The Corfo Lagoon in Argentina has turned a bright shade of pink after becoming contaminated.
Waste from local fish farms is thought to have leaked into the water and caused a chemical reaction.
Fish farms use sodium sulfite to clean shrimp, which leaves a pink hue when present in water.
The reservoir has turned pink before but this is reportedly the most intense colour-change that locals have seen.
Federico Restrepo, a waterways treatment specialist, said the contamination was killing the chance of life surviving in the lagoon.
“It is worrying not only because it’s a case of pollution, in this case from the use of chemicals like sodium sulfite to avoid melanosis (oxide stains) on shrimps, but also from fats and oils,” he said.
“The BOD (biological oxygen demand) is… killing any kind of life that could be at the lagoons.”
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