162 – Dispute over the Status and Use of the Waters Silala (Chile vs Bolivia)

On June 6th, 2016, the Republic of Chile filed before the International Court of Justice (the ICJ) an application instituting proceedings against the Plurinational State of Bolivia concerning the status and use of the waters of the Silala (also known as Solili) by the two States.

Chile contends that the waters of the Silala are a watercourse of an international dimension, taking its origins in Bolivia before crossing the Chilean border. Therefore, both States would have the right to freely use these waters. It asserts that this position was implicitly accepted by Bolivia, as shown in certain geographical and topographical treaties dating from the early twentieth century before Bolivia changed its mind in 1999. According to the assertions contained in the application initiating the proceedings, the Chilean authorities claim to have made several attempts to settle definitively this issue of the status and use of the waters through diplomatic channels without reaching an agreement with Bolivia and Chile felt they had no other choice than to initiate proceedings before the ICJ.

The public hearings were opened on April 1st, 2022. The International Court of Justice delivered its judgment on the merits on December 1st, 2022. It first ensured that it had jurisdiction to hear the case and its admissibility. 

Turning first of all to the main pleas:

  • Chile wishes to have the Silala declared an international watercourse to which customary international law should apply: during the hearings Bolivia agreed that the Silala was indeed a river of an international character and that international law was applicable. The Court concludes that Chile’s claim has become devoid of purpose and that there is therefore no basis for adjudication.
  • Chile wishes to use the waters of the Silala in a fair and reasonable manner, which Bolivia had initially disputed: the Court observes that during the written and/or oral proceedings, the positions of the parties have evolved and they have reached agreement on this point. There is therefore no basis for a ruling.
  • Chile is entitled to use the waters of the Silala as it currently does: again the parties have agreed that Chile is entitled to reasonable and equitable use of the waters of the Silala and that its right to any future use is without prejudice. Bolivia has the same right. The claim made by Chile has therefore become devoid of purpose and there is no reason to adjudicate.
  • Chile would like the Court to order Bolivia to take all appropriate measures to reduce and prevent ecological and transfrontier  damage: the parties agreed that they had the duty to prevent tranfrontier damage. The Court notes that the parties have reached agreement on this point, so there is no matter to adjudicate.
  • Chile requests the Court to order Bolivia to cooperate with the Government of Chile and to notify it of any measures taken which would affect the use of the waters of Silala and the negative and/or harmful consequences that might result for Chile. The 2 parties admit to having the same right over the use of water. The Court notes that there is an obligation under customary international law for a State to inform, notify or prevent any risk of material harm to the other State. In the present case, there is nothing in the documents provided by Chile to prove that the projects undertaken by Bolivia present a risk of damage, let alone a risk of important damage for the Chilean State. The Court therefore rejects this plea.

Turning to Bolivia’s counter-claims, the Court first examined whether the degree of connection in law and in fact between the principal claims and counter-claims is sufficient for those claims to be examined in the same proceedings and concluded in the affirmative.

  • Bolivia would like the Court to confirm that its country has sovereignty over the artificial canals and other infrastructure built on the waters: the parties have agreed that the artificial canals, channels and other drainage infrastructure were within Bolivia’s territory and that Bolivia exercised a natural sovereignty. The Court notes that there is no longer any disagreement between the parties on these points. The right to maintain and/or dismantle infrastructure must be applied in accordance with customary international law with particular regard to possible transfrontier damage. The counterclaim has become devoid of purpose, so there is no need to adjudicate.
  • Bolivia has sovereignty over the waters of the Silala, whose flow has been artificially increased. The parties having finally agreed on the international nature of all the waters of Silala, the application becomes devoid of purpose. Bolivia is now seeking a declaration that the right in question is not an acquired right and does not prejudge anything about the future, which Chile agrees to. There is no longer any disagreement between the parties on this point.
  • Bolivia requests the court to adjudge and rule that any Chilean claim for potential future compensation as a result of the dismantling of the infrastructure will be inadmissible. The Court confirms its settled case-law and does not rule on hypothetical cases, it cannot decide and therefore dismisses this counterclaim.

This summary is provided for informational purposes only, does not involve the responsibility of Dome and should in no way be used as a substitute for a careful reading of the judgment and order of the case.