Development of an Index of Aquifer Water Quality within GIS Environment

The changes in human population often correspond with change in land use, including expansion of urban areas, agriculture andincreasing industrialization, which necessitate increasing the available amount of drinking water. as the surface water sources areunder the pressure of pollution, it has become necessary to use groundwater at an increasing rate. groundwater recharge can beabundant in the alluvial plains where the urban areas are often located. such areas can face danger of pollution of groundwater andthe changes in land use are likely to result in change in groundwater quality. keeping these aspects in view, it was planned todevelopment a groundwater water quality index in the ganga-yamuna interfluve area of northern india, the objective of the presentstudy is to develop the index of aquifer water quality (iawq) inside the geographic information system (gis) environment, whichcan be used by the field investigators and modeler's in assessing the groundwater vulnerability. the formula to estimate the iawqindex is adopted from the procedure suggested melloul and collin (1998). the procedure developed for this involves weightsassigned to these 8 parameters as per their analytical hierarchy in violating the (drinking water) standards and not as an arbitrarymeans (as taken by melloul and collin). the suggested procedure can be extending to include more number of chemical parametersas necessitate in individual case studies. in the modified procedure presented in the present study, the number of measured chemicalparameters n is taken as 8 (cd, mn, pb, fe, no3-, total alkalinity, tds and ca2+) as against n=2 (chloride and nitrate) as taken inthe melloul and collin's work.