Ricardo Zubieta Barragan,Julio Quijano,Karen Latinez,Alejandra G. Martínez,Percy Guillermo, Instituto Geofisico del Peru, Lima, ricardo.zubieta@igp.gob.pe
The Mantaro River valley is located between the western and eastern cordilleras of the Peruvian central Andes, and is a major agricultural region. The valley is constantly affected by floods associated with heavy precipitation, which cause extensive crop losses. The objective of this study is to assess the floodplain hazard with maximum discharges and at different return periods, using the hydraulic model HECRAS (Hydrological Engineering Center - River Analysis System). The methodology performed includes frequency analysis of discharges and the construction of a detailed digital terrain model (DTM) by stereoscopic methods. Discharge data obtained from the frequency analysis, the DTM and the river geometry based on Quickbird and GeoEye satellite imagery, were used for modeling. The results have allowed us to analyze the floodplain with return period of 1, 10, 25, 50, 100 years, with high accuracy, attributed primarily to the digital terrain model. The results provide the technical basis for an early warning system in the Mantaro Valley. Important information was provided by the valley residents about the flood zones for perform prevention and mitigation purposes.
Keywords: Flood, Hazard, remote sensing