Gabcikovo-Nagymaros Project (Hungary/Slovakia)

Brief Fact Summary. Hungary (P) claimed that Czechoslovakia (D) violated the provisions of a treaty when it appropriated the waters of the Danube River to construct a dam.

Synopsis of Rule of Law. Watercourse states shall participate in the use, development and protection of an international watercourse in an equitable and reasonable manner.

Facts. In 1977, Hungary (P) and Czechoslovakia (D) signed a Treaty for the construction of dams and other projects along the Danube River that bordered both nations. Czechoslovakia (D) began work on damming the river in its territory when Hungary (P) stopped working on the project and negotiation could not resolve the matter which led Hungary (P) to terminate the Treaty. Hungary (P) based its action on the fact that the damming of the river had been agreed to only on the ground of a joint operation and sharing of benefits associated with the project, to which Czechoslovakia (D) had unlawfully unilaterally assumed control of a shared resource.

Issue. Shall watercourse states participate in the use, development and protection of an international watercourse in an equitable and reasonable manner?

Held. Yes. Watercourse states shall participate in the use, development and protection of an international watercourse in an equitable and reasonable manner. Hungary (P) was deprived of its rights to an equitable and reasonable share of the natural resources of the Danube by Czechoslovakia (D) and also failed to respect the proportionality that is required by international law. Cooperative administration must be reestablished by the parties of what remains of the project.

Discussion. The Court’s decision was that the joint regime must be restored. In order to achieve most of the Treaty’s objectives, common utilization of shared water resources was necessary. Hence, the defendant was not authorized to proceed without the plaintiff’s consent.