Document Type : Research Paper


1 Civil Engineering Department, University of Technology, Baghdad 10066, Iraq

2 Civil Engineering Dept., University of Technology-Iraq, Alsina’a street, 10066 Baghdad, Iraq.


This work aims to use the digital elevation model (DEM) or 3-Dimensional surface to model and analyze the water flow in the Tigris River. The first stage of this study is based on filed data acquisition survey at 38 stations.  These stations were adopted to implement the one-dimensional steady and unsteady numerical flow models. The HEC-RAS software was used to implement these models. The most important results of the steady-state model were that the maximum discharge and velocity and minimum flow area were 638.17 m3/sec, 2.12 m/sec and 301.42 m2 respectively. These values occurred at station 66+700. While, the minimum discharge and velocity and maximum flow area were 504.5 m3/sec, 0.13m/sec and 4758.13 m2 respectively. The results of unsteady state were analyzed based on the recorded discharge in the year 2018. The maximum and minimum discharge (flow velocity) were 638.12 m3/sec (2.42 m/sec) at the stations 94+666+7 and 635.57 m3/sec(0.14 m/sec) at station 00+00, respectively. The maximum and minimum Froude number were 0.52 and 0.02 at stations 94+666+7 and 04+800, respectively. These results help to identify the flow choking areas that cause defects. In addition, it can be the base for determining the critical sedimentation stations in which the bed level rises and aggravate the flow choking problem within the considered reach of the Tigris River.


  • Model has been operated to steady state based on the recorded discharge.
  • Model has been operated to unsteady state based on the recorded discharge (2012-2017) years.
  • HEC-RAS can use successfully for modelling the ecosystem behaviour of Tigris River within a steady area.


[1] Arun, D. I., Aryadutt, O., & Prajith, K. K. P. Aerodynamic Decelerator Atmospheric-Entry Module (ADAM) FOR MARS. ISHMT Digital Library. Begel House Inc,2017.
[2] Allison, J., Amako, K., Apostolakis, J., Arce, P., Asai, M., Aso, T. Barrand, G. Recent developments in Geant4. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 835, 186–225,2016.
[3] Mahmoud Saleh Al-Khafaji . Evaluating the Hydraulic Performance of Al Msharah River.Eng.&Tech. 26, 3, 2008,338.
[4] Ala Hassan Nama . Estimating the Sediment Transport Capacity of Tigris River Within Al Mosul City. Journal of Engineering 17, 3,2011,473.
[5] Ala Hassan Nama and Zahraa Abdulhussain , Riverbed Scour Due to Accumulation of Floating Debris onAl-Msharah Bridge Piers. Al-Nahrain University, College of Engineering Journal (NUCEJ) 18 ,.1, 2015 16 -25.
[6] Ala Hassan Nama . Distribution of Shear Stress in the Meanders of Tigris River Within Baghdad City. Al-Nahrain University, College of Engineering Jou rnal (NUCEJ).18 ,1, 2015,26 - 40.
[7]  Abdelbasset, Midaoui and Lahrach A. and Chaouni_ Adel A. and Bourak A. and Benaabidate L., Integration of GIS and HE-RAS in flood modeling of the ouergha river, northem Morocco, 11,.2,2015.
[8] Dang & K.Lalit, Application 0f remote sensing and GIS-based hydrological modelling for flood risk analysis:a case study of District8, Ho Chi Minh city, Vietnam, Published by Informa UK Limited, trading as Taylor & Francis Groop,2017.,
[9]  Sharma and Mujumdar  Floodplain Zoning Simulation by Using HEC-RAS and CCHE2D Models in the Sungai Maka River'
[10] Traore &others, Using of HEC-RAS Model for Hydraulic Analysis of a river with Agriculture Vocation :A CaseStudy of the Kayanga River Basin, Senegal, American Journal of Water Resources, 3 ,5, 2015,147-154.
[11] F. Onen and T. Bagatur, Prediction of flood frequency factor for Gumbel distribution using regression and GEP model,Arabian Journal for Science and Engineering, 42, 9,2017, 3895–3906.
[12]  T. Bagatur and F. Onen, “Development of predictive model for flood routing using genetic expression programming,” Journal of Flood Risk Management,  11, 2018, 444–454.
[13]  N. S. Romali, Z. Yusop, and A. Z. Ismail, Application of HEC-RAS and Arc GIS for floodplain mapping in Segamat town, Malaysia, International Journal of GEOMATE, 14, 43, 2018,125–131.
[14] Alwan, Imzahim A, Zina W Samueel, and Qassim K Abdullah. Accuracy Assessment of Digital Elevation Models Produced From Different Geomatics Data.Engineering and Technology Journal 38 , 11 , 2020,1580–92.
[15] Maatooq, Jaafar S, and Luay K Hameed. 2D Model to Investigate the Morphological and Hydraulic Changes of Meanders,Engineering and Technology Journal 38 , 1, 2020,9–19.
[16] Karim, Ibtisam R, and Sarmad A Sahib. The Hydraulic Analysis of The Irrigation Network of The Proposed Taq-Taq Dam Using EPANET Software. Engineering and Technology Journal 37 , 10 ,2019, 429–34.
[17]  C. B. Khalfallah and S. Saidi, Spatiotemporal floodplai mapping and prediction using HEC-RAS-GIS tools: case of the Mejerda river, Tunisia, Journal of African Earth Sciences, 142, 2018,44–51.
[18] Hossein, A., Javaheri, N., Daghigh, Y., & Tolooiyan, A. Simulating of Unsteady Flow in Tidal Zones By Using HEC-RAS Model. Strömungssimulation Im Wasserbau (Flow Simulation in Hydraulic Engineering , 32 , 2006,57–65.
[19] Rabies, A. M., Abdul-Kareem, B. M., & Al-Dhamin, A. S.  Seasonal variations of some ecological parameters in Tigris River water at Baghdad Region, Iraq. Journal of Water Resource and Protection, 3,4, 2011,262.
[20] G. W. Brunner, HEC-RAS River Analysis System Hydraulic Reference Manual, Version 4.1, U.S. Army Corps of Engineers, Washington, DC, USA, 2010.
[21] The Ministry of Water Resources.
[22] Hec-Ras, Hydraulic Engineering Center, River Analysis System, User Manual2002.