An overview of the impact of Hurricane Harvey on chemical and process facilities in Texas

Category 4 Hurricane Harvey with maximum sustained winds of approximately 212 km/h and more than 1000 mm of rainfall reached the densely populated Houston area, Texas, resulting in unprecedented flooding and damage to the onshore industrial facilities. In order to analyze the impact of flood, rainfall, and wind on onshore chemical and process facilities during Harvey, an investigation of the damage suffered by onshore chemical and process facilities is conducted using government incident databases. Based on the locations of the damaged equipment, the corresponding maximum flood depth, accumulated rainfall, and wind speed were identified through online GIS interactive maps and the software ArcGIS. In line with the previous studies in the field of natural-technological accidents (Natechs), atmospheric storage tanks were identified as the most vulnerable type of process equipment. Flooding and unprecedented rainfall were identified as the main causes of Natechs during hurricane Harvey. Further, compared to the common failure modes observed during previous hurricanes, the roof sinking of tanks with floating roofs due to excessive accumulated rainfall was identified as a serious failure mode during hurricane Harvey. In order to reduce the risk of roof sinking in future hurricanes, the design standards of floating-roof storage tanks need to be updated to enable withstanding excessive rainfalls in the future.