Traffic is backed up for about 9km after an incident near Spaghetti Junction.
The incident happened about 12pm at the Southern Motorway link to the Northwestern Motorway, westbound.
Drivers were asked to avoid the area and consider using an alternative route.
UPDATE 1:25PM The SH1 link to SH16 westbound has RE-OPENED following a earlier incident. Traffic remains heavy northbound between Penrose and the SH1 Link to SH16 westbound. Consider delaying your journey if possible, or be prepared for delays. ^MF https://t.co/uavA2uoiru
— Waka Kotahi NZTA Auckland & Northland (@WakaKotahiAkNth) February 12, 2020
The New Zealand Transport Agency said at 1.25pm theroad had reopened but traffic remained heavy between Penrose and the State Highway 1 link - a journey of about 9km.
"Consider delaying your journey if possible, or be prepared for delays."
Police have cordoned off a section of footpath on Alex Evans Road, above the motorway, in relation to the incident.
UPDATE 12:50PM The SH1 link to SH16 westbound remains CLOSED. Northbound traffic continue onto SH1 north to Nelson St then turn right onto Cook St, then right onto Hobson St then follow signs for SH16 westbound. ^MF https://t.co/uavA2uoiru
— Waka Kotahi NZTA Auckland & Northland (@WakaKotahiAkNth) February 11, 2020
