Mr. D.S. Sampath, Lecturer, Mr. Ashan Madhushka and Mr. Tharanga Buddhimal, final year students attended training workshop on Watershed and River Flow Modeling using HEC-HMS and HEC-RAS on 24th and 25th April 2017 at the Open University of Sri Lanka, Colombo. This workshop was organized by section C of Sri Lanka Association of Advancement of Science (SLAAS). Dr. Jayantha Obesekara, Chief Modeler, South Florida Water Management District and Affiliate Research Professor, Florida Atlantic University, USA, conducted workshop as resource person. The workshop covered the following topics including computer based simulation activities: (i) Water modeling using HEC-HMS, (ii) Water Modelling using HEC-RAS, (iii) QGIS and (iv) HEC-DSSVue.