The HMS Cassandra: A Hidden Environmental Threat
In December 1918, the HMS Cassandra was on a mission to support Estonian efforts to break away from Bolshevik rule at the end of World War I. As it made its way towards Tallinn, the ship encountered a mine and sank off the island of Saaremaa. Of the 400 crew members aboard, most survived, but 11 were lost with the cruiser.
The wreck of the Royal Navy ship lay hidden at around 100 meters deep until its discovery in 2010. Inside the remains, a hidden environmental threat was found in the form of oil. Matt Skelhorn, currently surveying the site, describes the wreck as “exceptionally preserved,” noting that it is in better condition than many other wrecks encountered in British waters. This preservation presents an interesting challenge for those tasked with managing the potential risks posed by the ship.
The wreck is decaying slowly, which means it is unlikely to collapse or cause a catastrophic oil spill in the near future. However, the good condition of the ship also suggests that large amounts of oil may still be onboard. The HMS Cassandra is already leaking small quantities, and eventually, what remains will be released into the environment.
Harriet Rushton, the wreck environmental manager at the UK Ministry of Defence’s Salvage and Marine Operations team (SALMO), explains that the aim of the current survey is to assess the wreck’s condition and determine how to manage it moving forward. This information will help shape proactive management plans to prevent leaks and avoid the need for cleanup after a major spill.
A Global Problem with Local Consequences
The HMS Cassandra is just one example of a broader issue involving potentially polluting wrecks (PPWs). These wrecks contain fuel or cargo that can cause environmental damage if they leak or release their contents. They are scattered across the world, from the Baltic Sea to the South Asia-Pacific, and some are already leaking, threatening marine ecosystems, fisheries, and nearby communities.
Experts estimate that there are about 8,500 PPWs beneath the ocean, most dating back to World War I and II. However, the actual number is likely much higher due to limited data. After 80 to 110 years, these wrecks are becoming increasingly unstable, according to Project Tangaroa, a global community of experts working to address this toxic legacy of conflict.
At the UN Oceans Conference (UNOC3) earlier this month, Project Tangaroa issued an urgent call to action, emphasizing the need for international collaboration to tackle this growing problem. The organization has already played a key role in connecting the UK and Estonian governments to address the HMS Cassandra and hopes to do the same for other nations.
Climate Change and the Acceleration of Risk
There is another layer to the urgency surrounding PPWs, exacerbated by human activity. These wrecks have been gradually corroding over decades, but the rate of deterioration has started to accelerate. Rising ocean temperatures and increased acidity—both direct consequences of climate change—are speeding up the breakdown of these structures. Extreme weather events, such as typhoons and storm surges, are also becoming more frequent and intense, further stressing these weakened wrecks.
Lydia Woolley, Programme Manager at the Lloyd’s Register Foundation, explains that climate-driven changes, combined with growing industrialization, bottom trawling, and emerging threats like deep-sea mining, significantly heighten the risks associated with PPWs. Human activity is shortening the already precarious timeline for these ticking environmental time bombs.
The Need for Data and International Collaboration
To act before a catastrophe occurs, experts and governments need detailed data on where wrecks lie, their condition, and the pollutants they contain. However, crucial information is often patchy and inaccessible. The UK MOD’s SALMO team has been closely involved with Project Tangaroa since its inception, highlighting the importance of better data sharing.
Matt Skelhorn, Head of the UK MOD Wreck Management Programme at DE&S SALMO, notes that while there is a good idea of how many ships sank in World Wars I and II and their approximate locations, many wrecks remain undiscovered, especially in deeper waters and remote areas. Even in regularly surveyed regions, many wrecks have been misidentified, making it difficult to assess potential risks.
Wrecks can have multiple roles beyond being environmental hazards. They can serve as habitats for marine life, support local fisheries, and even be sites of cultural heritage. Some are considered war graves, adding another layer of complexity to their management.
Navigating Legal Loopholes and Responsibilities
Determining who is responsible for cleaning up these wrecks is a complex issue. Lydia Woolley points out that there is a “kind of loophole” in the legal framework governing oil spill management. Current arrangements typically focus on contemporary incidents involving privately owned vessels, not the challenges posed by PPWs.
While some protocols exist, such as the 2007 International Maritime Organisation’s Wreck Removal Convention and the International Oil Pollution Compensation Fund, these only apply to privately-owned ships and not necessarily to state-owned wrecks. Sovereign immunity also complicates matters, as flag states may not be legally compelled to act without consent.
This lack of clear responsibility leaves coastal countries vulnerable, as they often depend on flag states to react on a case-by-case basis. Without an established international legal framework, addressing the risks posed by PPWs remains challenging.
Seven Key Calls to Action
At UNOC3, Project Tangaroa published ‘The Malta Manifesto,’ outlining seven key calls to action aimed at encouraging governments to act decisively. The manifesto advocates for a precautionary approach and global cooperation on long-term solutions, emphasizing the need for financing, standards, regional planning, innovation, training, and data sharing.
One of the key recommendations is the establishment of an international PPW Finance Task Force to drive cooperation and innovative financing solutions. Woolley concludes that while the knowledge to manage these risks exists, the resources needed to implement solutions at scale are lacking.
The message is one of urgent encouragement, urging governments, industry, researchers, and civil society to work together to address this growing environmental threat before it reaches a breaking point.
Post a Comment