HEC-RAS (Hydrologic Engineering Center’s River Analysis software) is a one-dimensional computer program that models the hydraulics of water flow through natural rivers and other channels . It was used to modify the existing culverts on River Omi which in the past years and of recent has inundated its surroundings. The hydrological data was also measured and used as an input to the model. The model was used over MIKE11, flovial and other hydraulic mathematical model because of its high visual capability and complete output with detailed .
The results showed and confirmed that the existing culverts at the considered cross-sections could no longer accommodate the river’s discharge. A box-culvert spanning 7.2m with a rise of 1.8m will be adequate and economical to replace the existing ones. The existing wing wall was sufficient for the modified cross-section.