GIS-Based Spatial Analysis of Selected Water Quality Parameters in the Southern Part of Lake Sebu, South Cotabato, Philippines

Abstract

This study used a Geographic Information System (GIS) to visualize water quality using Inverse Distance Weighted (IDW) Interpolation that assessed the water quality in the southern part of Lake Sebu, South Cotabato in terms of pH, dissolved oxygen (DO), biochemical oxygen demand (BOD), temperature, total suspended solids (TSS), fecal coliform, and oil and grease. The maps illustrate the trends in water quality that are produced based on DENR’s Water Quality Guidelines and Effluent Standards. The data from 2017 to 2022 revealed that pH, DO, temperature, and TSS stayed within acceptable levels throughout the year, and other parameters showed alarming tendencies such as the increasing amount of fecal coliform and oil and grease. Additionally, this study revealed that the increasing amount of fecal coliform and oil and grease are esulted from anthropogenic activities. The indicators of declining water quality imply detrimental effects on the ecosystems of the lake.

Keywords—Geographic Information System (GIS), Inverse Distance Weighted (IDW), Water Quality, Lake Sebu