Berlin Rules on Water Resources

The Berlin Rules on Water Resources is a document adopted by the International Law Association (ILA) to summarize international law customarily applied in modern times to freshwater resources, whether within a nation or crossing international boundaries. Adopted on August 21, 2004, in Berlin, the document supersedes the ILA's earlier "The Helsinki Rules on the Uses of the Waters of International Rivers", which was limited in its scope to international drainage basins and aquifers connected to them.

In 1966, the ILA adopted "The Helsinki Rules on the Uses of the Waters of International Rivers", an unenforceable guideline governing the usage of rivers and connected groundwaters that crossed national boundaries. As the guideline did not address other aquifers, various other guidelines were subsequently drafted and adopted by other organizations to replace or supplement them, including the United Nations' "Convention on the Law of Non-Navigational Uses of International Watercourses" and the ILA's own "Rules on International Groundwaters." However, these documents were restricted to addressing international waters. In 1996, the ILA appointed Joseph Dellapenna to produce a compilation of water related laws, following the production of which in 1997 it decided to create a comprehensive document, addressing all freshwater resources as well as issues affecting the climate that impacts them.

The document requires that nations take appropriate steps to sustain and manage water resources, in conjunction with other resources, and minimize environmental harm. In addition to setting out various regulations for nations to follow with respect to water within their boundaries and water they may share, it regulates behavior in wartime, including damage to water installations such as dams and dikes. Nations are not permitted to take action that may result in a shortage of life-sustaining water for civilians, unless a nation being invaded is compelled by military emergency to disable its own water supply, or that may cause undue ecological damage. Poisoning water necessary for survival is in all cases forbidden.

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