WATER TEMPERATURE SIMULATION OF OWENA RIVER AT OWENA DAM SITE USING HEC-RAS MODEL

Abstract

quality. Temperature affects almost all processes and other water quality parameters. The processes
include stratification, biotic processes and chemical fate processes. Water temperature affects other water
quality parameters such as Dissolved Oxygen and Biochemical Oxygen demand (BOD). Today, with
recent technological advances, several computer-based hydrologic/water quality models have been
developed for applications in hydrologic modelling and water resources studies. The HEC-RAS
(Hydrologic Engineering Centers Rivers Analysis) model performs one-dimensional steady flow,
unsteady flow, sediment transport/mobile bed computations, and water temperature modeling. This study
tries to simulate the water temperature of Owena dam using HEC-RAS model. The input data for the
simulation are geometric data, steady flow data, and meteorological data. Input data was entered in the
various data editor windows and interfaces of the model in a logical sequence using a series of
components parts of the model that direct the program to accept, process, compute and store various
parameters and their corresponding values. The results obtained were compared with the observed
temperature data of Owena dam for the months of January, June and July. The result of the observed and
simulated water temperature shows a correlation of determination (R²) of 0.92, 0.83 and 0.6 for the
months of January, June and July respectively. From the result, it can be concluded that HEC-RAS can
actually simulate water temperature of Owena River in Ondo state of Nigeria.