DJB’s ‘City Of Lakes’ project: For 50 water bodies in the capital, a fresh lease of life by the year end

The Delhi Jal Board (DJB) project to revive lakes in the city is inching forward with around 50 water bodies set to be ‘rejuvenated’ by the end of the year. Of these 50, work on around 17 water bodies is nearly finished.

At Paschim Vihar, a Rs 10 crore project is under way to lay a 4-km long pipeline from the treatment plant at Keshavpuram to replenish the lake with treated water. Among the other projects, work on constructing a drain alongside the Bhalswa Lake to divert wastewater into an STP was recently approved. Work on the Roshanara Lake is likely to begin in the next 30 days, while at the 50-acre Tikri Khurd lake in North Delhi, pipelines are being laid from the STP at Narela to recharge the lake.

Rejuvenation includes a small water treatment system is connected to the water body, or pipelines are drawn from an existing sewage treatment plant (STP) near the water body, to ensure a perennial source of treated water that is of a quality fit for groundwater recharge. Additionally, landscaping and planting native trees is undertaken.

The DJB classifies ponds of around 1 to 1.5 acres as ‘water bodies’ and larger ones as lakes. Lakes are being connected to existing treatment plants to ensure a source of water.

Some of the water bodies on the list are awaiting power connections for adjoining treatment systems. This system, which is a ‘natural’ STP in most cases, will draw wastewater from nearby areas, treat it, and feed it into the water body. A natural STP is a sedimentation tank combined with a constructed wetland that can remove pollutants. Floating rafters with an aeration system are used in some cases to treat the water.

This ‘city of lakes’ project was launched in 2018 to augment water supply by recharging ground water and recycling treated wastewater with the intention of meeting the city’s water demand of 1,140 million gallons (MGD) per day. The current supply of 940 MGD falls short of the demand by 200 MGD. Setting up new groundwater recharge reservoirs and rejuvenating existing lakes was the crux of the plan.

For 155 water bodies, the DJB has allocated a sum of Rs 376 crore, followed by around Rs 200 crore for another 90 water bodies, officials associated with the project said.

Lakes, including the ones at Rohini and Timarpur, have separate allocations of around Rs 64 crore each, while around Rs 10 crore has been allocated for the Bhalswa Lake.

While Delhi has over a 1,000 water bodies, only about 600 of these can be “revived” since the remaining have been built over or turned into parks. Of the 600, around 255 water bodies have been included under Phase I of the project.

Around 500 MGD of wastewater is being treated at 35 of the DJB’s STPs. This is set to go up to around 630 MGD by the end of the year with the small treatment plants that are being installed alongside water bodies.