Explained: Increase in ammonia levels in Yamuna

News: Water supply was affected in parts of Delhi after a spike in Ammonia levels in the river Yamuna led to a temporary closure of two water treatment plants.



  • Ammonia(NH3): It is a colourless gas and is used as an industrial chemical in the production of fertilisers, plastics, synthetic fibres, dyes and other products.
  • Source: It occurs naturally in the environment from the breakdown of organic waste matter and may also find its way to ground and surface water sources through industrial effluents, contamination by sewage or through agricultural runoff.
  • Acceptable Limit: The acceptable maximum limit of ammonia in drinking water as per the Bureau of Indian Standards is 0.5 ppm.
  • Effects: If the concentration of ammonia in water is above 1 ppm it is toxic to fishes. In humans, long term ingestion of water having ammonia levels of 1 ppm or above may cause damage to internal organs.
  • Treatment:
    • Mixing of freshwater with ammonia polluted water.
    • Stringent implementation of guidelines against dumping harmful waste into the river.
    • Making sure untreated sewage does not enter the water.
    • Maintaining a sustainable minimum flow, called the ecological flow.
      • Ecological flow is the minimum amount of water that should flow throughout the river at all times to sustain underwater and estuarine ecosystems and human livelihoods and for self regulation.


Additional Facts:

  • Yamuna River: It is the second-largest tributary river of the Ganga and the longest tributary in India.It originates from the Yamunotri Glacier in Uttarakhand and merges with Ganga at Prayagraj.It flows through the states of Uttarakhand, Himachal Pradesh, Uttar Pradesh, Haryana and Delhi.