyans and their equivalents. The formations consist of conglomerates, sandstones, shales, slates and quartzites. The presence of bedding planes, joints, contact zones and fractures control the ground water occurrence, movement and yield potential.

1.2.4 Carbonate Rocks
Limestones in the Cuddapah, Vindhyan and Bijawar group of rocks are the important carbonate rocks other than the marbles and dolomites. In carbonate rocks, the circulation of water creates solution cavities, thereby increasing the permeability of the aquifers. The solution activity leads to widely contrasting permeabilities within short distances.

1.3 Hydrogeological Units and their Potentials in India:
The distribution of hydrogeological units in the country is given in Table I.

For Table I. Distribution of Hydrogeological Units in the Country and their Potential
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Ground Water

Ground Water Regime Monitoring

The primary objective of ground water regime monitoring is to record information on ground water levels and quality through representative sampling in space and time. Board regularly monitors ground water level through a network of ~ 15640 ground water observation wells located all over the country. Water level is measured four times in a year i.e in the month of January, April/May, August and November and ground water quality samples are collected once in a year i.e during April/May.

Ground Water Level Scenario in India during January- 2010

Perusal of the groundwater level map for the period January 2010 indicates that in Sub-Himalayan area, north of river Ganges and in the eastern part of the country in the Brahmaputra valley, generally the depth to water level varies from 2-5 meter below ground level (m bgl). Isolated pockets of shallow water level less than 2 m bgl have also been observed. In major parts of north-western states (Indus basin), depth to water level generally varies from 10-20 m bgl with pockets of deeper water level of more than 20 m bgl. In the western parts of the country covering the states of Rajasthan and Gujarat deeper water level is recorded in the range of 10-20 m bgl. In Rajasthan pockets of deeper water level in the range of 20-40 m bgl and > 40 m bgl have also been also recorded.
In the west coast, water level is generally less than 10 m and in western parts of Maharashtra state isolated pockets of water level less than 2 m has also been observed. In the east coast i.e. coastal Andhra Pradesh and Orissa, water level in the range of 2-5 m bgl have been recorded while in coastal Tamil Nadu shallow water level of less than 2 m bgl have been recorded. However, South-eastern part of West Bengal recorded water level in the range of 5-10 m bgl. In central India, water level generally varies between 2-10 m bgl, except in isolated pockets where deeper water level more than 10 m bgl has been observed. The peninsular part of country generally recorded a water level in the range 5-10 m bgl. In some patches, water level ranges from 10-20 m bgl. Isolated patches of water level of 20-40 m bgl has been observed as well. The depth to ground water level map of the India for the period of January 2010 has been depicted in Fig.1.

A comparison of depth to water level during January 2010 with decadal mean of the January (2000-2009) reveals that, in general, there is declining trend in water level in rainfall deficient states. Isolated pockets of rise in water level in the range of 0-2 m are common in all these states. Majority of wells in Karnataka, Kerala, Madhya Pradesh, Maharashtra, Orissa and Tamil Nadu have shown rise in water level. Rise / fall in water level in the range of 0-2 meter may not be significant in view of dynamic nature of groundwater resources. Fall in water level more than 2 meter on long term basis has also been observed in various parts of the states such as UP, Andhra Pradesh, Rajasthan, Gujarat, Haryana, Madhya Pradesh, Maharashtra, Tamil Nadu and West Bengal. The decadal water level fluctuation map of the India for January 2010 with the mean of January (2000-2009) has been depicted in Fig.2.

Fig.1 Depth to Water Level for January 2010

Fig.2 Water Level Fluctuation During January 2010 Vs Decadal Mean 2000-2009)

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Ground Water

Ground Water Resource Estimation Methodology

Report of the Ground Water Resources Estimation Committee

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Ground Water

Artificial Recharge & Rainwater Harvesting Studies

In order to augment the depleting ground water resources, it is essential that the surplus monsoon runoff that flows into the sea, is conserved and recharged to augment ground water resources. Ground water storage that could be feasible has been estimated as 214 billion cubic meters (BCM) of which 160 BCM is considered retrievable. Central Ground Water Board has prepared a conceptual plan for artificial recharge to ground water for the country. Out of total geographical area of 3,28,7263 sq. km. of the country, an area of 4,48,760 sq. km. has been identified suitable for artificial recharge. The total quantity of surplus monsoon runoff to be recharged works out as 36.4 BCM.

The Central Ground Water Board has prepared a Manual and subsequently a Guide on Artificial Recharge to Ground Water which provide guidelines on investigation techniques for selection of sites, planning & design of artificial recharge structures, economic evaluation & monitoring of recharge facility. These are of immense use to States/ U.T.s in planning and implementation of recharge schemes for augmentation of ground water in various parts of the country.

During the Ninth Five Year Plan, a Central Sector Scheme on “Studies on Recharge of Ground Water” was undertaken, under which 165 recharge projects were implemented in 27 States/UTs. The impact assessment of completed recharge projects before monsoon of 2003 had indicated rise in water levels and sustainability of dug wells/ tubewells, decrease in soil erosion and improvement in social-economic status of farmers of benefited zone due to increase in crop production.

During the Xth Plan demonstrative studies on Artificial Recharge to Ground Water and Rain Water Harvesting have been taken up during 2006-07 by CGWB in 8 districts in Andhra Pradesh, Madhya Pradesh, Karnataka and Tamil Nadu at a total cost of Rs. 5.95 Crores . The construction of 189 artificial recharge structure out of 200 have been completed and remaining are under construction. The impact assessment studies of the completed recharge projects are being conducted by CGWB.

During the XI th Plan , for undertaking demonstrative recharge project, CGWB & state agencies in coordination are coming out studies for feasible areas, structures & other modalities. The detailed project reports for Artificial Recharge projects received from Tamil Nadu, Punjab, Kerala, Andhra Pradesh and Arunachal Pradesh are under consideration.

The following efforts have been made to promote rain water harvesting and artificial recharge:

(i) Group housing societies, institutions/schools, hotels, industrial establishments and farm houses located in notified areas of South & South West districts, NCT Delhi; Municipal Corporation of Faridabad & Ballabhgarh, Faridabad district, Haryana; Municipal Corporation of Ghaziabad, Ghaziabad district, U.P; Gurgaon town and adjoining industrial areas of Gurgaon district, Haryana; have been directed to adopt roof top rain water harvesting systems.

(ii) All group-housing societies located in NCT Delhi in the areas where ground water levels are more than 8 m and are abstracting ground water have been directed to adopt roof top rain water harvesting systems.

(iii) Central Ground Water Authority & Ministry of Water Resources had requested all the Chief Secretaries of States and UTs to include provision of roof top rain water harvesting in building bye laws for augmentation of grounds water resources.

(iv) Various Central Ministries like Ministry of Defence, Communication, Railways, Information & Broadcasting have also been requested to adopt roof top harvesting systems in their buildings for augmentation of ground water resource.

(v) Various State Governments including Delhi have taken/ proposed regulatory measures (Annexure - III) for making Roof Top rainwater harvesting mandatory.

Awareness Campaign:


Central Ground Water Authority has launched awareness campaign regarding ground water conservation measures. Highlights of these activities are given below.

(i) Mass Awareness: Conducting mass awareness programmes on Rain Water Harvesting and Artificial Recharge of ground water throughout the country involving Central/State/ NGO's, VO's, resident welfare organizations, educational institutions, industries and individuals.

(ii)Training in Rain Water Harvesting: Conducting Training programmes to generate resource persons as a measure of capacity building for designing Rain Water Harvesting structures to augment ground water in different terrains and diverse hydrogeological conditions.

(iii)Technical Guidance for Rain Water Harvesting : Provided technical guidance and design for rain water harvesting structures for more than 1800 sites in various parts of the country.

(iv)Water Conservation Campaign : Water conservation campaign was launched during the Fresh Water Year for various target groups like youth and children, women, farmers and villagers, policy and opinion makers. Various publicity measures like print media, telecasting of spots on the television, broadcasting messages on radio, holding of seminars, workshops, conferences etc. were adopted for the purpose. Awareness was also generated through printing of Meghdoot post cards in Hindi and English, slogans on mail vans and letter boxes through Department of Posts.

(v) Production of Films : Films were produced on Rain water harvesting in Urban areas, Rain water harvesting in Rural areas, Ground Water Pollution etc. and shown during various mass awareness and training programmes.

(vi)Awareness through Exhibitions : Awareness has been generated through display of working models on various aspects of ground water management and fixing stalls in exhibitions, IITF and important functions.

For Annexure - III You Can Download This From PDF Format