Patillas Dam Failure Analysis Modeling Using HEC-HMS, HEC-RAS Simulation Programs and Geographic Information System

Abstract

Carlos Negron Alfonso, Master’s in Civil Engineering Candidate, in cooperation with the Final Project conducted a Dam Breach Analysis for the Patillas Dam. This hydrologic and hydraulic study will assess the potential hazar to human life and property downstream from the Patillas Dam, associated with the hypothetical failures of the dam for the probable maximum floods resulting from a 6 and 24-hour duration probable maximum precipitation and for the 100- year floods resulting from a 6 and 24-hour duration 100-year rainfall. The study consists of the determination of outflow hydrographs from Patillas Dam under non-failure and failure conditions corresponding to the probable maximum flood, 100-year flood, and non-flood condition (sunny day), and their subsequent routing through the lower reach of the Rio Grande de Patillas. To perform the hydraulic analysis, the U.S. Army Corps of Engineers HEC-RAS program was utilized to simulate and analyze the various flood conditions produced by breaching the Patillas Dam. The dam break analysis was performed using the unsteady flow module available in HEC-RAS. Key Terms - Geographical Information System, HEC-HMS, HEC-RAS and HEC-GeoRAS