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3.4 Groundwater Quantity Improvement Measures 
At places where the groundwater is over exploited 
some measures can be undertaken which would improve 
the groundwater conditions. 
3.4.1 Water harvesting structures': Water harvesting 
structures like check dams, percolation tanks can be 
constructed across drainage networks so that rain water, 
instead of flowing as run-off would get collected and 
percolate underground. This would slowly increase the 
groundwater table and these structures would act as 
recharge structures. Suitable sites for construction of 
percolation tanks and check dam can be identified by 
performing spatial analysis in GIS by using site 
suitability criteria (Novaline et al, 1993). Various 
alternative sites can be obtained as a result of such an 
analysis and these alternatives can also be ranked as first 
best, second best and so on. 
3.4.2 Change in cropping pattern: Emphasis on high 
water consuming paddy and wheat need to be shifted to 
growing cereals, requiring less water like maize etc. 
Land suitability for various crops which require less 
water can be analysed in GIS by finding out if a crop can 
grow under the terrain and weather conditions prevailing 
in that region. 
3.4.3 Artificial recharge measures: Artificial recharge 
methods like spreading methods, injection methods, 
induced recharge methods, etc., can be introduced. For a 
particular area which of these methods are suitable can 
be analysed in GIS. 
At places where under exploitation is prevailing 
some developmental programs (for example change in 
crops which require more water and giving more 
returns) can be sorted out so that the full potential of 
groundwater resource is utilised without exceeding the 
safe limits. 
4.0 MODELLING FOR GROUNDWATER 
QUALITY 
Historical geochemical data like EC, pH, SAR etc. 
of the water samples taken from bore/dug wells can be 
used to assess the suitability of water quality for 
agriculture/drinking water/industrial purpose based on 
standard specifications. Such an analysis can be 
attempted in GIS by assigning suitability ranking for 
different ranges of EC, pH, SAR, Fluorine, Fe, Cl etc., 
(Novaline et al., 1993). 
If the water quality is found to be unsuitable then 
the sources of contamination like point source, diffuse 
source or saline water intrusion etc., can be found out. If 
source of contamination is a point source, for example 
waste disposal site, site selection for future waste 
disposal sites can be identified by GIS analysis. If it is a 
diffuse source say, cultivated areas, then, changes in 
cultivation practice and nutrient supply can be adopted. 
Land suitability analysis for different crops which do not 
require or require less amount of harmful nutrients can 
be performed in GIS. 
5.0 CONCLUSION 
The aim of groundwater management is to adjust 
landuse systems to the site properties, to maintain a high 
level of groundwater recharge without inducing an 
increase in erosion, acidification, leaching of chemicals 
and overland flow. 
Sustainable Groundwater Management System 
which is envisaged here considers both groundwater 
quantity and groundwater quality in terms of recharge of 
groundwater, extraction of groundwater within the safe 
limits, planning of crop rotation to reduce unproductive 
water consumption, crop production and environment 
effects of groundwater such as nitrate leaching etc. has 
to be based on a site specific management. GIS is an 
excellent tool to model such (site specific) spatial 
problems. This paper emphasises on the useful appli 
cation of GIS techniques in modelling the issues related 
to sustainable groundwater management problem. 
REFERENCES 
Novaline Jaga R.M., Sundaram A. and Natarajan T. (1993). 
Wasteland development using Geographic Information System 
techniques. International Journal of Remote Sensing, Vol. 14. 
No. 17, pp. 3249-3257. 
Selige Th., Friedrich K., Vordeebrugge Th., Reinartz P. and 
Peter M. (1994). Groundwater management by monitoring 
water gathering areas using remote sensing and GIS. SPIE 
(The Society of Photo-Optical Instrumentation Engineers). 
Vol. 2314. pp. 292-299. 
Sharma R.K. (1987). A text book of Hydrology and Water 
Resources Engineering. Dhanpat Rai and Sons, Delhi - 
110006, pp. 569.