State Highway 2 north of Wellington has reopened after earlier flooding.
The left southbound lane was blocked before 7am on Friday near the Petone overbridge.
Rush-hour traffic was being directed into the right-hand lane but both lanes opened after 9am, after the flooding receded.
However, the NZ Transport Agency warned drivers to expect on-going delays until queued traffic clears.
FINAL UPDATE 9:25AM
— NZ Transport Agency Waka Kotahi - Wellington (@nztawgtn) November 14, 2024
Surface flooding has receded and all lanes are now OPEN. Please continue to expect delays while congestion eases. ^AP https://t.co/83NRIjdEe9
The flooding came amid a wet day for much of the country.
Heavy rain warnings and watches were in place for parts of Westland, Tasman, Tararua, Canterbury Lakes, northern Taranaki and Bay of Plenty.
Wellington was forecast to have periods of rain including "possibly heavy before dawn", according to MetService.
While the rain would ease in the region on Friday afternoon, it was expected to return at night.
Sewage outfall into Wellington waterways
Meanwhile, sewage has been discharged into Wellington's waterways after heavy rain overnight.
Wellington Water said high rainfall within the catchment has led to higher inflows at its processing plants.
Shortly before 3am on Friday, untreated sewage was discharged into the ocean at Tarakena Bay from the Moa Point Wastewater Treatment Plant.
Then, at 6am, treated wastewater was released into the Waiwhetū Stream in Lower Hutt from the Seaview Plant.
Wellington Water said it was arranging coastal samplings and people should stay out of the water.
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