Images from the state Department of Water Resources show round-the-clock work the week of March 11-17, 2017 at Oroville Dam. A giant fracture developed in Oroville Dam’s main spillway during a heavy storm earlier this year. Five days later, water flowed over the dam’s emergency spillway for the first time, nearly causing the hillside below to fail. Approximately 188,000 downstream residents were evacuated for two days.