2021-07-29 05:05:18 GMT2021-07-29 13:05:18(Beijing Time) Xinhua English WELLINGTON, July 29 (Xinhua) -- Flood flows on South Island's Buller River this month were the largest of any river in New Zealand in almost 100 years, the National Institute of Water and Atmospheric Research (NIWA) announced on Thursday. NIWA hydrodynamics scientist Richard Measures said records show even larger flooding of the Buller River in 1926. "It's not the largest river in New Zealand but it does experience the biggest flood flows. The flood levels through the Buller gorge are incredible," he said. NIWA environmental monitoring technician Mike O'Driscoll used a radar gun from the Westport and Orowaiti bridges to measure the speed of the Buller River at its surface on July 17.