Water Quality and Pollution Status using Principal Component Analysis of Lake Nsezi in Richards Bay, Kwazulu-Natal, South Africa

Abstract

The water quality of Lake Nsezi in Richards Bay, South Africa was investigated for the possible influence of anthropogenic activities around the lake. Lake water was sampled for a period of one year from May 2014 to May 2015. Physicochemical and bacteriological analysis were compared to regulations of WHO, USEPA and DWAF WQG for aquatic environment and domestic use. Physicochemical parameters measured were within the recommended specifications as per WHO, USEPA and DWAF guidelines for aquatic environment and domestic use at the exception of TDS, Cl and few heavy metals such as Al, Cd, Cu, Fe and Mn. The average content levels for these parameters were: 530±167 mg/L (TDS), 135±92 mg/L (Cl), 0.079±0.11 mg/L (Al), 0.171±0.66 mg/L(Cd), 0.38 ± 0.50 mg/L (Fe), 13.6±15.33 mg/L (Pb). Principal component biplots positively showed some strong and moderate metal loadings of 0.564 (Fe), 0.552 (Pb), 0.928 (Na), 0.893 (Mg), 0645 (Sr) and 0.772 (K) at a variety of sites. Bacteriological parameters content investigated were all above the WHO, USEPA and DWAF guidelines for domestic use for E. coli, heterotrophic plate counts and total coliform counts.