Algae explosion likely turned water pink, suffocated fish: Sentosa

A scenic canal had become a pink swamp as of Tuesday in the southern part of Sentosa Cove. Photo: The Heron of the Green Barrels/Facebook
A scenic canal had become a pink swamp as of Tuesday in the southern part of Sentosa Cove. Photo: The Heron of the Green Barrels/Facebook

It appears that the culprit behind Sentosa Cove’s fetid waters was Mother Nature herself.

An investigation into what killed hundreds of fish and turned the water pink in the Sentosa Cove neighborhood backed up speculation that persistent rain contributed to an algae bloom that deprived the water of oxygen, suffocating the fish.

The increase in the amount of nutrients and organic content likely led to the rapid growth of algae that turned the water pink, while the putrid stench was likely due to the decomposing fish which died after the algae gobbled up all the oxygen, the authorities said. 

“The findings suggest that the recent weeks’ heavy and persistent rainfall had altered the water conditions in Sentosa’s South Cove,”  the joint statement by the Sentosa Development Corporation and the National Environment Agency said. 

Tests found fish-unfriendly levels of salt and oxygen in the water.

“Particularly, tests on the water samples had found low levels of salinity and dissolved oxygen, which may have caused the fish kills, as well as a high level of nutrients,” it continued. “NEA has also assessed that the high nutrient level and organic content in the waters had in turn likely triggered the algal bloom, which changed the colour of the waters.”

Water activities in the area remain suspended until further notice while the upscale enclave’s management and authorities continue to monitor the situation. Sentosa said last week it had already begun to scoop up the stinky fish.

Residents in the area filled with seafront mansions first sounded off about the fouled pink waters online Tuesday with photos and videos online. 

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Clean up begins of fancy Sentosa enclave choking on dead fish, pink water

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