At first glance, this video of white foam floating on the surface of the Yamuna River in Delhi's ITO area appears almost serene.
A regular visitor and ominous indicator of water pollution, this toxic foam was last seen in November last year during the Chhath puja celebrations, when devotees stood knee-deep the toxic foam-laden Yamuna river.
In the video shared on Twitter by news agency ANI, the cloud-like foam is seen nearly completely covering the surface of the Yamuna river.
A wider shot of the river reveals that the foam extends to both banks of the river.
The hazardous foam occurs due to increased ammonia levels and high phosphate content in the Yamuna river, caused by the discharge of industrial pollutants including detergents into the river.
Last year, the Delhi government had deployed 15 boats to clear the toxic foam ahead of the Chhath puja celebrations.
Another technique used by the Delhi government in the past to dissipate the foam was to sprinkle water into the river.
The Yamuna has been the subject of concern for many years, and as recently as last month an official from the Delhi Jal Board said that the river has "almost dried up". According to the board, this would worsen the drinking water problem in the capital.
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