Page - 24 - in Book of Full Papers - Symposium Hydro Engineering

COMMISSION INTERNATIONALE DES GRANDS BARRAGES ------- VINGT TROISIÈME CONGRÈS DES GRANDS BARRAGES L’Autriche, juillet 2018 ------- OROVILLE DAM SPILLWAY INCIDENT — WARNINGS AND THE HUMAN RESPONSE Jason Needham Consequence Specialist, United States Army Corps of Engineers Risk Management Center Dr. John Sorensen Distinguished Researcher, Retired, Oak Ridge National Laboratory Dr. Dennis Mileti Professor Emeritus, University of Colorado, Boulder Matthew Murray California Department of Water Resources UNITED STATES OF AMERICA 1. INTRODUCTION Oroville Dam is located on the Feather River in northern California (USA). At 234.7 m (770-ft) tall, this earth embankment is the tallest dam in the United States. With its 4.3 billion m3 (3.5 million acre-feet) of storage, Lake Oroville is the second largest reservoir in California, supplying water to cities as far south as Los Angeles. The Oroville Dam, reservoir (Lake Oroville), and hydropower plant facility is the flagship of the State Water Project (SWP), which is owned and operated by the State of California, Department of Water Resources (DWR). The 2016-2017 Winter Storms brought record breaking precipitation to the Northern California Sierra mountains including the Feather River watershed. On February 7, 2017, the Oroville Dam’s 54.5 m (179-ft) wide Flood Control Outlet (FCO) Spillway chute (Fig. 1) was releasing water to control the Lake Oroville 24