Hurricane Harvey Precipitation Totals and Probable Maximum Precipitation Estimates along the U.S. Gulf Coast

In August 2017 Hurricane Harvey made landfall on the Texas coast. Several locations near the coast reported precipitation total depths in excess of 50 inches, the largest ever recorded rainfall depth in the U.S. from a single storm. Probable maximum precipitation (PMP) estimates using the procedures outlined in National Oceanic and Atmospheric Administration (NOAA) Hyrdrometeorological Reports (HMRs) have been used to determine design basis flooding events for nuclear power plants, dams, and other risk significant facilities throughout the United States. This paper investigates precipitation depths at several locations in southeastern Texas during Hurricane Harvey and compares them with PMP estimates from the NOAA HMRs at existing nuclear power plant locations along the U.S. Gulf Coast. The results of this comparison indicate that Hurricane Harvey precipitation depths, although are higher than the depths previously recorded are, nonetheless, lower than PMP depths used to determine design basis flooding at the U.S. nuclear power plants.