A car rolled on Salisbury St, near the intersection with Durham St in Christchurch, early Thursday.

A driver had to be cut from her vehicle after she crashed and rolled on Salisbury St, near the junction with Durham St.

Salisbury St was closed between Colombo and Durham streets for a short time after the crash at about 6.45am on Thursday. Both lanes of the road had reopened by 8am.

"We received multiple calls of a car on its side on Salisbury St; one caller said the driver was trapped but conscious and breathing," a police spokesman said.

The driver was trapped until fire crew cut them from the vehicle.

Firefighters used cutting equipment to extract the driver who was taken to Christchurch Hospital with moderate injuries.

A Salisbury St resident, who did not want to be named, said she heard the smash and raced to help. She had lived on the street for just over a year and in that time had seen several collisions.

She said the crashes could be due to a combination of factors.

"Usually, [the crashes happen] when cars try to turn, or because people are speeding. It's just out of the 30km/ph zone and two one-way streets meet.

"To be perfectly honest, I think it's just people not being careful."

In 2015, two people died and another was critically injured after a van drove the wrong down Salisbury street^[1] and through a red light, colliding with a car.

Their families lobbied for improvements to Christchurch's one-way streets, which prompted a petition on Change.org^[2] calling on the Christchurch City Council to fit flashing lights to the back of one-way intersection traffic lights.

Heavy fog in the city prompted a warning from the Christchurch Transport Operations Centre early on Thursday.

But the Salisbury St resident did not think visibility was a factor in the crash as the fog was not heavy until after 7am.

It had lifted from the city by 8am.

 - Stuff