State Highway 29A between Barkes Corner and Oropi Roundabout is expcted to be open in time for peak hour traffic on Tuesday morning with roadworkers set to work through the night.

"Roadworkers are now in the process of rebuilding SH29A in Tauranga after we closed it following the discovery of a hole beneath the road on Friday afternoon," says an NZTA Waka Kotahi spokesperson.

"They'll work through the night so it's open tomorrow morning, in time for peak travel."

The four-metre deep and four-metre wide hole was at least 11 metres long, stretching across the width of the road.

The cavity under State Highway 29A between Barkes Corner and Oropi Roundabout. Photo: NZTA Waka Kotahi.

NZTA say the hole was caused by the failure of a stormwater drain which likely occurred some time ago. Water leaking out eroded the land under the road.

Roadworkers worked around the clock to replace 38 metres of stormwater pipe, which required them digging up the whole road as can be seen in photos.

They’ve now backfilled the trench and are rebuilding the road.

Roadworkers at work on State Highway 29A on Monday. Photo: NZTA Waka Kotahi.

"You won’t be driving over the final asphalt seal when the road reopens tomorrow morning, but the road will be surfaced," says an NZTA spokesperson.

"We’ll have traffic management in place and a reduced speed limit of 50km per hour.

"Thanks to those who avoided travelling this morning if they could—we wanted anyone who absolutely had to travel to could get through without extended delays.

"We really appreciate your patience while roadworkers completed these urgent repairs, and want to give a big thanks to the workers for their quick work to get the road back open!"