The downpour on Tuesday morning was caused by a complex low pressure system, known as a "Tasman Sea Special", MetService meteorologist Dom Barry said.
Flooding has occurred along Marine Pde at the intersection with Pacific Rd and near Cygnet St.
Coastal Ward Christchurch city councillor Celeste Donovan said crews are working to remove sand from the outfall pipes.
Donovan said the flooding went down as the pipes were cleared of debris.
Traffic management was also in place at Cygnet St, North New Brighton, due to surface flooding.
MetService has forecasted further rain from Thursday to Friday. Rain warnings could be extended in some areas as a result.
"As the low moves southeastwards across the Motu, we can expect areas such as Marlborough and northern Canterbury to encounter some wet weather from Tuesday, with the rain mainly remaining in the eastern Te Ika-a-Māui/North Island," Barry said.
Heavy rain and thunderstorm watches were in place for Northland, Auckland and the Coromandel but not Canterbury.
-With RNZ
