Angostura dam, Chile

A contested dam that is leaving without accessible electricity the local Mapuche communities since its opening


The company Colbún (in partnership with ENEL/Endesa) promoted the construction of the Angostura dam in the late '90s in an atmosphere of transversal dissatisfaction among Mapuche Pehuenche communities in the Biobío region. Productive potential, tourism, and environment protection conciliated trough collaboration with affected communities lied at the premises in the argumentation by the project promoters. Something that seems not to be translated into reality nowadays. The local Mapuche Pehuenche and neighbouring communities complained [1] [2] [5] that the dam (with installed potential of 316MW) would inundate a sacred land of high ecological value and asked for its inclusion in the list of World Human Heritage. The Biobio region has long suffered destructive interventions, that include the other three hydroelectric projects Palmucho (32 MW), Ralco (690 MW), Pangue (467 MW).  The social movements that at once organized in objection to the reservoir ended up to be criminalized, delegitimized and annihilated trough police intervention, while communities were been resettled without proper consultation [1]. In 2014 the plant was inaugurated. By that time, the local population was paying the higher cost of electricity in the entire country, despite living next to the hydroelectric plant [3]. Most of the people adapted to live without electricity due to the impossibility to pay the costs. Just two years later the Chilean government approved a law with the aim of equalising the prices between major and minor urban centres [4]. As today, the entire area around the dam reservoir is promoted as a tourism attractor [6]

Basic Data
NameAngostura dam, Chile
SiteSanta Barbara y Quilaco
Accuracy of LocationHIGH local level
Source of Conflict
Type of Conflict (1st level)Water Management
Type of Conflict (2nd level)Water access rights and entitlements
Dams and water distribution conflicts
Establishment of reserves/national parks
Specific CommoditiesWater
Tourism services
Project Details and Actors
Project Details"The project is situated approximately 600 km south of Santiago, in the municipality of Santa Barbara y Quilaco in the region of the Bío-Bío River 63 km south-east of the city of Los Angeles; downstream of the confluence of the Bío-Bío River with the Huequecura River, in the gully known as Angoustura del Piulo where the main intake starts.

The main civil works include the construction of an earth dam approximately 1.6 km long and 25 metres high on the left bank of the river and the construction of a Rollcrete dam 125 m long and 63 m high with a spillway incorporated along the Bío-Bío River.

The purpose of the project is the generation of electricity through a plant with an installed capacity of 316 MW, supplied by the reservoir of water formed by the two rivers; 1,542 Gwh of energy will be produced annually." [7]
Project Area (in hectares)650
Level of Investment (in USD)700,000,000
Type of PopulationSemi-urban
Company Names or State EnterprisesENEL Group (Enel) from Italy
Colbun from Chile
Salini Impregilo from Italy
Endesa Chile from Chile
Endesa (Endesa) from Spain
Relevant government actorsChilean Minister of Energy
Environmental justice organisations and other supportersEcosistemas,

Movimiento Aguas Libres sin represas,
The Conflict and the Mobilization
Intensity of Conflict (at highest level)MEDIUM (street protests, visible mobilization)
When did the mobilization beginIn REACTION to the implementation (during construction or operation)
Groups MobilizingIndigenous groups or traditional communities
Local ejos
Social movements
Local scientists/professionals
Fisher people
Forms of MobilizationBlockades
Development of a network/collective action
Development of alternative proposals
Media based activism/alternative media
Public campaigns
Street protest/marches
Arguments for the rights of mother nature
Environmental ImpactsVisible: Biodiversity loss (wildlife, agro-diversity), Global warming, Loss of landscape/aesthetic degradation, Deforestation and loss of vegetation cover, Surface water pollution / Decreasing water (physico-chemical, biological) quality, Reduced ecological / hydrological connectivity
Potential: Floods (river, coastal, mudflow)
Health ImpactsPotential: Mental problems including stress, depression and suicide
Socio-economic ImpactsVisible: Displacement, Loss of traditional knowledge/practices/cultures, Militarization and increased police presence, Land dispossession, Loss of landscape/sense of place
Potential: Loss of livelihood, Social problems (alcoholism, prostitution, etc..)
Project StatusIn operation
Pathways for conflict outcome / responseCriminalization of activists
Institutional changes
New legislation
Technical solutions to improve resource supply/quality/distribution
Violent targeting of activists
Development of AlternativesThe local NGO Ecosistemas suggested that the creation of ecotourism based activities would have been a good compromise between income generation, environmental value preservation and local culture conservancy [1]
Do you consider this as a success?No
Why? Explain briefly.Local communities were not involved in the process and were left without affordable electricity for the years following the inauguration of the dam.

After a persistent organised mobilisation of social movements, the Chilean government introduced a new law with the aim of equalising the prices between major and minor urban centres two years after the project completion [4].
Sources and Materials

Ley Nº 19.300, sobre Bases Generales del Medio Ambiente
[click to view]


[6] Angostura del Biobio
[click to view]

[3], 2014. Reportajes 24: la luz más cara de Chile. Accessed: 25/04/2017
[click to view]

[5] No al proyecto angostura. Accessed: 25/04/2017
[click to view]

[4], 2016. Alto Biobío verá reducida su tarifa eléctrica por 46%. Accessed: 25/04/2017
[click to view]

[1] Ecosistemas, 2014. Central Hidroeléctrica Angostura: La influencia del poder económico por sobre el Estado. Accessed: 25/04/2017
[click to view]

[2] Osses, S. 2014. Vecinos de Quilaco, Alto Bío Bío y Santa Bárbara protestan contra centrales hidroeléctricas. Accessed: 25/04/2017
[click to view]

[7] Salini Impregilo website. Angostura hydroelectric project. Accessed: 25/04/2017
[click to view]

Ecosistemas, 08/07/2014 - Angostura: El inicio de la primera gran hidroeléctrica en la última década
[click to view]

Media Links

Freddy Peréz, 2014. Central Hidroeléctrica Angostura, la influencia del poder económico por sobre el Estado. Youtube
[click to view]

TVN reportaje Hidroelectrica Angostura 07 01 17 HD
[click to view]

Other Documents

Angostura dam Credits:
[click to view]

Local communities protesting against the dam Credits: Sergio Osses,
[click to view]

Meta Information
ContributorAB - ICTA
Last update29/04/2017