The Helsinki Rules on the Uses of the Waters of International Rivers

The Helsinki Rules on the Uses of the Waters of International Rivers is an international guideline regulating how rivers and their connected groundwaters that cross national boundaries may be used, adopted by the International Law Association (ILA) in Helsinki, Finland in August 1966. In spite of its adoption by the ILA, there is no mechanism in place that enforces the rules. Notwithstanding the guideline's lack of formal status, its work on rules governing international rivers was pioneering. It led to the creation of the United Nations' Convention on the Law of Non-Navigational Uses of International Watercourses. In 2004, it was superseded by the Berlin Rules on Water Resources.

Applicable to all drainage basins that cross national boundaries, except where other agreement between bordering nations exists, the Helsinki Rules assert the rights of all bordering nations to an equitable share in the water resources, with reasonable consideration of such factors as past customary usages of the resource and balancing variant needs and demands of the bordering nations. It also mandates protection of the resource by bordering nations with respect to water pollution in Chapter 3 (Articles IX to XI) and sets forth recommendations for resolving disputes over usage of such watercourses.

The Helsinki rules consist of 37 articles spread over 6 chapters.

Chapter 2, Article 4 states: "Each basin State is entitled, within its territory, to a reasonable and equitable share in the beneficial uses of the waters of an international drainage basin".

In determining what is reasonable and equitable share, all relevant factors are to be considered together and a conclusion reached on the basis of the whole. The list provided in Article 5 (2) is produced in full below:

1. The geography of the basin, including in particular the extent of the drainage area in the territory of each basin State

2. The hydrology of the basin, including in particular the contribution of water by each basin State

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