The Conflict Over the Atuel River in Argentina

• Date: 01 March 2018

48 ELR 10220 ENVIRONMENTAL LAW REPORTER 3-2018

I. The Atuel River: An Introduction

to the Case

In a historic ruling1 that bega n to shape the solution to a

conict that has been going on for more than 70 years,

the Supreme Court of A rgentina ordered in 2017 that the

province of Mendoza, together with the province of La

Pampa, should allocate the water ow of the Atuel River

within 30 days in order to enable restoration of the eco-

system that was aected in the northwest of La Pampa by

the Los Nihuiles dams. In the ruling, the Argentine high

court ordered that the two provinces, together with the

national government, submit a work plan for allocation of

the waters of the Atuel River.2 e court imposed a dead-

line of 120 days to submit the plan.

is conict is old. At the beginning of the 20th cen-

tury, the Atuel River’s ow began to diminish due to the

construction of private water works and dams, but in 1947,

Mendoza started the construction of a dam that ended

up dr ying out the northwest of La Pampa province. e

waters of the Atuel River stopped reaching the Pampean

towns of Santa Isabel and Algarroba del Águila. erefore,

a diaspora began and hundreds of settlers abandoned their

towns, unlike the Mendoza department of General Alvear,

which managed to continue developing. La Pampa began

to depend economically on Mendoza.

e Supreme Court had already ruled in 1987 that the

river was interprovincial. In addition, the ruling granted

to Mendoza a quota for the irrigation of 72,000 hectares

in southern Mendoza, in the areas of General Alvear and

San Rafael, and exhorted it to enact measures to make this

irrigation more ecient, such as leak-proong, conduc-

1. Corte Suprema de Justicia de la Nación [CSJN] [National Supreme Court

of Justice], 243/2014 (50-L), “Province of La Pampa vs Province of Men-

doza on the Use of Water” (Arg.). See complete ruling in Spanish at http://

www.cij.gov.ar/nota-28 698-Conicto -Río-Atuel-- la-Corte-ord en--a-las-

provincias-de-La-Pampa-y-Mendoza-la-presentación-de -un-programa-de-

obras-con-la-participación-del-Estado-Nacional.html.

2. e Atuel River rises in the Andes, fed by snow. In 1914, it had a route of

almost 800 kilometers (km) and ended at the Colorado River after crossing

La Pampa.

tion, and execution of marginal channels. us, the sur-

plus water for Mendoza resulting from the quota granted

by the ruling would force the province to negotiate and to

make “interprovincial agreements” in order to benet La

Pampa at the same time. La Pampa alleged that the rul-

ing was never implemented, and initiated a lawsuit in 2014

for environmental and social da mage. It demanded a con-

tinuous ow of ve cubic meters per second to repair the

environmental damage, an improvement of the eciency

of irrigation in Mendoza and leak-proong of the riverbed,

and the construction of a reservoir.

During public hearings that were held at the Supreme

Court in 2017, La Pampa alleged that it was robbed of the

Atuel River, which caused an environmental catastrophe,

in addition to profound social, economic, and emotional

damage suered by the inhabitants in the western part of

the province. Mendoza, on the other hand, arguing that it

was not reasonable to ask the desert for water,3 stated that

97% of the territory was desert, and pointed out—in order

to indicate its ecient use of water—that the Diamante,

Mendoza, Tunuyán, and Atuel Rivers had a combined ow

that was 1% of the Paraná R iver, South America’s second-

longest river.4 Mendoza accused La Pampa of only doing

waterworks in the eastern part of the province.

3. During the Public Hearing held at the Supreme Court of Argentina, after

all the parties presented their grounds before the Tribunal, the Governor of

Mendoza explained:

ere are possibilities of agreement. Mendoza is always open to

agreements. La Pampa has built a myth about a stolen river that

harms the northwest of La Pampa, but they have done nothing to

make that sector of their province not arid. ey could have redi-

rected the Colorado River or made a dam for the water that comes

from the Atuel sporadically, and then distribute it.

In this context, he added, “It is not reasonable to ask the desert to deliver

water.” Prensa Gobierno de Mendoza, Cornejo: “No Es Razonable Pedirle al

Desierto que Entregue Agua,” M G (June 14, 2017), http://

www.prensa.mendoza.gov.ar/cornejo- no-es-razonable-pedirle-a l-desierto-

que-entregue-agua/.

4. e Paraná River rises on the plat eau of southeast-centra l Brazil and ows

generally south to the poi nt where, after a course of 4,880 km , it jo ins

the Uru guay River to for m the extensive Rí o de la Plata estuary of the

Atlantic Oce an.

The Conf‌lict Over the Atuel

River in Argentina

by Ricardo Lorenzetti

Ricardo Lorenzetti is the Chief Justice of Argentina, an Organization of American States (OAS) Goodwill Ambassador

for Environmental Justice, Member of the United Nations Environment Programme (UNEP) Advisory Council for the

Environmental Rule of Law, and Member of the Environmental Justice Commission of the Ibero-American Judicial Summit.

Copyright © 2018 Environmental Law Institute®, Washington, DC. Reprinted with permission from ELR®, http://www.eli.org, 1-800-433-5120.