What Delhi Must Do To Rescue The Yamuna

Restoring the river's health will need correcting planning and execution flaws and pushing forward with circulatory water management. Blended green and social bonds can be used to fund this

- AK Jain

During the recent Delhi assembly elections, the polluted waters of the Yamuna became a campaign issue. The new government in the Capital must make river-cleaning a priority. While the immediate cleaning operations include trash skimming, weed harvesting and dredging, these will have to be long-term, overarching the entire region. The river zone in Delhi covers 9,934 hectares and the river flows along a length of 48 km. It is flanked by the river Hindon in the east and the Sahibi (Najafgarh drain) in the west. The Yamuna is integral to the Ganga riverine system. The river zone in Delhi has been used for power stations, samadhis, housing, offices, stadia, temples, cremation ground, an IT park, and illegal sand mining. More than 161 unauthorised colonies have come up in this zone which discharge their daily effluents and waste into the river. These have altered the river regime and endangered its water quality.

During the last 50 years, freshwater vertebrates in the river have declined by 83%, groundwater has depleted, and there is a serious loss of biodiversity. The embankments and construction have constricted the water flow, resulting in frequent flooding. With indiscriminate urbanisation, industries, unsewered colonies, fly ash and garbage dumping, the river has become a corridor of filth, garbage, squatting and insanitation.

About 90% of Yamuna water is diverted into drains and canals upstream, leaving it quite dry, especially during the summer. Without continuous flow, parts of the river become stagnant and highly polluted. Against the present environmental flow (e-flow) of 0.86 million cubic metre/day, the Yamuna in Delhi needs minimum 6.6 mcm/day. The Supreme Court, in 1999, directed that a minimum 10 cumecs of water be ensured throughout, together with pollution abatement and up-gradation of water quality to meet the burgeoning demand of water supply.