Marine warning buoy washes up on Wellington shore

Planes flying into Wellington Airport or boats sailing in the waters around site were not put in any risk after a huge warning buoy washed up on shore this morning, the airport says.

The marine warning buoy - designed to alert tall vessels of low-flying aircraft in the approach to Wellington International Airport - came loose in large swells in Lyall Bay this morning and ripped from its moorings.

It has since washed up on shore, and an investigation into how it came free will be launched.

The buoy was one of two markers Wellington Airport has stationed in Lyall Bay to warn tall vessels not to enter the area, an airport spokesman said.

"So what happened this morning was one of the marked buoys came loose with the size of the swell and drifted into Lyall Bay," he said.

"It remained visible and upright at all times, that's the way it's designed, and it was monitored and slowly drifted into shore where we had it salvaged and taken away to be inspected."

An investigation into how it was dislodged from its anchor will take place, he said.

"It was designed for bigger swells than this, and it's been used in many places, so we would need to investigate what particular thing went wrong."

The 600kg buoy is lifted off Lyall Bay beach. Photo / NZ Herald

However, no boats or planes were at any risk because of the roaming buoy.

"[There was] no disruption or anything like that. It's merely a marker area and so it wouldn't have any effect on flights," the airport spokesman said.

"It is a clearway safety area but in reality there's no yachts of that height [that] would be in that area anyway, just because it's so close to the rocks and the runway.

"But it's something that we have decided to do for aviation purposes just as an extra clearway safety measure, but it is highly unlikely that a vessel of that height would be in that area anyway, especially with the swell this large."

The buoy would be assessed, and then likely put back out to sea with any recommended improvements or fixes, he said.

"In the meantime we will just leave it vacant, because there's another buoy out there anyway."