Motorists north of Auckland are having to navigate narrow rural roads for 33km following a crash that is blocking State Highway 1 north of Wellsford, with one driver saying it is “chaos”.

A truck rolled north at Topuni around 10.15am, blocking lanes in both directions near the intersections with Schiska and Otioro Rds.

In an update shortly after 12pm, New Zealand Transport Agency Waka Kotahi said vehicle recovery and clean-up was “expected to take some time today”.

The detour requires both northbound and southbound commuters to travel through Mangawhai, adding an extra 33km to their journeys.

One motorist travelling north who encountered the detour said it was “f***ing chaos” on the narrow, unsealed road.

”The road is one car wide,” they said.

“There’s hundreds of people trying to traverse Northland’s new state highway.

”I’d advise anyone coming through not to use it if at all possible.”

Video shared with the Herald shows commuters at a standstill, while trucks and vehicles towing trailers inch down a narrow gravel road along the detour.

A police spokesperson said there were currently no reports of any injuries from the scene.

Motorists were advised that diversions would be in place for both northbound and southbound traffic.

“Expect delays on your travels while the scene is cleared,” said the spokesperson.