Cluster Analysis of Microbial, Physico-Chemical Characteristics, Water Quality Index (WQI) and Trophic Level Index (TLI) for Water Quality Assessment of Beira Lake, Colombo, Sri Lanka

Abstract

This study investigates the water quality and microbial diversity of Beira Lake, Colombo, by analyzing comprehensive physico-chemical parameters and microbial characteristics. Twenty sampling locations were assessed using the Water Quality Index (WQI) and Trophic Level Index (TLI). A key aspect of this research is the use of cluster analysis to group sampling locations based on similarities in microbial communities and water quality parameters. This analysis identified distinct clusters within Beira Lake, highlighting regions with varying pollution levels and microbial diversity. The identification of pollution hotspots, along with the grouping of patterns. Notably, highly polluted outliers (L14, L15, and L18) aligned with known issues such as unauthorized sewer lines, stagnant water, and urban waste sources. The study emphasizes the urgent need for comprehensive pollution mitigation measures to improve water quality and restore the ecological balance of Beira Lake. Immediate interventions targeting both point and non-point source pollution are crucial to addressing the significant environmental stress on the lake. The findings offer critical insights for lake management efforts, underscoring the need for targeted conservation strategies to address pollution sources and enhance water quality.