Chile's Ministry of the Environment has declared the Aculeo Lagoon and its contributing streams as an urban wetland, covering 1,107.52 hectares in Paine commune. The move aims to protect the ecosystem from threats like drought and climate change, without banning recreational activities but regulating them for sustainable use. Paine Municipality, which requested the declaration, must now develop a plan balancing tourism, conservation, and local needs.
The Aculeo Lagoon, a symbol of climate change impacts in central Chile, dried up completely in 2018 due to a prolonged drought since 2010, worsened by irrational water extractions and diversions for agriculture and domestic use. Thanks to heavy rains in 2023 and 2024, the pluvial water body recovered, but it faces ongoing threats like unplanned real estate development, eutrophication from agricultural and tourist activities, waste dumps, racing tracks on its bed, aggregate extraction, and illegal land appropriation.
The Ministry of the Environment (MMA) resolution, dated December 18 and published in the Official Gazette on December 26, 2025, states: “Declare as Urban Wetland... the wetland named ‘Pintué Stream-Santa Marta Stream-Aculeo Lagoon’”. This declaration does not mean closing the area but ordering its rational use to sustain the basin, recharge aquifers, and maintain biodiversity. Recreational activities, such as water sports, must be compatible with ecosystem care, especially during sensitive periods for wildlife.
Paine Municipality, which requested the declaration, will develop a Municipal Ordinance for Urban Wetlands to manage waste, control fills, and define usage rules. Mayor Rodrigo Contreras welcomed the decision: “The declaration as an urban wetland is a tremendous opportunity for our commune to care for the lagoon... and also to boost and protect agriculture, which is the main source of employment in our commune”.
Environmentalists praised the measure. Greenpeace Chile's Silvana Espinosa noted that it “will provide greater protection to these water bodies, also delivering concrete tools to local governments for their defense”. UNESCO hydrologist Pablo García-Chevesich cautioned that “the declaration of protected wetland is a fundamental advance, but its effectiveness will depend... on evidence-based management, real extraction controls, and effective oversight”.
