15-Water Quality Status of River Yamuna in Delhi Stretch

Abstract

River Yamuna, a major tributary of River Ganga, originates hear Yamunotri and confluence with Ganga River at Allahabad after travelling a distance of 1376 km. The Central Pollution Control Board is regularly monitoring water quality for entire Yamuna River stretch at 19 locations. The water quality characteristics of the river studied during the year 2003 reflect that the head and tail end of the Yamuna River was comparatively clean or less polluted than the middle stretch. However, the water quality of entire river stretch in terms of total coliform, which is an indicator of pathogenic bacteria is generally not confirming with the designated criteria. The Delhi stretch of river (22 km) between downstream of Wazirabad barrage to Okhla barrage is the most polluted stretch of Yamuna River. Though, the desired water quality of this stretch, based on designated best use classification is 'C' class (drinking water source with conventional treatment followed by disinfection), but the water quality in Delhi stretch of River Yamuna generally belong to D or E class (propagation of wildlife, fisheries and irrigation or industrial cooling and controlled waste disposals) during non-monsoon season. The water quality in this stretch is characterized by high bacterial and organic pollution load (BOD load) and strong disagreeable odour. All this create septic condition in the river. Masses of gaseous sludge rising from the bottom are frequently observed floating near the water surface. The reason of pollution in Delhi stretch of the river is the discharges of wastewater from domestic and industrial sources through 14 major drains from urban area of Delhi. Another reason of pollution in the river is over exploitation of fresh water from the river, which is essentially required to maintain self purification capacity of the river. The water quality of River Yamuna at Delhi stretch can be restored by strengthening of wastewater collection, transportation and treatment system. The use of treated water for irrigation purpose and regular release of fresh water from Wazirabad barrage in the river will provide instant improvement in water quality.