Recently, the river Yamuna witnessed toxic froth floating on its surface in Delhi
Why does frothing in rivers occur?
- High phosphate content: The primary reason behind the formation of the toxic foam was high phosphate content in the wastewater because of detergents used in dyeing industries, dhobi ghats and households
- Turbulence and churning: These detergents and other organic matter gets deposited in the riverbed when the river is flowing normally. When more water is released upstream, it falls from a height on reaching the Okhla Barrage, leading to turbulence and churning which causes froth
- Release of certain gases: For the frothing is the release of certain gases when a specific kind of bacteria becomes active in anaerobic conditions — when there is no or little oxygen is available.
What causes a foam?
The foam is likely the result of a mixture of washing detergent residue and other waste, whipped into a froth
Why does such a problem occur repeatedly?
The majority of the detergents in the country don’t have a certification by International Organisation for Standardisation (ISO), which has capped the concentration of phosphates in the chemical substance
Other river pollutants and their impact
- Other river pollutants are cyanide, zinc, lead, copper, cadmium and mercury.
- These substances may enter the water in such high concentrations that fish and other animals are killed immediately.