The green court observed the phenomenon was not confined to Delhi but is also happening in UP and Haryana

The mushrooming of unauthorised colonies in the national capital has resulted in destruction of the Yamuna river and environmental pollution, the National Green Tribunal said on Wednesday.

The green panel said the growth of unauthorised colonies has been the bane of urban planning and has resulted in giving rise to a grave environmental situation.

"This phenomenon is not confined to Delhi but is also happening in UP and Haryana. The experience of the last 20 years shows how the unchecked expansion of unauthorised colonies has led to haphazard proliferation of vast habitations of populations bereft of roads, drainage or sewerage," a bench headed by NGT Chairperson Justice Adarsh Kumar Goel said.

The tribunal said apart from sewage all such households also carry out home-based activities many of which have been found to be hazardous and which exacerbate pollution in drains and river.

"No amount of Sewage Treatment Plants and professional management inputs, repair of drains and interception of sewage will result in making the Yamuna cleaner unless the most major among the causes of pollution are confronted. In a city of 20 million if over 7 million inhabitants of unauthorised colonies live without sewerage it will affect the environment of all citizens," the bench said.

Perusing the report filed by the monitoring committee comprising retired NGT expert member B S Sajwan and former Delhi chief secretary Shailaja Chandra, the bench noted that while the implementation of the Septage Management Regulations has to continue it will not address the basic problem.

It noted that the Delhi Jal Board has reported that sewer network has been extended from 255 unauthorised colonies in 2015 to 384 in 2019 and that work is in progress to extend sewer network to another 432 unauthorised colonies covering a population of 21.60 lakh.

"The monitoring committee has stated that while the coverage of sewer network has increased considerably during the last four years, it is a matter of concern that the individual household connectivity of sewer network is very low.

"On DJB's own admission, although entire East Delhi is sewered, only about 60 per cent households have taken sewer connections. In fact, there are colonies like West Jyoti Nagar Shahdara, which was notified as a sewered colony in 2015, for 1,446 active water connections, only 167 households (11.5 per cent) have taken the sewer connections," the tribunal said.

The NGT said that DJB's has not spelt out any policy measures or forceful steps that are envisaged to compel households in the sewered areas to take household connections.

The tribunal had earlier directed stakeholders to give specific schedule for cleaning the Yamuna, while noting that repeated timelines have not been adhered to in the last 30 years and pollution of the river was still continuing.