1. Historic background and munition distribution
After World War I and II, large amounts of munition were dumped in German territorial waters and the German exclusive economic zone (EEZ). By far the largest amount of munition after WW II was sunk in dedicated dumping areas. Experts assume that a total of 1.6 million tonnes of conventional munition were dumped. This number is uncertain but appears realistic considering the German munition stock at the end of WW II. Furthermore, an expected 5,090 tonnes of chemical munition and warfare agents were dumped in the German waters of the North Sea and the Baltic Sea. In addition to defined dumping areas, conventional munition entered the seas during combat, military manoeuvres, and accidents at sea, although exact numbers and locations are difficult to assess. Munitions can also be found in the waters of our European neighbours. The waters of the United Kingdom are particularly heavily contaminated.
2. Threat to Humans
Similar to munition on land, marine explosive ordnance poses a threat to people who come into contact with it. Although an accidental detonation, e.g. during anchoring, is rather unlikely, the possibility exists as a latent threat. People and commercial entities who actively interact with the seafloor are certainly subject to higher risk of accidentally interacting with munition. This includes, among others, fisherpersons and people in the dredging industry. In addition, tourists can find parts of munition objects, explosives or white phosphorous on beaches. By profession, employees in public and private explosive ordnance disposal (EOD) squads face the highest risk. Finally, since the largest amount of dumped munition lies close to the coast in rather shallow waters, it could come into the possession of unauthorised people.
3. Environmental Impacts
Many explosive compounds are toxic, carcinogenic, and mutagenic (e.g. TNT and its metabolites). Munition objects on the seafloor have been corroding for at least 77 years, and some dumpsites have large amounts of open explosive material present. Here, dissolved munition compounds can be detected in the water, sediment, and biota. Dissolved TNT concentrations close to exposed explosive surfaces can be 10 to 100 times higher than in comparable areas without munition contamination.
Furthermore, higher concentrations of TNT and TNT metabolites have been found in mussels and fish from dumping sites compared to individuals from locations without munitions. Depending on the site and region, concentrations in flatfish (e.g., dab) vary. In the Kolberger Heide dumping area, they are approximately 100 times higher than in the Lübeck Bay and Outer Jade areas. It is particularly noteworthy that TNT and its metabolites have also been detected in the edible portions of flatfish from munitions disposal areas. These explosive substances have also been found in fish caught near munitions-contaminated shipwrecks in the North Sea. Analyses of mussel samples from environmental sample banks show a slight increase in explosives over the past decade. Studies of benthic biodiversity have revealed that some species are more prevalent in waters with elevated TNT concentrations.
4. Maritime Economic Impacts
In Germany, there are hardly any economic activities in known munition dumping areas. The munition dump sites are relatively small so that economic development in these areas is currently not necessary. Yet, whenever offshore activities interact with the seafloor, e.g. for technical installations (see section 1), detailed munition mapping is required and is potentially followed by a munition clearance operation. This issue is highly relevant for offshore renewable energy development. The planned widening of the fairway northeast of the island of Wangerooge is also noteworthy, as it will partly require the clearance of a munition dumping area. The cumulative cost of past clearance operations is unknown, but created technical innovations which precede development of technical methods to make the clearing of munition dump sites feasible.
5. Munition Detection Surveys
Several simultaneously usable methods exist to survey the seafloor for munition objects (magnetometers, seafloor mapping sonars, sub-bottom profilers). These surveys are typically undertaken by dedicated offshore mapping companies. During past and ongoing research projects, a number of dump sites in the North Sea and the Baltic Sea have been investigated. For some dump sites in the German Baltic Sea, a particularly comprehensive situational picture has been developed. These systematic investigations covered an area that – according to historic records – is presumed to contain approximately 100,000 tonnes of conventional munition.
6. Munition Clearance Technologies
Only specialised organisations and companies have the capability to remove munition from the complex and dynamic marine environment. In German coastal waters, federal EOD squads are responsible. In addition, some private companies exist in Germany – a rather unique industry in global context (see section 10 – Economic potential), as the military is solely responsible for munition clearance in most other countries. The strength of the private economy drives innovation in this sector. In Germany, most detected munition objects are removed and destroyed. Only a small number of items unsafe to handle are detonated on site. This type of in-situ detonation is much more common in other countries. Intentional detonations in the environment should be avoided, as detonations have negative effects on marine animals. In particular, marine mammals such as the protected harbour porpoise are impacted directly through the strong pressure wave. Additionally, toxic explosive remains can be distributed into the environment. Underwater munition clearance can be performed by using different types of technologies and methods such as divers, remotely operated vehicles (ROVs), or multi-tools attached to excavators or crawlers.
The ongoing immediate action programme “Munitions in the North Sea and Baltic Sea” aims, among other things, to explore the feasibility of clearing large quantities of munitions (primarily unfused) from dumping sites. Insights gained from pilot clearance operations are intended to lay the foundation for subsequent continuous clearance measures.
As part of the CONMAR project, a priority list of known munitions deposits is being developed in collaboration with relevant stakeholders. These sites should be addressed first once the immediate action programme is completed. To ensure a robust prioritisation process, data from the CONMAR consortium will be combined with information from a wide range of federal and state authorities using a federated management approach.
Links
Frey et al. 2019: Qualitätsleitfaden Offshore-Kampfmittelbeseitigung
Frey et al. 2023: Kampfmittel im Meer – Der Umgang mit Belastungsschwerpunkten
Frey 2024: UXO and environmental risk factors impacting EOD operations in German waters
Sichermann 2024: Das Sofortprogramm Munitionsaltlasten in Nord- und Ostsee
7. Munition disposal approaches
Munition disposal in Germany is executed at a number of institutions, the most important being the GEKA mbH in Munster, which is located far from the coast. The capacities of all existing disposal sites are currently exceeded, and any large-scale removal of marine munition would require interim storage sites either on land or underwater. To avoid this, plans exist to destroy munition directly at sea. The needed technological sub-systems do exist but they have not yet been integrated into a systemic technology chain. As part of the immediate action programme, the development of such a technology chain will be commissioned. Whether disposal at sea or at a dedicated area directly on the coast (or both approaches at the same time) is safer and easier/quicker to achieve has not yet been investigated in detail. Regardless of the facility's location, efficiency improvements in munition disposal are necessary to ensure that disposal can keep pace with recovery efforts.
8. National Dimension – Actors and Responsibilities
The issue of munition in the sea affects a large number of public and private actors. At the federal level, it touches on areas of responsibility of the BMUV, BMWK, BMBF, BMVg, BMDV and BMEL and their respective agencies. With the immediate action programme, the BMUV has effectively assumed responsibility for the issue. At the state level of each of the five coastal federal states, there are the ministries of the environment and of the interior, the latter represented by the state EOD squads. A regular exchange of representatives from the federal government and the states on the issue of marine munitions contamination takes place within the BLANO Expert Group “Munition in the Sea”. In addition, there are dedicated private specialist companies for the individual phases of explosive ordnance clearance – historical investigation, technical investigation, clearance and disposal. Furthermore, numerous relevant actors represent the interests of the environment.
In Germany, a multitude of relevant laws, regulations and legal frameworks exists for management of underwater munition. This is a consequence of the international, national and federal legal division of geographic areas at sea as well as the water-land transition which cannot be easily resolved.
9. International Dimensions
The munition is a global challenge, which opens up a multitude of opportunities to approach the issue. There are many formats for international cooperation on munition in the seas (e.g. in JPI Oceans, HELCOM, BSCP or NATO). Germany’s top-level research and its innovative companies should play a central role here. The international reputation of Germany offers potential sales opportunities for technical developments. The successful clearance of a munition dumping area will be an unprecedented proof of-concept, and will establish a starting point for international cooperation to clear marine munition. Together with the other Baltic Sea EU member states, Germany has committed to a range of measures, including the risk assessment of known areas and, where necessary, their subsequent clearance.
10. Economic Potential
Germany is one of the few countries where the handling of marine munitions does not fall under the responsibility of the navy. The entire procedure from munition surveys to recovery can – with the support of the EOD services of the federal states – almost entirely be undertaken by the commercial sector. Only the final treatment of munition and its fuses is usually carried out by the governmental partner institutions.
In the past, innovation in this sector was driven to a large extent by the construction of offshore wind turbines. The ambitious expansion targets for offshore wind therefore already offer interesting prospects for companies in this sector. In addition, the immediate action programme and the politically announced entry into large-scale explosive ordnance disposal increase growth opportunities and can thus trigger a noticeable surge in innovation. Furthermore, competition among companies leads to continuous reduction in costs and an increase in efficiency. In recent years, the developments in the areas of sensor technology, data evaluation and robotic systems illustrate the high innovation potential.
This offers local companies the opportunity to develop further high-tech solutions that create jobs and add value in Germany while also serving international markets.
11. Current Research Projects
In addition to the research projects that were mentioned throughout the text, the following further research and development projects with German participation exist:
- BorDEx: Development of an accelerated and mobile munitions disposal method
- CONMAR: Development of a comprehensive concept for the clearance of munitions in the German Baltic Sea
- CONMAR-2: Expansion of the CONMAR approach to the German North Sea (starting December 2024)
- IRAV: Development of a platform for industrial clearance of contaminated sites in disposal areas
- Marispace-X: Digital data space for munitions in the sea based on the European data infrastructure Gaia-X
- MMinE-SwEEPER: Development of technologies for munitions detection and clearance, as well as strengthening European cooperation
- MUNIMAP: Development of frameworks for authorities for the coordinated clearance of munitions across the Baltic Sea
- MuniRisk: Risk assessment of munitions in the Baltic Sea
- REMARCO: Management and monitoring of munitions in the North Sea
- Additionally, there are other toxicological assignments funded by the state of Schleswig-Holstein or the federal government
12. Contact Persons
Scientific Basis and Project CONMAR
Torsten Frey & Prof. Dr. Jens Greinert
DeepSea Monitoring Group, GEOMAR Helmholtz Centre For Ocean Research Kiel
Dr. Matthias Brenner
Section Ecological Chemistry, Alfred-Wegner-Institut
Prof. Dr. Edmund Maser
Institute of Toxicology and Pharmacology for Natural Scientists, University Medical School Schleswig-Holstein
Dr. Anita Künitzer
German Environment Agency
