Spatial modelling approach to water pollution monitoring in the sugar belt of Maharashtra along the Krishna river Conclusions GIS has been utilised in the storage and retrieval of attribute data such as water quality parameters (pollution loads), population density and fertiliser consumption over the spatial database (map) of Satara-Sangli stretch in the Krishna basin. This database was useful in motoring the trend of pollution load and population growth in the entire watershed between 1984 to 1997. With the aid of map comparison utility in GIS pollution map could be compared with the population, fertiliser and industry location maps. Satara-Sangli stretch of the Krishna river is polluted grossly by the human-induced activities in the subwatersheds. The factors for acute pollution of water are:- the intensive use of fertilisers and pesticides in the agricultural land, growth of medium to big size sugar and distillery factories and very high growth of population leading to high domestic load from urban setup. Amongst the physical parameters turbidity values increased and the same results were witnessed after 1990 for chemical parameters such as BOD, COD, Na, Mg, Ca, Cl, TKN and sulphate. For all the pollutants load values increased abruptly for the subwatersheds along the downstream direction. There has been a good relationship between the pollution parameters with the population density. About 32 lakhs people got exposed to the pollution in 1991. The growth of people synchronised with that of the growth in industries. About 8 major sugar factories were responsible for the most of industrial effluents. Of all sources, the share of agriculture to water consumption and water pollution was the highest. Agricultural sources contributed to 91 % of total waste discharge while the same for domestic and industrial sources were 4.5 % each. It is very much indispensable that some standard economically feasible technologies be adopted to mitigate and reciprocate the process of water quality degradation, and restore the quality back to its normal. The river zonation suggested in this paper on the basis of subwatershed approach is fairly better in terms of areal coverage and pollution control. References
I am thankful to the Director, Indira Gandhi Institute of Development Research (IGIDR), Mumbai and United Nations Development Programme (UNDP), New Delhi for providing me research scientist fellowship under UNDP's research project on Rio Earth Summit. My discussion with the director was useful during the analysis stage of this work. Figures: 
Framework for Monitoring River Basin |