Groundwater Quality Assessment in Maluso, Basilan: Physico-Chemical and Microbiological Perspectives

Abstract

Access to clean and safe drinking water is crucial to public health, especially in rural and semi-urban areas in developing countries, including the Philippines, which face ongoing threats to groundwater quality. This study assessed the physico-chemical and microbiological characteristics of groundwater in Maluso Municipality, Basilan. The groundwater samples were collected from 4 groundwater wells and analyzed using standard methods outlined in the Philippine National Standards for Drinking Water (PNSDW, 2017) and American Public Health Association (APHA, 2017) protocols. Parameters evaluated included pH, total dissolved solids (TDS), electrical conductivity (EC), major ions (Cl⁻, SO₄²⁻, NO₃⁻, Na⁺, K⁺, Mg²⁺, Ca²⁺), and microbiological indicators such as fecal and total coliforms.

The results showed that all measured physico-chemical parameters fell within acceptable limits set by both PNSDW and the World Health Organization (WHO, 2017), indicating geochemical stability and minimal contamination from anthropogenic sources. However, pH values in some samples were slightly acidic (6.00–7.04), and water hardness was classified as soft, which may increase corrosivity and reduce buffering capacity. Critically, all samples failed to meet microbiological safety standards, with fecal and total coliform counts significantly exceeding the permissible limit of <1.1 MPN/100 mL, indicating contamination likely due to inadequate sanitation and unprotected sources.

The findings underscore a dual narrative of chemical compliance and microbiological risk. While the groundwater meets physicochemical safety benchmarks, it is unsuitable for direct human consumption without treatment due to microbial contamination. These results require public health interventions, including point-of-use treatment, community-led water safety planning, and long-term source protection strategies. This study contributes essential baseline data for water quality management in underserved and environmentally vulnerable areas.