Seawall just north of Ohau Point.

The last of more than 7,500 seawall blocks just north of Ohau Point along the Kaikoura coast have been installed.

NZ Transport Agency earthquake recovery manager Tim Crow says this is a significant milestone for the recovery work in what was one of the most damaged areas in the November 2016 earthquake.

“We‘re pleased work has progressed so much on these structures, and it‘s down to the efforts of crew who have been working hard to get the job done. All the seawalls have now been completed just in time for winter,” he says.

“Seawalls offer long term sustainable protection to the road and rail transport corridor from the coastal elements and seismic activity.”

In order to reopen the road for Christmas, the seawalls had temporarily been built at a lower height and since then, work has been underway to build them up for long-term resilience.

To prevent significant traffic interruptions, some activities could only be done at night. This involved importing large volumes of construction material along with the removal of slip material.

When SH1 was opened to traffic by day, the seawalls could only be backfilled at night. Night crews have raised the height of the road at Ohau Point by five metres since Christmas, and around 150,000 cubic metres of backfill has been placed behind the seawalls.

Crow says completing the seawalls was a momentous occasion for the crew, particularly as some team members who had laid the very first foundations also helped place the final blocks.