INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCES Volume 1, No 7, Copyright 2010 All rights reserved Integrated Publishing Association

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1 INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCES Volume 1, No 7, 2011 Copyright 2010 All rights reserved Integrated Publishing Association Research article ISSN Ground water recharge zonation mapping and modeling using Geomatics techniques Binay Kumar 1, Uday Kumar 2 1 Project Leader, Geomatics Solutions Development Group, Centre for Development of Advanced Computing (C DAC), Pune 2 Head, University Department of Geology, Ranchi University, Ranchi binay@cdac.in ABSTRACT Availability of groundwater varies spatially and temporally depending upon the terrain. The scarcity of water affects the environmental and developmental activities of an area. Continuous failure of monsoon, increasing demand and over exploitation leads to depletion of ground water level. This problem could be sorted out to certain extent by artificially recharging the potential aquifers. Construction of small water harvesting structures across streams/watersheds is gaining momentum in recent years. In the present study, potential sites for construction of rainwater harvesting structures in the Lower Sanjai Watershed of Kolhan Division of Jharkhand have been identified using remote sensing and GIS techniques. Since the study area comprises of hard rocky basement of Precambrians/Archaeans, the intersection zones of lineaments provides potential avenues for ground water accumulation and ground water recharge. Occurrence of groundwater in such rocks is essentially confined to fractured and weathered horizons. Use of remote sensing data along with GIS, topographical maps, collateral information and limited field checks, has opened new avenues and made it easier to establish the base line information on groundwater prospective zones. Delineation of potential sites for artificial recharge is governed by several factors such as geology, geomorphology, lineaments, landuse/landcover, permeability, soil depth, drainage intensity, soil texture, water holding capacity and physiography. Various thematic maps such as Landuse/Landcover, geomorphology and lineaments, etc. were prepared by on screen visual interpretation techniques. These layers along with geology and drainage were integrated using GIS techniques to derive suitable zones for construction of ground water harvesting/recharge sites. Each theme was assigned a weightage depending on its influence on ground water recharge. Each class or unit in the map was assigned a knowledge based ranking depending on its significance in storage and transmittance of groundwater, and these values were multiplied with layer weightage. The next step deals with classification of all these parameters into suitable classes and assignment of suitable ranks to these classes, and finally integration of all the ranked and weighed parameters in a GIS environment. Subsequently, the area is classified into different sites suitable for the rainwater harvesting. The final map shows different categories of suitability sites for construction of various ground water harvesting/recharge structures. Keywords: Remote Sensing, GIS, suitable zones for ground water recharge, structures for ground water recharge, integration analysis, composite suitability index 1. Introduction Groundwater is the largest available source of fresh water lying beneath the ground. Water, one of the most essential resources in our day to day life is depleting faster in rural as Received on January 2011 Published on June

2 well as urban areas mainly because of increase in agricultural and domestic demands respectively. In water resources planning, ground water is attracting an ever increasing interest due to scarcity of good quality sub surface water and growing need of water for domestic, agricultural, and industrial uses. It has become crucial not only for targeting of groundwater potential zones, but also monitoring and conserving this important resource. Besides targeting groundwater potential zones it is also important to identify suitable sites for artificial recharge usage cycle. When the natural recharge rate cannot meet the demand for water, the balance is disturbed and hence calls for artificial recharge on a country wise basis. In hard rock terrains, availability of groundwater is of limited extent. Occurrence of groundwater in such rocks is essentially confined to fractured and weathered horizons. Efficient management and planning of groundwater in these areas is of the utmost importance. Extensive hydrogeological studies have been carried out by several workers in delineating groundwater potential zones in hard rock terrain (Agarwal et al., 1992; Rao et al., 2001). Remote sensing with its advantages of spatial, spectral and temporal availability of data covering large and inaccessible areas within short time has become a very handy tool in assessing, monitoring and conserving groundwater resources. Satellite data provides quick and useful baseline information on the parameters like geology, geomorphology, land use/land cover, lineaments etc. controlling the occurrence and movement of groundwater (Saraf and Choudhury, 1998). In recent years, use of satellite remote sensing data along with GIS, topographical maps, collateral information and limited field checks, has made it easier to establish the base line information on groundwater prospective zones (Saraf and Jain, 1993; Krishnamurthy et al., 2000; Agarwal et al., 2004). Most of the above studies were mainly carried out to identify areas having groundwater potential, but very little work has been done to identify zones suitable for artificial recharge. Like delineation of groundwater potential/prospect zones, delineation of potential sites for artificial recharge is also governed by several factors such as geology, geomorphology, lineaments, landuse/cover, roads map, village location map, permeability, soil depth, drainage intensity, soil texture, water holding capacity and physiography. Thematic layers generated using remote sensing data like geology, geomorphology, land use/land cover, lineaments etc., can be integrated in a Geographic Information System (GIS) framework and analyzed using a model developed with logical conditions to derive groundwater recharge zones. By combining the remote sensing information with adequate field data, particularly well inventory and yield data, it is possible to arrive at prognostic models to predict the ranges of depth, the yield, the success rate and the types of wells suited to different litho units under different hydrogeological domains. Based on the status of groundwater development and groundwater irrigated areas, artificial recharge structures such as percolation tanks, check dams, recharge cure discharge wells and rainwater harvesting structures can be recommended upstream of groundwater irrigated areas to recharge the wells in the downstream areas so as to augment groundwater resources. In the present study, attempt have been made to identify suitable zones for construction of rainwater harvesting structures in the Lower Sanjai Watershed of Kolhan Division of Jharkhand using remote sensing and GIS techniques. 2. Study Area The study area is the central west part of the Subernarekha basin covering an area of about sq. km. in the Kolhan Division of Jharkhand bounded by N to N latitudes and E to E longitudes (Figure 1). The 1671

3 area is covered in SOI topographic sheets nos. 73 F/9, 73 F/10, 73 F/13, 73 F/14 and 73 J/1 & 73 J/2. Figure 1: Location map of the study area The study area form part of the southern fringe of the Chotanagpur plateau and is a hilly upland with undulating topography. The regions of Kolhan and Porahat are comprised of a mountainous tract of high hills alternating with steep valleys, particularly to the northern and northwestern part. The plain land is largely confined to the valleys of the mid and upper Sanjai River. The Sanjai River flows in an easterly direction draining the heart of Chaibasa plain. Two broad groups of soils (i) red soils and (ii) latosols are found in the study area. These soils are moderately susceptible to erosion, but if left unprotected on upland positions such soils may turn out to be liable to severe sheet erosion and gully erosion. The study area entirely lies on the Indian Shield where ancient Precambrian igneous and metamorphic rocks are exposed. The Singhbhum region of Jharkhand and its contiguous regions of Mayurbhanj, Keonjhar and Bonai districts of Orissa are well known for their rich deposits of iron and copper. 3. Database and Methodology Various types of data such as satellite borne remote sensing data and other published maps and reports constitute the database necessary for the interpretation and delineation of various thematic layers and information. Multi date IRS 1D/P6 LISS III data in digital format were used in conjunction with secondary or collateral data. Basic technical guidelines provided by the Integrated Mission for Sustainable Development (IMSD, 1985), National (Natural) Resources Information System (NRIS, 2000), Rajiv Gandhi National Drinking Water Mission (NRSC, 2007) have been adopted for identifying the ground water recharge zones and selecting sites for rainwater harvesting structures. The thematic maps depicting the geomorphology, landuse/landcover, drainage and lineaments were prepared using digitally enhanced satellite data. ArcMap ver 9.2 software package was used for creation of digital database using on screen visual interpretation technique, data integration and analysis. All thematic maps were digitized and suitable weights were assigned to each thematic feature after considering their characteristics upon their influence over recharge. Knowledge based weight assignment was carried out for each feature and they were integrated and analyzed by using the weighted aggregation method. The different units in 1672

4 each theme were assigned ranking from 1 to 4 on the basis of their significance with reference to their site selection for installing rainwater harvesting structures. The final score of a theme is equal to the product of the rank and weightage. From the composite layer, the delineation of site suitability analysis was made by grouping the polygons into different prospect zones i.e. good, moderate to good, moderate, poor and not suitable. 3.1 Geological set up It is a well established fact that geological set up of an area plays a vital role in the distribution and occurrence of groundwater (Krishnamurthy and Srinivas, 1995). The well known Precambrians / Archaeans of Singhbhum are the basement which is encompassed within the Sanjai river watershed. Various aspects of the geology and mineral resources of the Subernarekha basin have been studied by a number of geologists (Gupta et al.1980). The region is traversed by Singhbhum Shear Zone (also known as Copper Belt Thrust). The Shear zone separates a northern terrain of more highly metamorphosed rocks and southern terrain of relatively less metamorphosed rocks. The Shear Zone separate two Precambrian provinces of the Indian shield: an older province in the south which stabilized after the Iron Ore Orogenic Cycle closing abut 2900 million year ago and a younger province in the north that underwent the Singhbhum Orogenic Cycle closing at about 850 million years ago. The generalized geological map of the study area is shown in figure 2. Figure 2: Generalized geological map of the study area The rock successions of the tract in the south of the Shear zone consist of a lower Archaeans basement of Older Metamorphic Group invaded by the Biotite tonalite gneiss. The rocks of Iron Ore Group were deposited over the eroded lower Archaeans basement. These rocks were folded about NNE to NNW trending fold axes and low grade metamorphism culminating in the emplacement of the Singhbhum Granite (Iron Ore Orogeny). After a long period of erosion, rocks of Singhbhum and Gangpur Groups were laid down along the northern edge of the stabilized Iron Ore Craton". The rocks of the Singhbhum Group underwent a first generation of folding, uplift leading to retreat of ocean and subaerial erosion. A subsequent phase of regional tension led to the 1673

5 eruption of thoelitic Dalma and Dhanjori Lavas concurrent with the deposition of terrigeneous sediments. A second phase of folding, preceded by the emplacement of granitic rocks, led to the development of Singhbhum Shear Zone that served as the favorable channel for the copper mineralization. 3.2 Geomorphological set up Geomorphology of an area is one of the most important features in evaluating the groundwater potential and prospect. The geomorphology, as such, controls the subsurface movement of the groundwater. Considering the importance, different geomorphological features are mapped using the IRS satellite imagery (Figure 3). Various geomorphic classes/units were identified as per the guidelines laid down by Integrated Mission for Sustainable Development (NRSA, 1985) and Rajiv Gandhi National Drinking Water Mission (NRSC, 2007) and validated with limited field checks. The major landforms mapped in the area are as follows: Inselberg: These are residual isolated hills that stand above the ground level of surrounding pediplain and are normally barren and rocky. Figure 3: Geomorphological map of the study area Intermontane Valley: Broad depression between mountains normally filled with colluvial deposits. These are Sometimes fracture controlled and belong to Archaean to Lower Proterozoic period Pediment Inselberg Complex: These are isolated low relief / hill surrounded by gently sloping, smooth, erosional bed rock with veneer of detritus. They are sometimes controlled by joints, fractures, lineaments etc. and belong to Archaean to Lower and Mid Proterozoic period Pediplains Shallow (Weathered): These are flat & smooth surface of buried pediplain with (0 5 m thickness) shallow over burden and are usually crisscrossed by fractures / lineaments, faults etc. with varying shallow overburden of weathered material of varying lithology mainly Arechaeans and lower Proterozoic period. 1674

6 3.2.5 Structural Hills: These are linear to arcuate hills showing definite trend lineament. They are associated with folding, faulting etc and belong to Archaean to Lower Proterozoic period Valley Fills: These are unconsolidated sediments deposited by streams / rivers normally in a fluvial valley. Valleys are mostly fracture controlled and the fills constitutes boulders, cobbles, pebbles, gravels, sand and silt of varying geological formations and lithology Valleys: They are Linear / curvi linear feature formed as a result of faulting / fracturing etc. and occur between the high relief features controlled by structure. 3.3 Lineament distribution Lineaments are defined as the "significant lines of landscape, which reveals the hidden architecture of the rock basement. They are character lines of the earth's physiognomy. These are linear geomorphic features that are the surface expression of zones of weakness or structural displacement in the crust of the earth. Such features may represent deep seated faults, master fractures and joints sets, drainage lines and boundary lines of different rock formations. Lineaments provide the pathways for groundwater movement and are hydrogeologically very important (Sankar, 2002). Lineaments are important in rocks where secondary permeability, porosity and inter granular characteristics together influence groundwater movements. The lineament intersection areas are considered as good groundwater potential zones. The combination of fractures and topographically low grounds can also serve as the best aquifer horizons. Lineaments have been identified on images through visual interpretation by comparing spatial variation in tone, colour, texture, association, etc. (Figure 4). Areas on either side of lineaments and intersections of lineaments are considered to be favourable for accumulation of groundwater. Figure 4: Lineament map of the study area 3.4 Land use / Land cover Remote sensing data and techniques provide reliable, accurate baseline information for landuse mapping and play vital role in determining land use pattern and changes therein on different cut off dates. The major landuse pattern include cropland (single and double), 1675

7 fallow land, forest area, forest plantations, barren rocky area, land with scrubs and without scrubs etc. following the guidelines of IMSD and NRIS. Cropland includes land for growing the Rabi and Kharif crops and has been identified by the light medium red tone, fine/medium texture varying in size, often rectangular in shape. The forest and forest plantation gives light reddish brown tone with white patches and fine to medium texture with irregular shape and varying size. Although, these areas have good ground water recharge potential, these have been purposefully categorized as poor, keeping in mind that these areas are generally restricted and are not permitted for any ground water exploitation activity (Figure 5). 4. GIS Analysis Figure 5: Landuse/Landcover map of the study area Check dams, nala bunds/plugs, recharge pits and wells etc. provide a good measure of rainwater harvesting structures in the hard rock terrains by arresting run off and increasing the surface area of infiltration. Suitability of these structures depends on various factors, which can be integrated by GIS techniques (M. Girish Kumar, et al. 2008). To assess the groundwater recharge zones in the study area, all the different polygons in the thematic maps were labelled separately. Knowledge based weightages are assigned to each thematic features after considering their importance with respect to groundwater. All the thematic maps were integrated in GIS environment and the polygons have been regrouped into different classes. 4.1 Weight Assignment Thematic layers viz., geomorphology, geology, landuse, lineaments buffer zone and drainage map have been considered for site suitability analysis. Based on the available knowledge on the role of each of these parameters in controlling the occurrence, storage and distribution of groundwater, weightages of 20, 15, 18, 25 and 25 were assigned for geomorphology, geology, landuse, lineament, and drainage respectively. Again each of these layers has further been classified into different classes. Each of the classes, based on its ability to facilitate water infiltration has been given ranks from 1 to 4. Finally, scores have been calculated as the product of the weightage and rank e.g. under the class geomorphology (wt. 20), valley fills have been assigned the rank 4 (wt. 80). The final score has been calculated by the multiplication of the rank and weightage of the class (Table 1). 1676

8 Table 1: Rank, weightage and scores for the various themes for site suitability modeling Geomorphic Unit Weightage 20 Geology Unit Weightage 15 Geomorphic Units Rank Score Litho Units Rank Score Denudational Hills 0 0 (Sheared) Basic volcanic intrusive 3 45 rocks Inselberg 0 0 (Sheared) Chlorite phyllite 3 45 Intermontane Valley 1 20 (Talc) Sericite chlorite phyllite/schist 1 15 Linear Ridge 0 0 Agglomerate 2 30 Pediment 2 40 Pediment Inselberg 1 20 ArkasanI granophyre 1 15 Complex Pediplain Shallow 3 60 Chakradharpur Granite Gneiss 1 15 (Weathered) Residual Hills 0 0 Chert/Chert rhythmite 1 15 Structural Hills 0 0 Conglomerate with sandstone / 3 45 quartzite Valley 3 60 Epidiorite, Hornblende schist, 2 30 Metabasalt, Tuffaceous sediments/chlorite schist Valley Fills 4 80 Mafic intrusive 2 30 Water 0 0 Metabasic intrusions 1 15 Landuse Class Weightage 18 Mica schist with hornblende schist 3 45 Landuse Class Rank Score Newer Dolerite 1 15 Barren Rocky 1 18 Phyllite, mica schist/chlorite/carbon 3 45 phyllite Crop Land 4 72 Phyllite,Carbon phyllite 3 45 Dense Forest 0 0 Quartzite 2 15 Double Crop 4 72 Sandstone and Conglomerate 3 45 Fallow Land 3 54 Shale 3 45 Forest Blank 0 0 Shale, Phyllite, Mica schist 3 45 Forest Plantation 0 0 Singhbhum Granite 1 15 Gullied Land 1 18 Ultramafics (Gabbro Pyroxenite, 1 15 peridotite) Land with Scrub 2 36 Unclassified schist enclave in 1 15 Chakradharpur Granite Land without Scrub 2 36 Open Forest 0 0 Lineaments Unit Weightage 25 Plantation 2 36 Lineament Type Rank Score River 0 0 Lineament (Buffer) Reservoir 0 0 Rural Settlement 0 0 Drainage Unit Weightage 25 Sandy Area 0 0 River/Streams Type Rank Score Scrub Forest 0 0 River/Streams (Buffer) Single Crop 4 72 Stony Waste 1 18 Urban Settlement 0 0 Water Body 0 0 The thematic layers were integrated with one another through GIS using the weighted aggregation method. The following order of sequence was adopted to derive the final integrated map. Geology (I1) + Geomorphology (I2) = O1 O1 + Landuse/Landcover (I3) = O2 1677

9 O2 + Lineament of 50m buffer (I4) = O3 O3 + Drainage of 50 m buffer (I5) = O4 Where I1, I2 and O1, O2 input and output layers respectively. In the first step, geology (I1) and geomorphology (I2) layers were integrated by the union option. The integrated output layer (O1) comprises polygons of the geology layer and polygons of the geomorphology layer and after union it resulted in new polygons having attributes of both the layers. Adding these two layers derived the weight of each polygon in the integrated layer (O1). In the next step, the O1 layer was intersected with the land use layer (I3). In this step, the integrated layer O2 was generated by adding lithology, geomorphology and landuse layers. The O2 layer was integrated with polygons of the lineament buffer zone (I4). Layer I5 involving polygons made around the drainage (buffer zone) was integrated with layer O3 by the union option. The polygons in the integrated layer (O4) contain the composite detail of all the thematic layers together numerically having maximum weight of 397 and minimum weight of 15 with standard deviation Results and Discussion Grouping of polygons of high ranks of all the thematic layers has helped in delineating the sites that are excellent for construction of water harvesting structures. Based upon the standard deviation, the polygons were grouped into classes suited for construction of ground water recharge structures. A Composite Suitability Index (CSI) has been calculated for each composite unit by multiplying weightage with rank of each parameter and summing up the values of all the parameters. Categorization of the CSI is achieved by ranging the CSI into five classes. Class I : Maximum > CSI >= 4σ Class II : 4σ > CSI >= 3σ Class III: 3σ > CSI >= 2σ Class IV: 2σ > CSI >= 1σ Class V: 1σ > CSI > Minimum Where σ = Standard deviation. Figure 6: Suitable Zones for Ground Water Recharge 1678

10 Those polygons, having cumulative weight 15 to (15 to 1σ) in the final integrated layer were classified as Not Suitable for rainwater harvesting. The polygons classified as Poor category have the cumulative weight to , whereas Moderate category has the weights to The polygons classified as Moderate to Good category have the cumulative weight to and Good category have the weights to 397. Thematic map (Figure 6) showing the sites suitable for construction of rainwater harvesting structures suggests that the drainage area and the valley part of the study area are most suitable for construction of rainwater harvesting structures. 5.1 Proposed Ground Water Harvesting/Recharge Structures The site suitability analysis (Figure 6) has helped in locating the suitable sites for the water harvesting structures. Based on the above classification as well as depth to water table map and terrain conditions, a map suggesting the type of structures to be built at various locations has been prepared (Figure 7). The hilly part of the study area with rocky outcrops and steep slopes acts as a high runoff zone. The runoff washes away precious top soil from the hill slopes. Hence there is a need for proper soil moisture conservation measures and rain water harvesting and ground water recharge. Figure 7: Proposed Ground Water Recharge Structures The main suggested recommendations are Boulder Bund: These bunds are low cost small bunds across 1 st to 3 rd lower order streams. They are suitable at the upper reaches where catchments are small and stream courses have been deepened by erosion. They may be made of dry stone masonry or boulders or even brushwood. It is better to have a series of small height bunds. Since the essential function is to stabilize the gully and improve its grade by checking erosion, it is generally recommended that the foot of an upstream gully plug be at the level of the successive downstream bund Check Dams: Check dams are engineered structures constructed across higher order (>3 rd order) streams having minimum average area of 25 ha. These structures are proposed/constructed for checking the stream run off during monsoon and for storage of rain 1679

11 water for specific use beyond the monsoon period. Although these structures are constructed for the purpose of storage of water these may also help recharge of ground water reservoir located in the near vicinity Percolation/Disiltation Tanks: There are the structures built near 3 rd to 4 th order stream to impound surface run off coming from the catchments and to facilitate percolation of stored water in to the soil substrata with a view to raise groundwater level. The minimum size of the site is kept up to 40 ha. While proposing the site for percolation, it was kept in consideration the area is not presently undergoing agriculture practices. Wasteland having adequate fractures to facilitate good groundwater recharge is quite suitable for construction of percolation tanks Recharge Pit: Recharge pits are made either by constructing an embankment across a water course or by excavating a pit or the combination of both. These structures are recommended in single crop areas for providing irrigation to limited area during critical period Sub Surface Dykes: These structures are generally proposed to arrest the lateral groundwater flow. Arresting the flows through the sub surface dykes help in conserving/recharging groundwater resources. The structure should be constructed up to bed rock. 5.2 Conclusion The site suitability modeling for locating the ground water recharge structures using GIS analysis has an added advantage over conventional survey. The multilayer integration viz., geomorphology, landuse, geology, lineament (buffer) and drainage (buffer) gives smaller suitability units as a composite layer. The inter layer ranking and intra layer weightages further intensify the interpolation. Based upon the standard deviation, the polygons were grouped into classes suited for construction of ground water recharge structures. A Composite Suitability Index (CSI) has been calculated for each composite unit by multiplying weightage with rank of each parameter and summing up the values of all the parameters. Categorization of the CSI is achieved by ranging the CSI into five classes. Suitable structures for ground water recharge/harvesting such as boulder bunds, check dam, percolation/disiltation tanks and recharge pits and wells and subsurface dykes were suggested accordingly. 6. References 1. Agarwal A K and Mishra D, 1992, Evaluation of groundwater potential in the environs of Jhansi city, Uttar Pradesh through hydrogeological assessment by satellite remote sensing technique. Journal of the Indian Society of Remote Sensing, 20(3), pp Agarwal A K, Mohan R and Yadav S K S, 2004, An integrated approach of remote sensing, GIS and geophysical techniques for hydrological studies in Rajpura block, Budaun district, Uttar Pradesh. Indian Journal of Power and River Valley Development, 1, pp

12 3. Gupta A., Basu A, and Ghosh P.K., 1980, The Proterozoic Ultramatic & mafic lavas and Tuffs of the Dalma Greenstone Belt, Singhbhum, Eastern India Canadian Journal of Earth Sciences, 17(2), pp Krishnamurthy J and Srinivas G, 1995, Role of geological and geomorphological factors in groundwater exploration: a study using IRS LISS data. International Journal of Remote Sensing, 16(14), pp Krishnamurthy J, Mani A, Jayaraman V and Manivel M, 2000, Groundwater resources development in hard rock terrain an approach using remote sensing and GIS techniques. International Journal of Applied Earth Observation and Geoinformation, 2(3 4), pp M. Girish Kumar, A. K. Agarwal and Rameshwar Bali, 2008, Delineation of Potential Sites for Water Harvesting Structures using Remote Sensing and GIS, Journal of the Indian Society of Remote Sensing, 36( 4), pp National Remote Sensing Agency, (NRSA), 1985, Integrated Mission for Sustainable Development Technical Guidelines, National Remote Sensing Agency, Department of Space, Hyderabad. 8. National Natural Resources Management System/ISRO HQ, 2000, National (Natural) Resources Information System (NRIS) Node Design and Standards, ISRO HQ, Bangalore. 9. National Remote Sensing Agency (NRSA), 2007, Manual for Ground Water Prospects Mapping using Remote Sensing techniques and Geographic Information System Rajiv Gandhi National Drinking Water Mission Project. 10. Rao S N, Chakradar GKJ and Srinivas V, 2001, Identification of groundwater potential zones using Remote Sensing Techniques in around Guntur Town, Andhra Pardesh, India, Journal of Indian Society of Remote Sensing, 29(1 2), pp Sankar K, 2002, Evaluation of groundwater potential zones using remote sensing data in Upper Vaigai river basin, Tamil Nadu, India. Journal of Indian Society of Remote Sensing, 30(30), pp Saraf A K and Choudhury PR, 1998, Integrated remote sensing and GIS for ground water exploration and identification of artificial recharge sites, International Journal of Remote Sensing, Volume 19, Issue 10, pp Saraf A K and Jain SK, 1993, Integrated use of remote sensing and GIS methods for groundwater exploration in parts of Lalitpur District, U.P. International Conference on Hydrology and Water Resources, New Delhi, December