New Delhi, Aug. 8 -- The pollution parameters of the Yamuna have either remained constant or seen a marginal dip in July compared to the previous month, according to the latest assessment, despite the onset of monsoon rains that typically help improve the environmental flow (e-flow) of the river. According to the Delhi Pollution Control Committee (DPCC) report, dated August 4, at the exit point of the river at Asgarpur, the faecal coliform level has dipped to 320,000 from 390,000 most probable number (MPN) units per 100ml. This indicator of sewage entering the river is still over 150 times over the Central Pollution Control Board (CPCB) limit of 2, 500 units. According to the report, seen by HT, of the seven locations assessed along the river stream, only Palla had parameters within acceptable limits at 2,100 - better than 2,800 in June. Even at Wazirabad, from where Delhi draws its drinking water, faecal coliform was 3,500 MPN/100ml - a decline from 4,300 last month. At Okhla barrage and ISBT bridge, the faecal coliform level has remained constant at 110,000 and 170,000 lakh units, respectively, in June and July. Dissolved oxygen (DO) levels were recorded at 4.2mg/L at Palla, 3.1 at Wazirabad, and zero in the rest of the river. DO, which should be higher than 5mg/L, refers to the concentration of free oxygen present in water and is considered one of an important indicator of river health. The levels were worse than June at Palla (4.8) and Wazirabad (3.9), while they remained consistent for the rest. Similarly, Biological Oxygen Demand (BOD), which should be less than 3mg/L, rise from 2mg/L at Palla and 4mg/L at Wazirabad to 44 and 58 mg/l at Okhla and Asgarpur respectively, the report showed. BOD is a measure of the amount of oxygen required by microorganisms to decompose organic matter present in water, should be less than 3mg/L. Officials said the sampling had been carried out on July 6. Bhim Singh Rawat, coordinator of SANDRP, said the report does not show improvement perhaps because sampling was carried out on July 6, when there was not much flow in the river. Meanwhile, the Yamuna's water level stabilised by Thursday night after rising by more than a metre over the previous day. At the Old Railway Bridge, the river soared to 203.55 metres at 11pm on Wednesday before gradually receding to 203.5 metres by 5 am Thursday. The water level at 10pm was 203.1m....