PHOTO: LINDA ROBERTSON
NZ Transport Agency journey manager Peter Brown said the culvert under State Highway88, at Tekapo St, Ravensbourne, had started to slump in recent days.
Yesterday it slumped further, prompting the closure of the east lane.
"The site will be down to one lane, controlled by signals, for several days whilst full investigation and repairs are completed" he said.
Delays of up to five minutes were expected.
