No decentralised STP in Delhi even after four years of green court order
New Delhi: More than four years after the National Green Tribunal (NGT) directed the Delhi government to set up 32 decentralised sewage treatment plants (STPs) in rural areas and unauthorised colonies across the city, not even a single unit has been installed, reveals a report submitted in the green court.
An NGT-appointed committee that submitted the report said the government has not even started the process of acquiring land for the project.
The committee has urged the court to ask the state government to re-examine the proposal, as by the time these projects are ready, the population of these areas will increase. The DJB, meanwhile, has said it is working on the projects and will have to see the report before they could comment on the same.
At present, sewage from these areas goes directly into the drains, ultimately polluting the river Yamuna. According to experts, the release of untreated sewage into the river system is a major source of pollution in the Yamuna.
“Untreated sewage is still being drained directly into the storm water drains that empty into the Yamuna. At present the flow of waste water even in decentralised STPs is less, as most of it flowing into open drains. To tackle the problem at hand, it is best to trap and treat sewage at the source. For this technologies such as phytroid could be used at small distances. These are more efficient as well as cost-effective,” said Professor S K Singh, department of civil and environmental engineering, Delhi Technological University (DTU).
“It needs to be considered whether the DJB should at all go in for 32 more decentralised STPs. It may be asked to consider other alternatives such as using phytroid technology or constructing wetlands in drains to provide in-situ treatment,” the report submitted by the two-member Yamuna pollution monitoring committee said.
These STPs were to come up in areas such as Burari, Chhattarpur, Kirari, Narela, Bawana, Kanjhawala, Badarpur and Mundka with an overall capacity of 158 million gallons per day (MGD), as per an action plan submitted by the Delhi Jal Board (DJB) to the NGT in 2017.
These STPs were also part of the DJB’s own Sewerage Master Plan2031.
“The areas where these STPs are proposed do not have any sewer network and there is no certainty that even when a sewer network comes up, individual households will take connections. No policy has been formulated to make it incumbent on households to take sewer connections,” the report said.
Besides, it said 14 decentralised STPs planned in Najafgarh (These are besides the 32, as some work has been done on these 14 so they haven’t included it in the same) too have been stuck in limbo for the last four years.
A senior DJB official, said, “Work on the STPs is under process. A detailed project report (DPR) for most of the 32 STPs is ready. (For some of these projects funding sources have been decided while for others process is on. Tenders are yet to be floated to allot work. )”
He added, out of the 14 plants in Najafgarh basisn, seven projects have been sanctioned as well as funds have been granted by the Central government for which work orders were given two years ago. However, a sewage flow study was ordered again, as it was found that the proposed capacity of the plants was much more than the flow of waste water. Work on these will start once the study is complete and project costs are revised.
However, DJB vice-chairman Dinsesh Mohaniya said, “I haven’t seen the report yet. I will be able to comment on the observations only when the report comes to me officially.”
In September 2017, Delhi chief minister Arvind Kejriwal had asked the DJB to come with a road map to decentralise STPs all over the city. These were intended to stop untreated sewage from going directly flowing into the drains and produce a large amount of recycled water that could be utilised for purposes other than drinking such as watering parks, schools and industrial complexes, among others.
The committee pointed out that even a number (at least 13) of existing centralised STPs are operating below their installed capacity despite having been commissioned almost a decade ago due to absence of sewer connections to individual households.
While Centralised STP caters to a larger population and drain network decentralised STPs cater to small areas with less number of drains connected to the treatment plant.
At present Delhi as a total of 41 STPs, out of which 33 are operational. The overall capacity of the existing STPs is 607 MGD.
The city produces720 MGD of sewage every day, of which 458.75 MGD is treated.