New Delhi A Delhi Jal Board (DJB) official said ammonia, phosphate and Total Dissolved Solids (TDS) levels have risen in the Yamuna, which are far above their safety limits. The water supply in the national capital has been affected due to high levels of these pollutants, inadequate supply of raw water and dry rivers, the official said.
The ammonia content in the river has increased to two parts per million (ppm), which is over and above the safety limit of 0.5 ppm. This affected water supply in parts of Delhi on Friday and Saturday, with water treatment plants (WTPs) in Wazirabad, Chandrawal and Okhla running at capacity to treat polluted water with chlorine. “Treatment plants are blocked by DJB when ammonia concentration is high and it cannot be treated. This is what affects the water supply,” said a DJB spokesperson.
Ammonia levels in water are also harmful to aquatic life as they make it more alkaline. The recent discovery of a large number of dead fish in the Yamuna can also be linked to ammonia poisoning. “Since the availability of raw water is less, the ammonia level has increased. The level will come down with the onset of monsoon in Delhi.” The level of phosphate, a pollutant that is responsible for toxic white froth in the river, has also increased to 0.7 ppm from the safety limit of 0.1 ppm. A government official said. “We have identified new pollutants in Yamuna which should not be there. Phosphate levels should not exceed 0.1 ppm, but we are seeing them at 0.7 ppm at the moment.”
Phosphate is an ingredient used in many detergents. Domestic waste water, industrial waste, idol immersion, pesticide residues and untreated sewage are some of the sources of this pollutant in the river. Manoj Mishra, convenor of Yamuna Jiye Abhiyan, said, “Lakhs of unauthorized industries leaving waste in the river are the major cause of pollution.”
The TDS level in the river has also reached 600 ppm, indicating heavy pollution as compared to the regular level of around 100-150 ppm. ‘The recent cloudburst has resulted in a lot of sediment in the water leading to high levels of TDS. The water, once treated at WTP, will have normal levels of TDS,” said a DJB spokesperson.
Questions sent to the Delhi Pollution Control Committee (DPCC) and the Central Pollution Control Board (CPCB) on Friday remained unanswered.