This strategy features in the framework of Agenda 21 as formulated at UNCED (Rio de Janeiro, 1992), now coordinated by the United Nations Commission on Sustainable Development and implemented through national and local authorities. Agenda 21 recommends encouraging parties to the Convention on the Transboundary Effects of Industrial Accidents (London Dumping Convention) to take appropriate steps to stop ocean dumping and incineration of hazardous substances.
The London Dumping Convention (LDC) was a product of the 1972 Stockholm Conference on the environment, the London Dumping Convention outlawed the ocean disposal of nuclear and other highly toxic wastes. Eighty-seven nations are signatories at 2020.
At the 1987 North Sea Conference, the UK Government accepted an undertaking in principle not to dump materials in the North Sea unless there were no practical disposal alternatives on land. In 1990 it decided to ban all sewage sludge dumping at sea from the end of 1998 because practical alternative methods were becoming available. This commitment later became one of the requirements of the Urban Waste Water Treatment Directive adopted in 1991. Water companies have progressively introduced alternative methods of dealing with sludge and at the same time reduced the quantities.