Understanding groundwater resources in Margajo Watershed, Koderma, Jharkhand

Abstract
Groundwater, which is widespread in occurrence though far from abundant in Jharkhand region, has gained recognition as a major asset to meet basic human needs for potable water and agriculture. In the present study area Agriculture needs during the rabi season can often not be met from surface water resources due to poor management practices. Thus low-yielding unconfined aquifers constitute the only viable source of supply. In entire watershed, groundwater occurs in secondary aquifers consisting primarily in weathered and fractured within the basement. But these aquifers provide low yields. Research priorities, therefore, include more efficient exploration methods, improved characterization of aquifers, better assessment of exploitability and safe yield, and enhancement of sustainable use through artificial recharge. This needs better understanding and management of resources. Ground Water Information System (GWIS) and Geographic Information tools which incorporate spatial and non-spatial details and its analysis provides better understanding and management of groundwater resources.

In the present study, different technique of groundwater exploration has been applied to derive the aquifer geomtery and hydro-geophysical parameters of the aquifer. The all available information has been used to develop the interactive GWIS. It has been also linked with drainage, landuse, socio-economic database prepared in GIS environment. This all exercise gives better understandability of groundwater in watershed perspective. GIS helps in analysing various spatial and non-spatial data related to groundwater whereas GWIS stores data, creates hydrographs, well logs, various chemical diagrams, cross section, fence diagrams, contour maps etc.

Introduction
Groundwater, which is widespread in occurrence though far from abundant in Jharkhand. Growth in population, need to increase the acreage of agriculture and meet the demand of spreading industries, there is urgent need for advance planning and management of resources for its sustainable utilisation. Occurrence of groundwater depends on various parameters such as geology, geomorphology, recharge, aquifer geometry, porosity, specific yield, storage, yield etc. There is a need to create a modern, integrated, and comprehensive Ground Water Information System (GWIS). GWIS and GIS can be used for spatial and no-spatial data analysis, visualization, contouring, attribute tables, statistical analysis integration. This approach is best demonstrated with the United Nations Ground Water for Windows (GWW) package (Karanjack et. al., 1997). GWW is a relational ground water database, a suite of data processing, analysis, interpretation and presentation applications, and an information system.

Study Area
The Maragajo watershed is located north-central fringe of Chotanagpur plateau of Jharkhand. It is located between latitude 240 15'-240 30' and longitude 85015' - 850 30'. The entire study area has areal extent of 150 sq. km. Watershed falls under the administrative jurisdiction of Hazaribagh district of Jharkhand. Geomorphologically, it is parts of undulating pediplain. The topographic height varies from 370 to 400 m from msl. The main river which flows in south-east direction and finally drains into Tilya dam. The drainage patterns are dendritic to sub dendritic and channels represent aggradational fluvial character. Geologically it is a part of Chotanagpur granite gneiss complex.

Methodology
The methodology includes generation and collection of geo-hydrological data and vertical electrical sounding. Laboratory works include land-use mapping and hydro-geomorphic zonation using remote sensing technique, DTM based on topographic elevation and DBTM based on basement depth information derived from VES. Based on geo-hydrological data, hydro-geophysical properties of aquifer, hydro-geomorphic zonation and DBTM, groundwater developmental feasibility map has been prepared. Spatial details such as administrative boundaries, drainage, hydro-geomorphic zonation, land use, groundwater developmental feasibility map and non-spatial data such as demographic details are incorporated in GRAM++ (DST / IIT-B, 2000) GIS. For preparation of GWIS, GWW (Karanjac et al, 1997) software has been used. The GWIS facilitate analysis of geohydrological parameters such as Master Data, Chemistry, Pumping Test, Hydro-graphs, Mapping, Well Log, Cross Section, Fence Diagrams, Step Draw-down Test, Grain Size Curve, Abstraction etc.

Discussion
The present information system has been developed using GRAM++ GIS and GWW. Database in GIS will facilitate the planner for knowing the various option available with different criteria. This will help in sustainable planning and management of groundwater in watershed perspective whereas GWIS will facilitate the technical expert to understand and analyse the groundwater. It has been described in following paragraphs

Geographic Information System (GIS)
For sustainable planning and management of groundwater besides geo-hydrological database depicting in time and space, its judicious utilization and management needs spatial and non-spatial database on other interacting natural resources. It is linked to entire eco-system of watershed. In the present study, primarily drainage system, surface water resources, land use and hydrogeomrphic information have been derived with the help of remotely sensed data. These maps give the spatial distribution. Further, groundwater need assessment and development also depends on the population and its distribution, industrial growth areas. These non-spatial details are also required to incorporated the database. Therefore GRAM++ GIS framework has been used to integrate the different non-spatial and non-spatial details for better assessment of need and working out possibility of utilization of groundwater and other viable alternative. The complexities of the data make a Geographic Information System (GIS) a valuable tool for use in the planning and management of groundwater because of its ability to create, store, analyze, and present relational data.

Table 1.1: Master Data Structure
Data Entry	No. of Characters	Data Type	Format	No. of Decimal digit	Unit
Well Ident.	10	Well
Description	50	Character
District	20	Character
Village	20	Character
Owner	20	Character
X	10	Numerical(Dim)	Fixed	2	Meter
Y	10	Numerical(Dim)	Fixed	2	Meter
Z	10	Numerical(Dim)	Fixed	2	Meter
ZM	10	Numerical(Dim)	Fixed	2	Meter
Map Sheet No.	10	Character
Year	10	Character
Geomorphology	20	Character
Aquifer Type	20	Character
Watershed	20	Character
Block	20	Character
Aquifer Material	20	Character
Relative Geomorphology	20	Character
Water table	10	Numerical(Dim)	Fixed	2	Meter
Depth of Basement	10	Numerical(Dim)	Fixed	2	Meter
Aquifer Resistivity	10	Numerical	Fixed	2	Ohm-M
Date of Observation	10	Date	dd.mm.yy

**Table 1.2: Chemical Data Structure**
Data Entry	No. of Characters	Data Type	Format	No. of Decimal digit	Unit
Well Ident.	10	Well
Ca	10	Numerical(Und)	Fixed	2
Mg	10	Numerical(Und)	Fixed	2
Na	10	Numerical(Und)	Fixed	2
K	10	Numerical(Und)	Fixed	2
Fe	10	Numerical(Und)	Fixed	2
Mn	10	Numerical(Und)	Fixed	2
Hco₃	10	Numerical(Und)	Fixed	2
So₄	10	Numerical(Und)	Fixed	2
Cl	10	Numerical(Und)	Fixed	2
No₃	10	Numerical(Und)	Fixed	2
No₂	10	Numerical(Und)	Fixed	2
Po₄	10	Numerical(Und)	Fixed	2
F	10	Numerical(Und)	Fixed	2
B	10	Numerical(Und)	Fixed	2
Sio₂	10	Numerical(Und)	Fixed	2
TDS	10	Numerical(Und)	Fixed	2
Hardness	10	Numerical(Und)	Fixed	2
Alkalinity	10	Numerical(Und)	Fixed	2
Conductivity	10	Numerical(Und)	Fixed	2
PH	10	Numerical(Und)	Fixed	2
Ca	10	Numerical(Und)	Fixed	2
Cations	8	Numerical(Und)	Fixed	2
Anions	8	Numerical(Und)	Fixed	2
SAR	8	Numerical(Und)	Fixed	2
BalErr	8	Numerical(Und)	Fixed	2

In the present study, following themes have been taken into consideration in GRAM++: Village boundary and demographic characteristics, drainage, transportation network, land-use, hydro-geomorphology, surface water, topography, groundwater development feasibility etc. Based on the different spatial and non-spatial database, related SQL has been build to facilitate the non-specialist so that they can search the different priorities with different situation. Final data has been structured in Access format and it can be upgraded and linked to GIS database for the analysis. In the database, village has been selected as a unit (Fig. 1.1). All thematic layers such as land use (Fig. 1.2), hydro-geomorphic map (Fig, 1.3), drainage (Fig. 1.4), surface water, topography (Fig. 1.5), Depth of Basement Topographic Model (Fig. 1.6), groundwater feasibility are separately available within watershed. From the different thematic layers, village wise tabular information has been extracted and master database has been prepared and it has been linked to village database which also includes demographic details. The results indicate that 13.33 per cent area of the watershed under rabi crop (Table 1.1) and majority of crops are irrigated through the dugwells. Rabi crops are mostly in the outer peripheral of village. The surface water body layer gives the idea of its areal distribution. It has been observed that watershed is harvesting only 27.5 per cent of total available potential. The groundwater feasibility layer provides (Table 1.2 & 1.3) the information on the suitability of groundwater development at particular location within the watershed. The results based on hydro-geomorphic mapping (Table 1.4) indicate that groundwater 69 per cent of the watershed area is suitable for groundwater development through dug-well cum bore well. These village wise extracted natural resources database are linked with the other socio-economic parameters for deciding the development of surface and groundwater other than technical criteria.

Table 1.3: Pumping Test Data Structure
Data Entry	No. of Characters	Data Type	Format	No. of Decimal digit	Unit
Well Ident.	10	Well
Test Date	10	Date	dd.mm.yy
Distance	10	Nummerical(Dim)	Fixed	2	Meter
Avg P Rate	15	Nummerical(Dim)	Float	7	m3/day
Duration	15	Nummerical(Dim)	Float	7	m3/day
Insat Th	15	Nummerical(Dim)	Float	2	M
Transmissivity	15	Nummerical(Dim)	Float	7	M2/day
Storage	15	Nummerical(Dim)	Float	7
Leakance	15	Nummerical(Dim)	Float	7	1/day
ConfAqthickness	10	Nummerical(Dim)	Fixed	2	M
B	10	Nummerical(Dim)	Fixed	2	m
L	10	Nummerical(Dim)	Fixed	2	M
D	10	Nummerical(Dim)	Fixed	2	M
L1	10	Nummerical(Dim)	Fixed	2	M
B	10	Nummerical(Dim)	Fixed	2	M
D1	10	Nummerical(Dim)	Fixed	2	M
Standard Error	10	Nummerical(Dim)	Fixed	2	M
Mrthod	25	Character

Table 1.4: Hydrographs Data Structure
Data Entry	No. of Characters	Data Type	Format	No. of Decimal digit	Unit
Well Ident.	10	Well
Aquifer	30	Character

Table 1.5: Well Log and Lithology Data Structure
Data Entry	No. of Characters	Data Type	Format	No. of Decimal digit	Unit
Well Ident.	10	Well
Drill. Dates	25	Character
SWL	10	Numerical (Dim)	Fixed	2	Meter
DWL	10	Numerical (Dim)	Fixed	2	Meter
Drill. Method	30	Character
ConcrBlockDx	10	Numerical (Dim)	Fixed	2	Meter
ConcrBlockDy	10	Numerical (Dim)	Fixed	2	Meter
ConcrBlock H	10	Numerical (Dim)	Fixed	2	Meter
Above GS	10	Numerical (Dim)	Fixed	2	Meter
Vert.Scale	10	Numerical (und)	Fixed	1
Hor.Scale	10	Numerical (und)	Fixed	1

Ground Water Information System (GWIS)
An understanding of the hydrogeologic conditions of an aquifer system is necessary for the conceptualization the planning and development of groundwater. The developed GWIS may be used for reconnaissance studies prior to taking up any detail field investigations, data interpretation after field programs and predictive studies. GWIS have comprehensive data structures that allow for the utilization of various types of data describing hydro-geologic parameters of aquifer system. It describes temporal variability of point location data as well spatial variation within the domain. GWIS covers the relevant hydro-geologic parameters. The System has provision to design the layout in own suitable manner. It has ability to create, store, analyze, and present relational data.

The following parameters have been taken into consideration for establishment of GWIS using GWW software package.

Location parameters for wells, sampling points, springs etc. (Well identification code, SOI code, owner, use of well, village, block and district name, X and Y coordinates, Ground surface elevation, regional belonging (basin/ watershed), geology, aquifer types, types of well )
Water Level Data : new observation wells, observation wells of CGWB and SGWB
Lithology, Stratigraphy
Hydro-geological and Hydro-geophysical Parameters [aquifer characteristics, depth and thickness of aquifer, effective porosity (approximated), aquifer resistivity]. Transmissivity, hydraulic conductivity and leakage coefficient of aquifer has not been included due to non-availability of sufficient data.

The data structure files for inputting the raw data has been given Table -2.1 to 2.5

The following are the data retrievals and presentations using the database and information system created with the GWW software

Location maps showing points ( observation well, vertical electrical sounding sites, surface elevation, basement depth observation location), lines and areas ( watershed boundary )
Various contours maps ( surface elevation, depth of basement, water level, aquifer resistivity )
Lithological cross-sections ( in present study it is electrical log )
Fence diagrams showings the lithology, stratigraphy and water levels or heads

The available database contains information about water table of more than 75 sites, vertical electrical sounding response of 50 sites, 10 years meteorological data, data of hydro-graphs station mentioned by Central Ground Water Board and State Ground Water Board. The groundwater related data collected and generated in GRAM++ has been also re-arranged in the GWW domain. The data import to GWW is simple and it imports data in asccii format. In the study area authentic bore litholog data was not available where as interactive display of well log, cross-section and fence diagram is one of important facilities available in GWW. In the present study, the electrical log obtained through interpretation of VES response from individual sites have been converted into litho-log/ section and it has been inputted in GWIS as pseudo litho-log.

In the entire database, well identification number (ID) is unique number through which data on different geo-hydrological parameters can retrieve and analyzed in specific application module available within the GWIS. The single GWIS data file of Margajo watershed, Koderma, Jharkhand has been internally structured as Master Data, Chemistry, Chemistry, HGWL, Hydrographs, and Welllog. From database in GWW application like display of Master Data (Fig. 2.1), Chemistry (Fig. 2.2), Hydrographs (Fig. 2.3), Mapping (Fig. 2.4), Well Log (Fig. 2.5), Cross Section (Fig. 2.6) and Fence Diagrams (Fig. 2.7) can be performed in users defined format. The details of information available in GWIS is given below

Master data: Master data of 125 sites contains well identification, X, Y, Z, ZM, name, watershed, district, block, geology, aquifer type, water table, basement depth, aquifer resistivity.

Map: Location of water table observation sites and VES sites, Topographic map, basement depth map, iso-resistivity map, water table contour map.

Lithology and Construction: well, X, Y, Z, ZM, vertical scale, horizontal scale, and lithology, drill hole.

Water Level Data: Well identification number, date of observation (yy/mm/dd), Level

The present GWIS does not support 3-D display of contours. Further, analysis between two spatial themes is also not possible within the GWIS. For this purpose GIS has been used to derive the village wise information from different thematic maps. At present GRAM++ and GWW is not interfaced.

Conclusion
The Geographic Information System (GIS) and Ground Water for Window (GWW) has helped in creating interactive ground water information system. The scattered non-standard data on different parameters available with different user agencies have been well arranged in retrievable format in GWW. Now the GWIS of Upper Barakar basin is providing arranged and structured database. The created information system in GIS and GWW may be used to the standard ground water modeling package. However due to lack of interface between GIS package and GWW, the data related to other natural resources can not be actively linked together. There is further scope for development of interface between GIS (in present case GRAM++).

At present there is no common platform for creation of GWIS in the country. The apporach adopted in the creation of GWIS for Maragajo watershed may be used in the other parts of Country. GIS and GWIS of Upper Maragajo watershed has provided opportunity to understand groundwater parameters in integrated manner.

Acknowlegement
Authors are thankful to Prof. (Dr.) Amitabh Ghosh, Director, Bihar Remote Sensing Application Center, Patna for giving constant encouragement for research work. Authors are thankful to Deptt of Science and Technology, Govt. of India for providing financial assistance to the project and arranging training in GIS based Ground Water Modeling under NRDMS-UNDP programme. Authors are also thankful to Dr. Jasminko Karanjac for providing training and GWW software.

References

BCST/DST (1999). Aquifer Geometry analysis and Natural Resources Management in GIS Environment, Upper Barakar Basin, Koderma, Bihar, Unpublished report of BCST, Patna
Bhattacharya B. B., ( 1990 ). Hydrogeological and Ground Water Resources of Hazaribagh, District, Bihar, Unpublished Report of Central Ground Water Board, Patna.
Braticevic Dusan and Karanjac Jasminko (1997). Ground Water for Windows (ver. 1.31) software and manual, Department for Development Support and Management Services, United Nation.
DST - CSRE (2000). GRAM++ Window based GIS Package, Deptt of Science & Technology, New Delhi.

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