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The past, present and future of the London Convention and London Protocol

2023-10-24 Gary Howard
The London Convention and London Protocol transformed the way nations and industries dispose of waste at sea, and 51 years on from its adoption, the convention is still evolving.

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As green and sustainability considerations take centre stage in today’s modern regulatory landscape, it is perhaps surprising that the most significant regulation affecting dredging and its impact on the environment was adopted more than half a century ago. However, the London Convention’s objective to prevent the dumping of waste and other matter that pollute our oceans is more relevant than ever. And it is constantly evolving. In the years to come it will cover issues from geoengineering of oceans to address climate change to jettison from space rocket launches.

The Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter 1972 or ‘London Convention’ came at a time of widespread ocean neglect due to activities ranging from the dumping of industrial wastes and sewage sludge at sea to the incineration of waste offshore. The Convention is a treaty under the UN’s International Maritime Organization (IMO) and has around 100 signatories, member nations who are obligated to implement the provisions of the London Convention.

“Essentially, the London Convention says: ‘Why do you have to dump that waste in the ocean? Can’t you feasibly and safely put the material on land somewhere? The ocean is to be your last resort,” Craig Vogt, Ocean & Coastal Environmental Consulting, told CEDA Industry News.

The London Convention and Protocol have evolved significantly during Vogt’s career, including with his input and direction. He believes the London Convention and Protocol are an example of what regulation can accomplish. Dumping at sea of radioactive wastes, industrial wastes, sewage sludge, and incineration at sea have been banned, while waste allowed for disposal in the ocean are tightly controlled.

“I think the London Convention and Protocol have made a huge difference in the quality of the oceans and controlling ocean disposal. International regulation moves very slowly, but it's remarkable how many things have been accomplished in such a short timeframe.”

Carbon capture and storage has recently made its way into maritime industry headlines as we look for sustainable future fuels, but guidelines on carbon dioxide sequestration and disposal under the sea bed were produced by the London Protocol back in 2006. The guidelines deal with the considerations around injecting captured CO2 beneath the sea bed for long term storage in rock formations and depleted oil and gas fields to combat global heating and climate change. “We prepared those guidelines in a year,” said Vogt.

From Convention to Protocol

In 1996, the London Protocol was agreed as a means to modernise the convention and, eventually, replace it altogether. Instead of a list of substances which cannot be dumped in the ocean, the London Protocol has what is known as the ‘reverse list’ which defines categories of materials which can be dumped in the ocean with an appropriate permit certifying compliance with the waste assessment guidelines.

The waste assessment guidelines were initially developed in the early 1990s and have been updated and revised to produce specific guidelines for each waste category in the ‘reverse list.’ The waste assessment guidelines are integral to the success in controlling dumping of wastes into the oceans. The guidelines provide for waste prevention, characterization of physical, chemical, and toxicological aspects of wastes, waste disposal alternatives, designation of disposal sites, preparation of action levels, risk assessment, monitoring, and issuance of permits with disposal conditions. Specific waste assessment guidelines for dredged material were updated in 2014 (See - Dredge Material Waste Assessment Guidelines 2014).

Vogt spent 35 years working at the headquarters of the US Environmental Protection Agency (EPA). He led the USA delegation to the London Convention and Protocol scientific group meetings from 1991 to 2003, was elected chair of the scientific group from 2003-2007, and has since represented CEDA on behalf of the World Organization of Dredging Associations (WODA) at meetings of the London Convention & Protocol. As a consultant, Vogt has produced regulatory support documents for the Secretariat of the London Convention.

“The main waste going into ocean waters is dredged material, and thus dredged material has been the focus of the Convention and Protocol for a long time. There has been more experience in assessment, characterization, and monitoring of dredged material disposal than for any other wastes under the Convention and Protocol,” said Vogt.

The initial guidelines for disposal covered all waste materials being dumped into ocean waters. Specific guidelines have since been developed for each individual category on the reverse list: dredge materials; sewage sludge; fish wastes; vessels and platforms; inert, inorganic geological material; organic material of natural origin; and bulky items primarily comprising iron, steel and concrete. Sewage sludge was removed from the list in 2022 by agreement of the Protocol member countries.

Guidelines have also been established for development of action lists and action levels for toxic chemicals in dredged material, setting a lower level of concern and higher level of concern for the listed toxic substances. If levels of toxicity are above the higher level, a material is deemed toxic and cannot be deposited in the ocean, below the lower level a material can be deposited, and in between the levels there is a need for further assessment and study.

In 2014, the waste assessment guidelines for dredge material underwent a major update to reflect scientific and technical developments in the field. Since then, another significant change affecting the dredging industry was adoption of disposal site designation guidelines. These guidelines lay out the baseline surveys that should be done at a proposed site before depositing dredged materials, covering chemical, physical and biological assessments, and considering risks of bioaccumulation of toxic chemicals and chronic toxicity.

Developing Support

Alongside building progressively more robust and detailed regulation to protect the environment, the London Convention & Protocol have kept a keen eye on the barriers to full compliance with implementation of waste assessment guidelines and other key elements of the Convention and Protocol. Understanding that developing countries may not have the resources for all of the monitoring and assessment recommended by the various rules, guidelines were produced on low cost, low technology monitoring for dredge materials including separate guidance documents for field monitoring and compliance monitoring.

Developing nations have been a consideration in the London Protocol since its inception - the inclusion of ‘bulky items primarily comprising iron, steel and concrete’ in the reverse list was specifically to address the concerns of small island nations with no practical way of disposing of these wastes on land.

In 2020, the decision was made to assess the Protocol’s broad experience of toxicity and chemical levels in dredge materials around the world to generate a list of chemicals in dredged material and their acceptable levels for disposal in ocean waters. “Developing countries don't necessarily have the capacity to do toxicity testing. Chemical testing is cheaper and easier – still not easy, but doable – and thus developing nations can use the chemical action levels to determine whether permits for disposal in ocean waters should be issued,” said Vogt.

Future Developments

The London Convention and Protocol has a number of niche subjects to assess in the coming years, from jettisoned material from space launches that fall into the ocean, marine litter and plastics, and vessel paints and anti-fouling coatings that are washed into the ocean during ship operations and hull cleaning.

Marine geoengineering will also be a key subject in the future, said Vogt, as regulators seek to prevent any unwanted side effects from those using the ocean, its flora, fauna and processes to reverse climate change.

“On dredged material, we’ve really done a lot over the years and we have some pretty good guidelines. We're pretty well settled, I think, on regulatory prospects,” said Vogt. The guidelines on dredged materials will likely be reappraised around the middle of this decade, a process he expects will be one of refinement rather than an overhaul. Because dredged material is a resource, especially in view of climate change, rising sea levels, and eroding shorelines, a work group has been initiated on beneficial use of dredged material (and other
waste materials).

To access the guidelines mentioned above for dredged material and to read more about CEDA’s work on the London Convention & Protocol visit

LC/LP: Guidance on disposal site selection 2021

LC/LP: Guidance on dvelopment of interim default action levels 2020

LC/LP: Dredged material waste assessment guidelines 2014

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