"What Is That?" Foamy Patches Floating Across Cheonggyecheon... The Unexpected Truth

Complaints were filed regarding foam floating in Cheonggyecheon Stream, but it turns out it wasn't due to pollution.

Recently, footage of white foam floating in various parts of Cheonggyecheon Stream was captured, prompting complaints raising concerns over water quality deterioration.

One citizen noted that foam kept floating from the upper to the middle reaches of the stream and asked why no action had been taken for days.

The Seoul Facilities Corporation explained that it was not caused by external pollutants, but rather a natural phenomenon that can occur during the change of seasons.

They explained that as large temperature differences cause aquatic plants and organic matter to decompose, natural surfactant components are produced. When mixed with the current and water drops, this creates stubborn white foam that does not easily dissipate.

Unlike detergent foam, naturally occurring foam lacks stickiness or odor and naturally disappears once water temperatures stabilize, according to the characteristics.

The Seoul Facilities Corporation stated that water quality measurements taken last month also showed that Cheonggyecheon Stream met the "Good" level criteria.

(Source: Seoul Facilities Corporation website)
※ Please note: This article was translated by AI and may contain errors.