ICJ’s Pulp Mills on the River Uruguay Judgment: Development of Law on Shared Watercourses

By Valerie Oosterveld

Cross-referencing: Chapters 5(a), 11(B)(1) at p. 720; 11(B)(2) at p. 723; and 11(C)(2) at 730. 

On April 20, 2010, the International Court of Justice (ICJ) released its judgment in the case of Pulp Mills on the River Uruguay (Argentina v. Uruguay). The dispute centered around a cross-border environmental dispute regarding Uruguay’s authorization of the construction of two pulp mills on the River Uruguay, the river demarcating the boundary between Argentina and Uruguay. The first pulp mill is referred to as the Orion (Botnia) pulp mill. It has been in operation since November 2007. Argentina strongly objected to the construction of this mill, fearing harm to its environment. The other pulp mill has been planned but not built, and is referred to the CMB (ENCE) pulp mill. Argentina submitted the dispute to the ICJ in 2006. Uruguay successfully argued that the dispute was narrowly limited to the interpretation or application of the 1975 Statute of the River Uruguay, and therefore Argentina’s concerns regarding air, noise and visual pollution were largely excluded from consideration (para. 52). 

The ICJ held that Uruguay was obligated by the 1975 Statute to notify Argentina before deciding on the environmental viability of the planned pulp mills, and that Uruguay breached this obligation (para. 122). The ICJ also held that the remedy for Uruguay’s failure was the Court’s declaration of the breach (para. 269). The Court also held that there is no conclusive evidence in the record to demonstrate that Uruguay failed to act with the requisite degree of due diligence or that discharge from the pulp mill has had a harmful effect on the water quality or ecology (para. 265).

The Court made several significant statements on shared watercourses. The Court indicated that a balance must be struck between the rights and needs of each riparian state to use the river for economic and commercial purposes and their obligation to protect it from environmental damage: this is the objective of sustainable development (paras. 175, 177). “[U]tilization [of the river] could not be considered equitable and reasonable if the interests of the other riparian state in the shared resource and environmental protection of the latter were not taken into account” (para. 177). Similarly, the ICJ observed that parties to the 1975 Statute are required to adopt domestic pollution prevention and aquatic preservation regulations and measures that meet international standards, and the Court reminded both states of their obligation to ensure that activities within their jurisdiction and control respect the environment of other States or of areas beyond national control (paras. 193, 195, 197).

The ICJ noted that environmental impact assessment “has gained so much acceptance among States that it may now be considered a requirement under general international law to undertake an environmental impact assessment where there is a risk that the proposed industrial activity may have a significant adverse impact in a transboundary context, in particular, on a shared resource” (para. 204). However, the Court also noted that general international law does not prescribe the scope or content of such assessments (para. 205).
While Argentina argued that the precautionary approach of the 1975 Statute shifts the burden of proof to Uruguay to show that the Orion (Botnia) plant would not cause significant damage to the environment, the ICJ ruled that Argentina, as the applicant, has the burden of proof (paras. 160, 162, 164).