This research aims to estimate flood areas in agricultural and urban zones located in the lower part of the Tumbes River in Peru, as well as assess the performance of some structural measures to reduce the flood risk. To this end, the FLO-2D two-dimensional hydraulic routing model is used to simulate the spread of flooding along the river reach from the El Tigre control station to the Pacific Ocean (40 km). The analysis is performed for a 100-year flood which is approximately similar to the peak historical flow that occurred in 1998 during El Niño Phenomenon. The methodology includes the LIDAR topography analysis, the assessment and set up of the input flood hydrograph and lateral inflows as an upstream boundary condition, the tidal downstream boundary condition, the calibration of the model using water levels recorded on the Tumbes bridge; as well as a remote sensing approach to validate the flood extension was used. Likewise, land use and coverage maps were used to estimate the spatially variable roughness coefficient for the floodplain. The effect of two flood control dams and levees were simulated and evaluated. The Flo 2D model show a good agreement with historical levels and flood areas of March 2017. In addition, the results indicate that the most of areas of the Tumbes River are within the medium to high hazard zones. However, under the scenario of flood control dams the high flood hazard areas could be reduced by more than 75% approximately.