There have been huge delays for those heading into the Waterview Tunnel - northbound - after at least three incidents early this morning.
Emergency services were called to a crash just before the Maioro St off-ramp on State Highway 20, Southwestern Motorway, heading towards the city just after 7am.
An alert was issued at 7.25am via the Waka Kotahi NZ Transport Agency Twitter page.
"A crash is blocking the left lane, northbound, prior to Maioro St off-ramp. Pass with care (and) expect delays."
Traffic cameras showed at least one vehicle on the left side of the road and a number of people standing nearby.
By 7.30am, road authorities said two northbound lanes in the tunnel had been temporarily blocked as medical assistance and vehicle recovery services arrive at the scene.
A short time later, authorities said the breakdown had been cleared, but that a subsequent crash was blocking the left lane - inside the tunnel - again.
"Expect continuing delays," they said.
Yet another crash was reported just before the Maioro St off-ramp at 8.40am.
The crash was blocking the right northbound lane for some time, before authorities said it had been cleared by 9.10am.
Earlier, just after 6.30am, NZTA alerted motorists using the northbound tunnel to merge right with care and to expect delays, due to a breakdown blocking the left lane.
Rain is also causing surface flooding in some parts of the motorway network and people are being urged - via overhead motorway signs - of the need to drive to the conditions.
Takapuna crash causing delays 'in all directions'
A crash at the intersection of Taharoto Rd and Anzac St and Fred Thomas Drive, in Takapuna, has also caused traffic delays "in all directions" early on, authorities say.
An alert was issued online at 7.40am urging motorists to avoid the route or to allow for extra travel time. The incident was cleared just after 8.30am.
That crash came just before another was reported on SH1, on the Northern Motorway, at 8.30am.
A crash was partly-blocking either side of the southbound lanes after the Silverdale on-ramp and people heading into the city were told to expect delays.
The area was cleared by 9.15am but motorists were told to allow for extra travel time.
Southern Motorway delays
On the other side of the motorway network, emergency services were called to a collision just after the Takanini off-ramp on the Southern Motorway.
The crash, alerted at 7.45am, was blocking the left northbound lane on the motorway just after the Alfriston Rd overbridge.
The incident was cleared by 8.30am but delays were reported for citybound motorists from as far back as Drury.