This course is an introduction to modeling hydraulic problems using an open-source finite volume method. The modeling procedure for several practical hydraulic examples (including convergence study) was demonstrated using HEC-RAS 2D. This short course took place at the Le Grandeur Palm Resort, Senai from 3-4 October 2020. This short course was organised by Center for Coastal and Ocean Engineering (COEI), Universiti Teknologi Malaysia (UTM) in collaboration with National Water Research Institute of Malaysia (NAHRIM).