The RMS Niagara

Key points

• The RMS Niagara is a wartime wreck in the Hauraki Gulf.
• There is uncertainty about how much oil is on the Niagara wreck, but we do know that oil was lost when it hit a mine in 1940 and then again during subsequent salvage operations in 1941 and 1953. Since then, the wreck has continued to leak small amounts of oil that disperse naturally
• Maritime NZ has undertaken thorough analysis of available data on the Niagara. That data has been collected from various sources, including historical documents and partial surveys by remotely operated vehicles and other tools
• Maritime NZ has made recommendations based on global best practice that more surveying work should be undertaken to inform a risk assessment.
• Noting potential risks and limitations, Maritime NZ has submitted twice to central government for funding to undertake the recommended surveying, but those submissions have not been successful.
• Maritime NZ is not funded to conduct this work.
• Anecdotal evidence and reporting from regional councils suggests the Niagara continues to release oil in small amounts that, to date, have dispersed naturally. These very small amounts could not be effectively recovered by oil spill equipment.
• Maritime NZ leads the national marine oil spill response capability, which includes resources, plans and equipment for potential oil spills in the Hauraki Gulf. We partner with Northland Regional Council and Auckland Council to regularly exercise and test oil spill response plans for the region.

Background

RMS Niagara (the Niagara) is a World War II wreck situated north of the Hauraki Gulf, 37km east of Northport, close to the boundary between Northland and Auckland regional waters. It is 120 metres deep.

In June 1940, the Niagara sailed from Auckland and hit a sea mine(s) laid by an undetected German auxiliary cruiser. The ship sank rapidly. Among the cargo was a United Kingdom-owned secret consignment of 590 gold ingots being taken to the United States as payment for military supplies.

There is uncertainty about how much furnace oil Niagara had on board when it sank. We understand it had capacity to carry up to 4,324 tons. A significant amount of oil was lost when the ship was sunk. In 1941, a salvage operation used explosives to access Niagara’s bullion room to recover 555 gold bars and an unknown but substantial quantity of fuel oil was also released then.

In 1953, a further 30 gold bars were recovered, leaving five bars unrecovered.

Over the years, surface oiling has been observed near the wreck and reported to authorities. The oil, shortly after getting to the surface, appears as a ‘sheen’ – such as when oil on the road or driveways mixes with water. To date, these slow releases have dispersed naturally at sea. There have been no reports of significant releases of oil that have impacted surrounding shorelines.

Environmental concerns

Local communities, Iwi, and other interested parties have expressed concern about the possibilities of a substantial amount of oil leaking from the wreck as its structure deteriorates. This is a possibility that Maritime NZ and other authorities plan for, however, the extent of the risk remains unclear.

There is uncertainty about how much oil remains in the Niagara; an issue further complicated as there are no records Maritime NZ has discovered through its research regarding how much oil was carried on the vessel when it sailed.

While some interested parties have estimated the wreck could still hold up to 1600 tons of oil, this cannot be confirmed. The ship’s bunkers (bunkers are the fuel for a vessel) were potentially in eleven designated fuel tanks and three ballast tanks. But it is unknown if it was fully loaded at the time of sailing, or how much oil was lost when it was sunk, during the gold salvage operations and since then.

We also cannot confirm the state of any oil on board the wreck. An oil’s physical characteristics dictate how mobile it may be (at least some of the oil on Niagara is mobile, as confirmed by the leaks to date). The physical characteristics also influence how the oil will act, if it is released.

The area in the vicinity of the wreck includes the Hauraki Gulf Marine Park, several marine reserves and significant coastlines with important ecology.

Oil spill response capabilities

Maritime NZ leads New Zealand’s national marine oil spill response capability, which includes resources and plans for potential oil spills in the Hauraki Gulf, including from the Niagara. We work in partnership with Northland Regional Council and Auckland Council to regularly exercise and test oil spill response plans for the region and maintain specialised equipment and detailed data about sensitive sites.

The primary aims of any oil spill response are to minimise damage to the marine environment and to ensure that, in the event of a significant oil spill, affected areas recover as quickly as possible. We partner with Massey University to ensure that there is a nationally capable wildlife response function to minimise the impact on wildlife. We also maintain contracts with many partners for specialist support, including aircraft, vessels and personnel.

The primary response plan for an oil spill from the Niagara works in conjunction with Maritime NZ’s National Marine Oil Spill Contingency Plan (NMOSCP). The NMOSCP is supported by detailed documents and templates that inform specific processes for any potential oil spill from the Niagara or any other vessel in the Hauraki Gulf.

Maritime NZ maintains a nationwide network of 400 trained regional responders, and 136 members of the National Response Team who can take leadership or specialist roles during an oil spill response anywhere in the country.

Maritime NZ provides national-level planning and training that is critical to maintaining and developing responders’ capability, irrespective of where the response occurs and what equipment is being used. We use a global network of training providers, to ensure our training reflects good practice.

Exercises are also used to validate training and maintain skills. Each year, Maritime NZ runs approximately 15 training events, which are mainly hands-on training courses, on the water and shorelines. There are also 32 regional exercises per year, and a national exercise every three years.

What has been done

Maritime NZ has a keen awareness of available information on the Niagara. This includes photos and video from technical divers, visual information from privately funded ROV surveys, as well as partial visual surveys by the Royal New Zealand Navy. Maritime NZ has sought advice from interested parties who can provide a long-term view on the wreck’s state of degradation.

Maritime NZ also commissioned research into the potential costs for detailed survey work in preparation for the funding bids.

Maritime NZ has engaged with international experts, particularly the UK Ministry of Defence, which oversee some 5,000 historical shipwrecks, to understand best practice to managing a wreck such as the Niagara.

Based on this work, Maritime NZ has given advice to successive governments that outlines more detailed risk assessment options to inform a more comprehensive oil spill risk profile for the Niagara. Maritime NZ is not currently funded to undertake detailed risk assessment of Niagara. In simple terms, the recommended approach to gain a more detailed appreciation of risk, based on global best practice, includes:

• Stage one: a study of available information about the vessel and the environment surrounding the wreck.
• Stage two: survey activity, consisting of two parts.
• Part One: Visual survey of the wreck using remotely operated vehicles (ROV) to inform its state of degradation. The findings from this non-invasive visual survey contribute to the associated risk assessment.
• Part Two: Use specialist equipment deployed from remote operated vehicles to assess contents of some of the vessel’s bunker spaces, and measurements of hull thickness.

Together, stages one and two can be used to ascertain risk. If the risks are unacceptable, then stage three is an oil removal operation.

Note that while the surveys will provide more information, there are limitations. These are due to the complex nature of the measuring techniques and the orientation of the Niagara (the ship is lying on her side, which limits access to some areas).

We have recommended this three-stage approach to former and current Ministers and requested funding to undertake the recommended surveying. To date, funding has been declined, given other priorities. Maritime NZ does not have any internal budget that can be used to undertake this work. Maritime NZ takes all reports of oil spills seriously and our specialists have visited the site periodically, such as when reports of potential leaks are received. If sightings of surface oiling are reported to us, we make an assessment that includes:

• Confirming that there is an oil spill
• Quantifying the amount of oil spilled
• Determining if the amount is on-going (and if so, the rate of release)

Where oil cannot be confirmed as rising to the surface, Maritime NZ specialists will also attempt to identify the spill source, as there are other sources of oil spills e.g. shipping.

Specialists visited the site in 2019, following reports of surface oiling in the area.

The Royal NZ Navy undertook partial visual surveys in 2021 and 2022. The survey data is one source that informs Maritime NZ of the wreck’s integrity and helps to identify changes in the environmental risk posed by the wreck. However, while this contributes information, the full survey programme is still required. Current naval capabilities cannot undertake the full scope of surveying Maritime NZ has recommended is needed (i.e. Survey Parts One and Two).

If, at any stage, significant amounts of surface oiling were reported, Maritime NZ would respond. For a significant oil spill in the area, it is likely that a Tier 3 marine oil spill response would be initiated.

FAQs

Q: What are the chances of a major oil leak from the Niagara?

It is impossible to determine the volume of oil remaining in the wreck or its condition at the present time. However, Maritime NZ and our partners plan for several possible scenarios.

One scenario is the continuation of what has been happening over past decades: the ongoing gradual loss of small amounts of oil over time that disperse naturally and with minimal impact; or several significant releases as sections of the vessel deteriorate and collapse; or a combination of both.

An additional factor is the age of the oil. As oil ages the volatile lighter components degrade quickly, giving the hydrocarbon smell that has at times been noticed. The remaining oil thickens, stays on the seabed and begins to break down. Some of the oil will have degraded like this but how much is not known.

Q: How do small oil leaks disperse naturally?

Oil spreads quickly on the sea’s surface, resulting in a thin layer of oil. Small amounts of oil will rapidly appear as a ‘sheen’ on the surface, either with a ‘rainbow’ effect or as a ‘silver sheen’. These very thin layers of oil cannot typically be recovered. It is well known that natural processes break down oil. Surface oil is subject to natural processes such as ultraviolet radiation, natural dispersion, evaporation, and biodegradation. The smaller the volume of oil (and the thinner the oil layer) the faster these processes will occur. These types of small oil leaks have been reported on occasions near the Niagara (see timeline). Maritime NZ takes all reports of oil leaks seriously and responds accordingly.

Q: Do these small oil leaks affect the marine environment?

Reports to date indicate that surface oiling has been irregular, and the releases have not been of significant volume. There is no information to suggest that shorelines or flora and fauna have been affected.

There are risks to wildlife with any spill. Potential impacts depend on many factors and variables. Maritime NZ’s expert marine oil spill response unit works closely with a national team of wildlife specialists who are ready and equipped to respond to any oil spill incident that has the potential to impact wildlife.

Q: Is the Niagara being monitored?

Maritime NZ maintains a database of all reported spills. This includes information received from dive enthusiasts, or those with ROVs capturing images and video footage of oil leaking from the actual wreck. It is important to note that these have been ‘wisps’ of oil, not releases of significant volume.

Reports of oil can be lodge with the Northland Regional Council, Auckland Council, or directly to Maritime NZ – the point of contact is the RCCNZ [details].

If sightings of oil are reported to us, we assess the information provided. If the report is of considerable concern, we visit the site and make an assessment. This includes confirming that it is an oil spill, the amount of oil, and whether it is on-going (if it is, we assess the rate of release). We will identify the source of the spill, where possible.

Maritime NZ last visited the site following a report in May 2019.

The Royal NZ Navy undertook partial visual surveys of the wreck in 2021 and 2022, the results of which were provided to Maritime NZ.

As noted elsewhere on this page: these events contribute some information, but a full survey programme is required to inform Maritime NZ of the wreck’s integrity.

Maritime NZ is not funded to monitor the Niagara wreck.

Q: How much oil is on the Niagara?

With the information available, there is no way of knowing how much oil is on board the wreck. The ship had capacity to carry up to 4,324 tons, although it is unknown if it was full when it left New Zealand.

A significant amount of oil was lost when the ship was sunk. A substantial amount was also lost during the first salvage operation to recover gold bars from the cargo. And small amounts have continued to leak and be naturally dispersed slowly in the decades since.

Q: Can work be undertaken to determine how much oil is on board and what the risk of a leak is?

Maritime NZ has engaged with international experts to understand global best practice for managing a wreck such as the Niagara. The recommended approach of surveying the Niagara would inform a risk assessment but is unlikely to provide a complete understanding of how much oil may be on board. The recommended approach is:

• Stage one: a study of available information about the vessel and the environment surrounding the wreck.
• Stage two: survey activity, consisting of two parts.
• Part One: Visual survey of the wreck using remotely operated vehicles (ROV) to inform its state of degradation. The findings from this non-invasive visual survey contribute to the associated risk assessment.
• Part Two: Use specialist equipment deployed from remote operated vehicles to assess contents of some of the vessel’s bunker spaces, and measurements of hull thickness.

Together, stages one and two can be used to ascertain risk. If the risks are unacceptable, then stage three is an oil removal operation.

Note that while the surveys will provide more information, there are distinct limitations. These are due to the complex nature of the measuring techniques and the orientation of the Niagara (the ship is lying on her side, which limits access to some areas).

We have recommended this three-stage approach to former and current Ministers and requested funding to undertake the recommended surveying. To date, funding has been declined, given other priorities. Maritime NZ does not have any internal budget that can be used to undertake this work.

Q: What plans are there in case of a major leakage?

Maritime NZ maintains a specific response plan for the Hauraki Gulf, which is applicable to an oil spill from the Niagara; this plan was updated in 2023.

More broadly, New Zealand has comprehensive plans and capabilities to manage marine oil spills based on international protocols. A large-scale spill would be managed as what is known as a Tier 3 marine oil spill response. Maritime NZ provides Tier 3 response capability; extensive information on these capabilities is available on our website.

Q: Is it possible to remove oil from wrecks such as the Niagara?

It is possible in the right conditions to remove oil from wrecks, and this has been done successfully in other jurisdictions. This is highly specialized work and is a very expensive process that has inherent risks, such as creating an oil spill.

Q: what are the costs for the recommended surveys?

Maritime NZ has not been asked to revise the estimates for these costs – given the time since the last budget bids, made 2018/19, and in 2020/21, and the effects of inflation costs will have increased significantly but no figures are available at this time.