Shantha Kumar Dhanush; Mahadeva M Murthy; Ayyappa Sathish; Rinku Verma
Abstract
A study was conducted on Gubbi Lake to investigate the water quality using water quality indices (WQI), multivariate statistical technique and geospatial technology. 20 lake water samples were collected during pre-monsoon and post-monsoon seasons for examining physicochemical parameters. The results ...
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A study was conducted on Gubbi Lake to investigate the water quality using water quality indices (WQI), multivariate statistical technique and geospatial technology. 20 lake water samples were collected during pre-monsoon and post-monsoon seasons for examining physicochemical parameters. The results revealed that Biochemical Oxygen Demand measured in milligram per litre (8.5 mg/l and 5.3 mg/l in pre-monsoon and post-monsoon season respectively) exceeded the normal range of 5 mg/l and ammonia (1.24 mg/l and 0.6 mg/l during pre-monsoon and post-monsoon season respectively) exceeded acceptable limits recommended by the Bureau of Indian Standards in both seasons. The Canadian Council of Ministers of Environment WQI ranged from 66.7 to 81.13 with a recorded mean of 74.22 imparting ‘fair’ conditions. Apart from Kelly’s index, all the irrigation WQIs designated majority of water samples as suitable for irrigation. All the industrial WQIs conveyed the tendency to corrode except Larson and Skold index that indicated corrosion potential. The principal component analysis effectively diminished the complex water analysis dataset into 6 principal components each for pre-monsoon and post-monsoon seasons which explained 87.85 % and 89.80 % of total variance respectively. These components identified the pollution sources as primarily originating from anthropological activities like agricultural runoff, domestic sewage waters and natural weathering of rocks. Hence, the combined approach using above-mentioned methodologies proves to be indispensable in evaluating surface water quality. The findings of this study further underscore the necessity for prompt action by decision makers for well-being of both environment and public health.
