A truck has crashed on Auckland’s Southwestern Motorway this afternoon, creating delays for motorists.

The crash happened in a southbound lane of State Highway 20 ahead of the Puhinui Rd off-ramp about 2.15pm, the New Zealand Transport Agency (NZTA) said.

A truck carrying some 10 tonnes of dirt rolled over a barrier on the Southwestern Motorway. Photo / Anupinder Singh Sidhu

Fire and Emergency NZ told the Herald a truck carrying 10 tonnes of dirt had rolled over a barrier. Crews were called to the scene at 1.53pm, a spokesman said.

Three fire trucks were scrambled to the scene, and firefighters have been assisting police, he said.

Traffic is backed up after a crash on Auckland's Southwestern Motorway. Photo / Google

The crash blocked the left southbound lane before Puhinui Rd, however all southbound lanes were temporarily opened a short time later.

“Please allow additional time for delays in the area to ease, expect queues in both directions,” the NZTA posted to X.

Congestion had backed up 7.5 kilometres north to Māngere Bridge as of 2.45pm, reaching back to the airport interchange onto State Highway 20A, live traffic data from Google showed.

One person was taken to hospital with moderate injuries, a police spokeswoman said.

“No other vehicles were involved, and the road is not blocked,” she said.

The crash happened in a southbound lane of State Highway 20 ahead of the Puhinui Rd off-ramp. Photo / Anupinder Singh Sidhu