The discovery of a sunken launch at its mooring in Tauranga harbour has prompted Bay of Plenty Regional Council to remind boat owners to check their moorings.

"With the current bad weather it's important for you to check on your boats and their bilge pumps," says a council spokesperson.

"Unfortunately this launch sank quite quickly in Tauranga harbour.

"We're investigating the cause and working to recover the vessel but the current weather is making this challenging. Stay safe out there!"

The council posted the reminder to their Facebook page on Friday.

In 2022 Bay of Plenty Regional Council's Harbourmaster team said it had had its busiest winter in recent memory assisting with the salvage of a number of boats in Tauranga Harbour.

The last week in July 2022 alone saw four vessels needing assistance from the Harbourmaster team after heavy rain and strong winds.

One vessel was partly submerged needing water to be pumped out and the boat removed from the Harbour, while another sunk to the seafloor. Two other vessels broke free from their mooring and anchor.

A boat that sank in July 2022 in Tauranga harbour. Photo: BOP Regional Council.

The salvage operations that follow these are a stark reminder for boat owners to check their vessels on moorings.

With cloudy days, owners of vessels relying on solar should also be checking battery levels to ensure automatic bilge pumps are operating.

It is essential that boat owners check on their vessels regularly to catch any issues early.

The July 2022 incidents were caused by a mooring line chafing/wearing on a sharp edge, and boats slowly taking on rainwater and the bilge pump failing. These could have been easily prevented with some regular maintenance checks.

A boat that grounded in July 2022 in Tauranga harbour. Photo: BOP Regional Council.

Salvaging a boat that has sunk on its mooring can be a costly exercise for the owner with the bill coming in between $10-$15,000 per day for a commercial dive team and suitable barge.

The boat owner is liable for these costs and dependent on the size of the boat and how long it takes to get it out of the water it can cost much more.

In some cases the boat may be disposed of and destroyed by the Regional Council under the authority of the Maritime Transport Act 1994 with the boat owner liable for all costs incurred.

Boats moored in Tauranga harbour. Photo: BOP Regional Council.

A mooring refers to an approved structure to which a vessel may be secured. In the Bay of Plenty there are more than 490 designated swing moorings spread across Tauranga, Whakatāne and Ōhiwa harbours. These areas are identified in the Navigation Safety Bylaw.

To read more about Bay of Plenty moorings and boating in the bay, click here www.boprc.govt.nz/living-in-the-bay/boating-in-the-bay/moorings