assessment of impact of urbanization on groundwater resources using gis techniques- case study of hyderabad, india

hyderabad is one of the fastest growing indian megacities which have significant impact on itsenvironment. the surface and groundwater resources are severely affected by uncontrolled expansion anddensification of the city. for the better understanding, recovery and to prevent future deterioration of thesesignificance resources, it is necessary to have knowledge of the impact of urban growth in various ways onenvironment. historical groundwater level and quality data obtained from different sources as well as by fieldstudy data is used for this analysis. in some cases missing data points were interpolated and verified byproviding certain criteria. the map of rate of groundwater level change per year showed the locations ofrecharge activity by sewage and other effluents as well as overexploitations by industrial and some uppermiddle class residential areas. the results obtained from groundwater quality analysis are then compared withthe bis (bureau of india) as well as who (world health organization) standards for drinking water. it hadbeen observed that many water samples had heavy metal elements and bacterial formation above permissiblelimits and it is not suitable for drinking purpose. the water samples obtained from locations which do notqualify for drinking water use according to who as well as bis standards are identified. these results are thenoverlapped with map of rate of groundwater level change to establish the relation between urban groundwaterrecharge and its effect on groundwater quality.