Atuel-Chadileuvú River (Argentina)

Basin Overview

Located in Mendoza and La Pampa states, the Atuel-Chadileuvú River starts in the Cordillera de los Andes (13,000 ft), thus with a snow hydrological regime, with flow peaks in summer (Nov-Jan). The mean annual precipitation over the entire basin is highly variable from 100 to 1000 mm. The basin extends from the high mountains to the Patagonia plateau where it first joins the Salado river basin to form the Chadileuvú river. Before reaching the main Colorado river, in its lower part it is called Curacó river (see map).

The Atuel is traditionally known for its agricultural and hydroelectricity production (Nihuil and Valle Grande reservoirs) and tourism (Atuel Canyon). There is nearly 1000 km2 of agricultural land in the Atuel Basin, including peach, apple and pear orchards, vineyards, irrigated pastures and vegetables. Over the last 30 years, agriculture has begun to decline with an increasing number of abandoned farms. In contrast, tourism, mining and fracking are emergent water-demanding economic activities.

 

Facts and Figures

Country:  Argentina
Region: Mendoza/La Pampa (Interstate watershed)
Major Population Centers (people in 2018): General Alvear (28,000), Santa Isabel (3,000) and Algarrobo del Águila (1,000)

River Length: 485 km
Watershed Area: 3,800 km2
Köppen Climate Classification: Tropical and Subtropical Desert and Tropical and Subtropical Steppe

Source: Atuel Lake (Glacier)
Mean annual precipitation: 100 to 1000 mm/yr

Mouth: Chadileuvú River
Mean annual precipitation: 28 cm/yr
Mean annual discharge at mouth: 0.03 m3/s

People and Land Use

General Alvear (Mendoza) is the main city with 28,000 inhabitants. Towns in La Pampa are much less populated — Santa Isabel with 3,000 and Algarrobo del Águila with just 1,000.

Major landowners in the basin are private companies and individuals. Many large estates have little water that is limited to livestock drinking purposes. Irrigated lands are highly fragmented (80% of the farms are less than 10 hectares). 50% of the cultivated land is orchards, 25% vineyards, 10% irrigated pastures and 6% fresh vegetables.

Major Issues

The Atuel River has been heavily modified to support irrigated agriculture first and hydropower secondarily. Modifications include four dams and hundreds of kilometers of irrigation canals, diversions and drains. Recently with the reduction of water flows and the intensification of the hydrological cycle the basin has been facing droughts with consequences for agriculture, tourism and hydropower generation. The competition among these three main uses reveals a clear water-food-energy nexus.

Additionally, the long-standing interstate conflict between Mendoza and La Pampa provinces over the allocation and distribution of water has reached the national level in both judicial (Supreme Court) and political spheres (interstate political tension).  Finally, new water-demanding activities, like mining and fracking are increasingly threatening traditional water uses and users.

Research Ideas

  • To what extent, and how, are different water uses (agriculture, hydropower, tourism and recreation, and fracking) interrelated in water-resource (volume) terms and institutionally (use rights)?
  • River flows have been declining historically. How has this compromised or affected the water security of the various users?
  • Water has been managed under a very old law with strong institutional inertia. What are the main current weaknesses and challenges faced for an institutional transformation towards water security?