Microbial Water Quality Indicators in Molawin River, Los Banos, Laguna Reveals Issues on Land
Ideally, healthy and clean water systems should not contain any microorganisms known to be pathogenic or any bacteria indicative of fecal pollution. The Molawin River is a waterway in the Los Banos subwatershed and falls within the scope of the University of the Philippines Los Banos, which traverses from Mount Makiling down to Barangay Maahas and Barangay Bayog, Los Banos, Laguna where it empties into the Laguna de Bay. The study aimed to establish the baseline microbial water quality of the Molawin creek is the through collection of water samples from three segments, namely Hortorium, Student Union Building, and Barangay Bayog sites during both dry and rainy seasons. The results showed significant anthropogenic influences along Molawin Creek as elevated levels of coliforms are detected across all sampling sites. This are especially seen with proximity to institutional buildings, residential areas, and agricultural lands. Representative isolates were selected for microbial identification using 16s rRNA gene sequencing. The selected isolates reveals the presence of potentially pathogenic bacteria such as Shewanella xiamenensis, Pantoea stewartii, and a possible novel species of Serratia spp. The presence of these bacteria reflect the microbial quality as affected by various activities surrounding the river which may also pose additional risk to the safety of the people. These findings are crucial in crafting measures to restore the Molawin tributary and ensure the safety of these rivers and food that can be harvested, especially the Barangay Bayog segment is heavily populated and serves as a hub for fishing.