Raised motorway no match for climate's fury

A section of Auckland motorway is expected to be raised again after it was blocked by flooding in the latest storm.

Hundreds of millions has been spent since 2014 raising the Northwestern Motorway by 1.5 metres.

But parts of it, and Tamaki Dr in Mission Bay, were closed after the king tide and storm surges caused them to flood in the recent North Island storm.

Patrick Reynolds of transport lobby group Greater Auckland believes it won't be long before climate changes forces us to do it again.

"There is some irony in us spending fortunes lifting these motorways and widening them and not providing people with alternatives, which incentivises more driving, creates more greenhouse gases and leads to more sea level rises."

Mr Reynolds hopes a rapid transit line for public transport is included when the road is next upgraded. Failure to do so would highlight a lack of forward-planning.

"These events are happening more frequently, and it seems entirely plausible they are linked to sea level rise and climate change," he told Newshub.

"We have through NZTA spent hundreds of millions of dollars raising the height of the Northwestern Motorway and widening it. Clearly we're going to have to do this again."

The Northern Motorway north of the Harbour Bridge was also closed on Friday due to flooding.