Silent Doom Beneath: WWI and WWII Warships Are Hidden Pollutant Bombs in Our Oceans
Silent Dangers Lurking Beneath the Waves
When Ancient Warships Corrode
Ships from past conflicts, now rusting unseen on the ocean floor, are becoming silent hazards. Their decaying hulls release toxic substances that threaten marine ecosystems and, ultimately, human health.
- Heavy Metals: Iron, copper, and lead residues seep into surrounding waters.
- Chemical Ammunition: Explosives and propellants break down, releasing carcinogenic compounds.
- Oil Leaks: Residual fuels spread, smothering coral reefs and disrupting food chains.
Why This Threat Is Often Missed
Because these vessels lie far below the surface, their impact is not immediately visible. Yet, as the structures deteriorate, they slowly disperse pollutants that accumulate in the sediment and migrate up the food chain. This invisible spread can harm fish, birds, and even people who rely on marine resources.
Urgent Actions Needed
Scientists and policymakers must prioritize:
Lost Royal Navy Cruiser HMS Cassandra Rediscovered Near Saaremaa
In early 1919, the cruiser HMS Cassandra was on a mission to aid Estonian forces in their fight against Bolshevik control. While navigating the waters off Saaremaa, the vessel struck a mine and eventually disappeared beneath the surface, leaving a tragic loss of 11 crew members while the rest of the 400 survived.
Wreck Unearthed Decades Later
The wreck, resting about 100 metres below sea level, remained hidden until a survey in 2010 brought it to light. Recent investigations suggest the wreck houses a potential environmental issue: residual oil that could eventually leak into the surrounding marine ecosystem.
Expert Opinions
- Matt Skelhorn, aboard the research vessel that examined the wreck, describes the ship as “exceptionally preserved” compared to similar findings in the Baltic Sea.
- Harriet Rushton of DEFENCE Equipment and Support notes that the slow decay of the wreck means a catastrophic spill is unlikely in the short term, yet the well‑preserved structure may cradle substantial oil reserves.
- Despite the current low leakage rate, the continuing presence of oil onboard necessitates a careful and informed management plan moving forward.
Future Considerations
According to specialists, the ongoing survey will establish the exact condition of the wreck and guide future measures to mitigate potential environmental risks. The aim remains to keep the sharp—yet historical—castle under safe stewardship, ensuring that it does not pose a harmful threat to the Baltic marine environment.
A toxic remnant of 20th century conflicts
Final Survey of HMS Cassandra Wreck Sets a New Standard for Prevention
The crew that conducted the detailed examination of the HMS Cassandra wreck seeks to translate its findings into a forward‑looking risk‑management strategy. By collaborating with Estonian authorities, they aim to produce a proactive plan that stops leaks before they occur and eliminates the need for massive clean‑up operations.
Key Objectives of the Initiative
- Early Detection: Establish rigorous monitoring protocols for fuel levels and hull integrity.
- Rapid Response: Define streamlined procedures for immediate containment in case of accidental release.
- Policy Development: Translate lessons learned into regulatory guidelines for maritime safety.
Implications for International Maritime Safety
This methodology has been highlighted by experts as a potential blueprint for governments worldwide that handle potentially polluting wrecks (PPWs).
PPWs are vessels that carry significant quantities of fuel—either onboard cargo or their propulsion reserves. If these tanks rupture or the wreck deteriorates, the resulting environmental damage can be catastrophic. Across the Baltic Sea and the South Asia‑Pacific regions, several such wrecks are already leaking, posing threats to:
- Marine ecosystems
- Fisheries
- The well‑being of local coastal communities
Moving Forward
By adopting the lessons from the HMS Cassandra assessment, nations can proactively mitigate risks, protect ecological integrity, and safeguard communities that depend on healthy marine environments.
Project Tangaroa Urges Global Action to Safeguard Sunken Warships
Overview
A comprehensive map of submerged warships—red for Axis vessels and blue for Allied ships—has recently been released, featuring an estimated 8,500 potentially hazardous wrecks. The majority of these vessels date back to World War I and II, and experts warn that the actual figure could be considerably higher due to limited data.
After 80–110 years underwater, many of these wrecks are becoming increasingly unstable. To address this growing risk, Project Tangaroa, a global consortium of maritime experts coordinated by the Lloyd’s Register Foundation, The Ocean Foundation, and Waves Group, has called for urgent measures at the UN Oceans Conference (UNOC3) in Nice earlier this month.
Key Issues Highlighted by the Call to Action
- Degeneration of hull integrity leading to potential releases of toxic materials.
- Risk of marine pollution from decaying ammunition and fuel stores.
- Threat to marine biodiversity in critical habitats.
Collaborative Efforts and Success Stories
- Project Tangaroa facilitated cooperation between the UK and Estonian governments concerning the HMS Cassandra, setting a precedent for future partnerships.
- Stakeholders are encouraged to form similar agreements to identify and secure other vulnerable wrecks.
- Expert networks remain actively engaged to create comprehensive monitoring protocols.
Statement from Project Tangaroa’s Programme Manager
Lydia Woolley, overseeing Project Tangaroa at the Lloyd’s Register Foundation, emphasizes that the most effective solution hinges on joint action: “The solution to basically every issue and every point we raise is collaboration.”
Next Steps
Governments, NGOs, and maritime industries are urged to:
- Incorporate wreck assessments into national maritime safety regulations.
- Allocate resources for regular inspections and preventive maintenance.
- Engage in public outreach to raise awareness of maritime heritage conservation.
By pooling expertise and resources, the international community can mitigate the regulatory and ecological threats posed by these submerged relics and preserve maritime history for future generations.
A looming climate threat
Accelerating Threat to Oceanic Wrecks
Natural Degradation on the Seafloor
Seafloor wreckage has long been succumbing to corrosion, a gradual process that unfolds over decades of prolonged immersion. In a stable environment, the deterioration of metal and composite materials proceeds at a predictable pace.
Climate‑Driven Acceleration
- Rising Temperatures – Warmer waters increase the rate at which corrosive reactions occur, speeding up the breakdown of wreckage.
- Shifting Acidity – Ocean acidification, a direct outcome of higher atmospheric CO₂, enhances metal corrosion by lowering the pH and increasing ion availability.
- Intensified Weather Events – Typhoons, storm surges, and other extreme phenomena now hit more frequently and with greater force. These forces apply additional stress to structures already weakened by corrosion.
Human Activities Adding Pressure
The impact of industrial practices compounds the climate effects. Bottom trawling and deep-sea mining introduce physical disruptions and potential for scavenging lobby. The intersection of climate change and these growing oceanic industries raises the risk of accidental releases from PPWs—plan and placement wrecks that serve as environmental “time bombs.”
Implications for Ocean Health
The accelerated breakdown shortens the already precarious life span of these submerged structures, turning them into ticking environmental threats. Effective monitoring and regulation are now essential to mitigate the expanding risks posed by both natural climate change and human exploitation.
Data, data, data: The need for international collaboration
UK MOD’s SALMO Team Paves Path for Project Tangaroa Amid Wreckage Mysteries
Why Precise Data Matters
To anticipate and mitigate potential environmental crises, scientists and policymakers demand comprehensive information. However, the knowledge base about warship wrecks—such as their exact positions, structural integrity, and lingering pollutants—remains surprisingly fragmented and hard to access.
SALMO’s Long‑Standing Role
The Sea Air Land Operations (SALMO) unit of the UK Ministry of Defence has been working closely with Project Tangaroa since its launch. Their expertise in wreck management has proven crucial in mapping and monitoring the submerged relics of the World Wars.
Insights from the Field
Matt Skelhorn, head of the MOD Wreck Management Programme, highlights a significant knowledge gap:
- While the total number of ships lost during World Wars I and II is well documented, many wrecks remain undiscovered.
- Older records provide approximate sinking locations, but precise coordinates are often uncertain.
- Deep‑water and remote wrecks rarely receive systematic surveys, leaving their conditions largely unknown.
- Even in well‑surveyed zones, misidentifications of wrecks result in inflated risks and inaccurate pollution estimates.
Moving Forward with Project Tangaroa
Project Tangaroa aims to fill these gaps by employing advanced sonar technology, automated mapping, and accurate data integration. With SALMO’s support, the initiative will:
- Survey unexplored wreck sites across the Atlantic and Mediterranean.
- Verify and correct existing wreck identification records.
- Assess environmental hazards to guide remediation strategies.
By systematically revealing the hidden silt‑covered artifacts of past conflicts, Project Tangaroa will provide governments and environmental agencies with the reliable, actionable data needed to protect marine ecosystems and preempt catastrophes.
HMS Cassandra Wreck Survey
In 2021, HMS Echo conducted an extensive survey of the wreck of HMS Cassandra, a Royal Navy vessel that lies beneath the waves. The dive team collected data on the ship’s structural integrity and its surrounding marine environment.
Marine Life & Tourism Benefits
- Creates a dynamic, biodiverse coral reef habitat.
- Supports local fisheries by providing additional feeding grounds.
- Attracts divers, boosting regional tourism revenue.
Cultural Heritage & War Graves
Many wrecks serve as final resting places for crews lost at sea. Some are formally recognized as war graves and are protected under cultural heritage legislation.
Assessing Pollution Consequences
Environmental experts emphasize that wrecks pose both pollution risks and unique ecological opportunities. “They are potentially polluting, yet they also form vibrant coral ecosystems,” remarks Woolley.
Multifaceted Challenges
- Balancing hazardous material management with ecological preservation.
- Addressing legal protections for relics classified as heritage sites.
- Ensuring public access without compromising safety.
Project Tangaroa Initiative
Project Tangaroa aims to tackle the “multifaceted problem” by promoting knowledge sharing across the industry. Woolley outlines three core strategies:
Key Strategies
- Digitising archives to make historical data publicly available.
- Tracking financial resources dedicated to wreck management.
- Leveraging research vessel data and advanced modelling to predict oil spills and minimize impact.
Early Successes
Since the proposal, the initiative has fostered collaboration between the Estonian and UK governments, among others, and has produced tangible outcomes in waste reduction and resource allocation.
Navigating ‘loopholes’ and legacies
Wreck Management: Who Holds the Responsibility?
1. The Existing Regulatory Gap
At present, the framework governing cleanup of wrecks has a loophole. The prevailing arrangements focus on emergency response for contemporary incidents involving privately owned and operated vessels. This differs fundamentally from the challenges posed by Privately Owned Actors (POAs) and Wrecks (PPWs). Additionally, many agreements explicitly exempt legacy wrecks and wartime casualties from their scope.
2. Protocols That Cover New Wrecks
Several international protocols exist, such as the 2007 International Maritime Organization’s Wreck Removal Convention and the International Oil Pollution Compensation Fund (IOPCF). These provide:
- A legal framework for removing wrecks hazardous to marine environments.
- A compensation system for oil pollution damage.
However, these instruments only enforce obligations for oil spills from wrecks occurring after their enactment and they apply primarily to privately owned ships; state-owned wrecks remain outside this coverage.
3. Sovereign Immunity and Flag State Rights
State-owned sunken vessels, such as those flagged by the US, Germany, Japan, and the UK, are considered continuously owned by their flag state unless explicitly abandoned. Under sovereign immunity, these PPWs cannot be legally compelled to act, and international intervention requires flag‑state consent.
Consequently, cooperation from flag states is critical, yet it currently relies largely on goodwill, moral obligation, or geopolitical considerations.
4. Practical Challenges for Coastal Nations
Some states have taken proactive steps to assess PPW risks within their waters, and occasionally in other countries. Yet many nations with high numbers of wrecks lack the:
- Resources and finances to conduct comprehensive risk assessments.
- Capacity to develop robust management plans.
These countries often depend on flag states to address dangers on a case‑by‑case basis, rather than through a systematic approach.
5. The Need for an International Legal Framework
Even if existing resources can be applied to PPW spills, achieving this requires extensive negotiations over funding, further exposing coastal states to vulnerability. As Lydia Woolley, Project Tangaroa’s program manager at the Lloyd’s Register Foundation, notes: “If you’re trying to figure out who’s responsible for months before you can even begin remediation, that’s catastrophic.”
Woolley emphasizes that a small, uncontrolled escalation can turn into a major crisis when responses are delayed or absent.
Ultimately, some individual wrecks have been addressed in response to an identified oil leak or intervention request. But the proactive, systematic approach needed to tackle the problem at scale remains absent. An established international legal framework is essential to bridge these gaps and enable coordinated action.
Seven key calls to action
Project Tangaroa Unveils the Malta Manifesto: A Call for Swift Action Before 2039
Against the looming backdrop of the 100th anniversary of World War II in 2039, Project Tangaroa has released the Malta Manifesto at UNOC3, urging governments worldwide to act decisively now, before the situation deteriorates beyond recovery.
Structured Framework for a Precautionary Approach
The manifesto delineates a comprehensive strategy for tackling the growing crisis within the next four decades. Its core principles highlight:
- Precautionary policy development
- Strengthened global cooperation
- Long‑term, sustainable solutions
Seven Key Calls to Action
Project Tangaroa’s recommendations span several crucial domains, aiming to empower a broad spectrum of stakeholders—governments, industry, researchers, and civil society—across the globe.
- Secure adequate financing for mitigation and adaptation efforts.
- Establish consistent standards and best practices.
- Integrate regional and national planning frameworks.
- Foster innovation in technology and methodology.
- Provide comprehensive training programs for affected communities.
- Promote open data sharing and accessibility.
- Launch an international PPW Finance Task Force to champion cooperative financing solutions.
International PPW Finance Task Force
The manifesto specifically emphasizes the creation of a dedicated task force to drive joint efforts across borders, enabling the introduction of creative financial instruments that can scale up necessary interventions.
Message of Hope and Urgency
According to Woolley, the advocacy is “not fatalistic—it is an urgent encouragement.” He notes that the global expertise assembled by Project Tangaroa has already uncovered effective methods to manage the risks linked to the wrecks. However, to implement these solutions on a meaningful scale, “resources” are essential.
By establishing clear, actionable steps, the Malta Manifesto serves as a roadmap that invites collective responsibility and decisive timing before the approaching century‑mark.
