Philippine E-Journals

Rapid Oxygen Depletion and High Phosphorus Content Indicate Pollution of Lahug River, Cebu City, Philippines

Fleurdeliz F. Maglangit | Ritchelita P. Galapate | Eukene O. Bensig

Discipline: Ecology

 

Abstract:

The present study deals with the physico-chemical analysis of water samples collected monthly from three established sites in Lahug River for a period of six months. The main purpose of the study is to provide baseline data on its physico-chemical characteristics as well as assess its water quality. Statistical tools were used to analyze and interpret the data. The pH, temperature, TDS, DO, nitrates and total P varied significantly (p<0.05) across location. The pH values varied from 7.2 to 7.7 are suitable for the largest variety of aquatic organisms. Water temperature, total suspended solids (TSS), total dissolved solids (TDS) and levels of nitrates were within the permissible DENR guidelines for Class D surface waters. However, the levels of dissolved oxygen (DO), biochemical oxygen demand (BOD) and total P did not comply with the DENR Class D standard for surface waters. Rapid oxygen depletion and high phosphorus content as it traversed downstream indicated that the river is polluted. Major sources of pollution were found to be anthropogenic activities such as indiscriminate dumping of refuse, disposal of waste water from laundry and piggery, and water flow from backyard gardening which uses pesticides or fertilizers. Proper disposal of wastes, establishment of waste water treatment measures, education and public environmental awareness should be done at the community level to reduce the level of pollution in Lahug River.