Open dam at Lake Pukaki feeding river with fresh glacial meltwater

aerial footage spilling high water level heavy rains turquoise blue pukaki river twizel canterbury new zealand aerial view drone footage natural disaster flooding dam overflow extreme weather hydroelectric power environmental impact river overflow emergency response flood control hydrology infrastructure engineering hydroelectricity rainwater natural resource dam safety water conservation hydroelectric dam river management water crisis weather patterns climate change environmental resilience water infrastructure river systems natural hazard dam infrastructure discharge flow control resource management waterfall spectacular stunning drone orbit nature mountain range mt cook