Colorful fireworks light up San Diego Bay during a previous Big Bay Boom event. (Photo courtesy of bigbayboom.com.) SAN DIEGO (KUSI) – The popular San Diego Big Bay Boom fireworks event, described by local port officials as the state’s largest, will return on July 4, the Port of San Diego announced Tuesday. The 20-minute fireworks extravaganza will start at 9 p.m., with advanced pyrotechnics launched simultaneously from four bridges around San Diego Bay, Port officials said. The event was canceled last year due to the COVID-19 pandemic. Instead, Fox 5 San Diego aired a television special highlighting the best moments of past Big Bay Boom shows.