Catchment Characterization to Understand Flooding in Cagayan De Oro River Basin in Northern Mindanao, Philippines

Ruel  R. Cabahug,; Wendell  D. Talampas,

Catchment Characterization to Understand Flooding in Cagayan De Oro River Basin in Northern Mindanao, Philippines

Abstract:

The Cagayan de Oro River Basin is the second largest river basin or watershed in Northern Mindanao, occupying an estimated area of 1,373.84 sq. km. The drainage basin was delineated using Shuttle Radar Topographic Mission (SRTM) 90m digital elevation model (DEM). Geographical features were derived from the DEM using geographic information system (GIS) to perform a morphometric analysis of the river basin and evaluate various parameters of linear, areal and relief aspects. Linear aspect analyses showed that the drainage basin has a 7th order stream with a bifurcation ratio of 1.8. Areal aspect demonstrates that the basin has a drainage density of 2.29 km/mk2 with a circularity and elongation ratios indicating that the basin is less elongated. Relief aspect of the river basin indicates that it has a resistant basement rock formation and susceptible to erosion. Overall evaluation of the various basin parameters revealed that the inherent features of the river basin has made it naturally liable to flooding with anthropogenic activities exacerbating the extent of risks.