Assessment of Soil Erosion, Sediment Transport and Deposition along Cagayan de Oro River

Abstract

The study focuses on soil erosion and the transport and deposition of eroded sediments along Cagayan de Oro River. Its main thrust is to assess the extent of soil erosion considering rainfall pattern and vegetation growth and on sediment transport and deposition considering the turbidity of the water, river velocity and the type of soil extracted at certain parts of the river. Rainfall data is taken from the hydrologic records of PAG-ASA-DOST at El Salvador City. Site visit and inspection were conducted to determine the abundance or scarcity of vegetation growth. Soil extracted from the channel bed and water samples taken from the river were brought to laboratories accredited by the Department of Public Works and Highways for grain-size analysis and turbidity tests. River velocity was determined by crude method. The results of the study revealed that the riverbanks of Cagayan de Oro River are moderately eroded. Turbidity of the water is a positive indicator that quite a large amount of fine-grained sediments are present and transported by Cagayan de Oro River. Settlement of large sediments occurs at the upstream part of the river in Cala-Cala, Macasandig. Silt and sand settled at the area near Marcos Bridge and at Isla Bacsan.