A case study for updating design storm rainfall hyetographs for Houston Public Works

摘要

A project has been completed for the Houston Public Works (formerly City of Houston Department of Public Works and Engineering) that analyzes historical rainfall data including recent extreme events. The aim of this project is to develop a representative design storm based on rainfall hyetographs recorded by rain gauges, and analysis of storm motion and areal distribution, from archival radar data. In support of this study data retrieval, assembly, and analysis of rain gauge and archival radar data was performed. As a result, a dynamic design storm was developed with updated hyetograph temporal distribution. This updated design storm is being considered for 1) capacity assessment and 2) planning of sanitary sewers affected by rainfall-derived inflow and infiltration (RDII). Analysis extended to 2016 with updates included for Hurricane Harvey August 25 to 29, 2017. A representative design storm based on local rainfall can result in more efficient planning and design of capital improvement projects for sanitary sewers experiencing RDII and helps understand the unusual nature of extreme storm events and their impact on the sanitary sewer system.