Wellington’s harbourmaster has issued an ultimatum to the owner of a leaking yacht after marina staff spent six months pumping water out of the vessel to prevent it from sinking.

Concerns over its seaworthiness come after a World War II-era ship painted with hundreds of penguins sank in Wellington harbour last year when one of four pumps keeping it afloat was overwhelmed with water.

The 10m classic yacht known as Shamrock is currently without a mast and berthed at Evans Bay Marina.

Wellington Regional Harbourmaster Grant Nalder said the marina has expressed concerns about the state of the vessel and staff were pumping water out of it every few days to counteract what appeared to be a leaking hull.

 “It’s in need of care and unfortunately with some older boats they can get to the stage where the amount of attention they need is in excess of the value of the boat.”

Requests for the owner to rectify the issue have been unsuccessful after progress stalled. The owner told the marina they did not want to comment on the situation, Nalder said.

Nalder has issued a formal direction over the yacht on the grounds it’s a risk to maritime safety.

He said the vessel needed to be removed from the water by April 21 for inspection and then either repaired or disposed of.

 “If the vessel is not removed or acceptable arrangement for removal made by this time, the vessel may be removed from the water and any resulting costs may be recovered from the owner,” Nalder said.

Shamrock was built by Ernie Lane in Picton in about 1927. Photo / Wellington Classic Yacht Trust

The direction was issued a week ago, but the boat remains at the marina.

Nalder said it was much easier to deal with the yacht while it was still afloat.

In general, he estimated the cost to dispose of a vessel could increase from $4000 to $15,000 if it was underwater.

Evans Bay Marina supervisor Tessa Sievers said they have been regularly using a portable pump to remove water from the vessel for six months.

“The main risks are that if the vessel sinks it would become a hazard to other boats and cause environmental damage in the marina and beyond. It’s an expensive and disruptive process to lift a sunken vessel out of the water – we’d much rather that we don’t get to the situation where the vessel sinks.”

The Wellington Classic Yacht Trust said Shamrock was built by Ernie Lane in Picton in about 1927, and was noted as a good safe boat in big seas and strong winds.

The last a spokesman for the trust had heard of the vessel was that it was for sale on Trade Me in 2020, just before the lockdown, in a poor condition at a giveaway price.

Nalder said he also believed the yacht had been listed on Trade Me recently.

Last year a World War II-era ship known as Sealion sank in Wellington Harbour after previously classified as “non-seaworthy”.

The World War II-era ship that sank in Wellington harbour last year. Photo / Supplied

One of the four pumps it was relying on to keep it afloat became overwhelmed and water flooded in the back of the boat, the stern, and near the engine room, before the ship tilted and sank.

Nalder said the Sealion was cut into two pieces and pulled out of the water at the Hutt River mouth. The council was working with its insurance company on options for the recovery of those costs, he said.

There were several vessels across the region in a state of disrepair, he said.

“There is no such thing as a cheap boat, you either pay now or you pay later.”