Surface water quality assessment of Amingaon (Assam, India) using multivariate statistical techniques

Abstract

Abstract The pollution of surface water has become a global environmental issue. Monitoring of surface water is essential to know the current status of water quality and maintain it at certain desirable level. In this study surface water quality of Amingaon has been analysed. Amingaon is a locality in North Guwahati (Assam, India). In last few decades’ the locality has undergone rapid and uncontrolled development activities which have a detrimental impact on its ecology and environment. Samples were collected from 12 lakes and analysed for 24 parameters namely temperature (T), pH, electrical conductivity (EC), turbidity (Tur), total suspended solids (TSS) and total dissolved solids (TDS), total alkalinity (TA), total hardness (TH), chloride ion (Cl−), fluoride (F−), sulphate (SO42−), sodium (Na+), potassium (K+), calcium (Ca2+), dissolved oxygen (DO) biochemical oxygen demand (BOD), chemical oxygen demand (COD), ammonium nitrogen (NH3-N), total Kjeldahl nitrogen (TKN), nitrate (NO3−) total phosphorus (TP) and available phosphorus (AP). Multivariate statistical techniques were used for the assessment of water quality. Cluster analysis (CA) was used for classification of water quality parameters and principal component analysis (PCA) was used to identify the sources of pollution. CA grouped all the water quality parameters in three cluster. PCA resulted in six useful components which explained 90.54% of the total variance. Based on overall study it was concluded that the sources of pollution of lakes were the use of fertilizers, storm water runoff, land development and domestic waste water discharge. Trophic state of lakes was also evaluated using Carlson's Trophic State Index (TSI).