Waste water plan good, but Delhi must address treatment capacity
The Delhi Jal Board’s (DJB) decision to relaunch its amnesty scheme to regularise water supply in unauthorised colonies will help cork rampant pilferage of water and the consequent loss of revenue for DJB. The move will also help contain contamination of the water-supply and spell the end of the tanker mafia. The DJB had made various attempts to reduce pilferage of water from its lines, but a large number of illegal connections remain—almost half the water that DJB releases is lost to pilferage and leakage. The amnesty scheme, in its first avatar, had brought down the regularisation fee from Rs 18,644 to Rs 3,310. A similar incentive will likely be offered to draw people into the DJB revenue network.
But, the larger problem that DJB must contend with is the fact that demand for water in Delhi far outstrips its supply. While Delhi needs 1,200 million gallons per day (mgd), DJB has been able to supply only 860 mgd this summer, though it planned to release 916 mgd, as per The Indian Express. Against weak monsoons in some parts of Delhi so far—the Upper Yamuna River Basin saw a pre-monsoon deficit of nearly 40% this year—the problem is likely to get worse. Against such a backdrop, the DJB’s plan to improve water availability by 15-20% in the next couple of years—and 50% in the next five—by reclaiming waste water should contain the building crisis. The DJB plans to emulate Singapore’s NEWater model. The Singapore Public Utilities Board, since 2000, has been treating wastewater using microfiltration, reverse osmosis and UV treatment, in addition to the usual water treatment processes, delivering potable water that is purer than even the WHO purity standards for potable water. The DJB plans to start with treating 70 mgd of water, scaling up to 150 mgd by 2020. The treated sewage water will be pumped into the Yamuna at Palla, from where it will flow 11 km down the river’s course, “undergoing natural purification”, before it is collected and further treated at the Wazirabad treatment plant.
The only glitch, and by no means a small one, is Delhi’s disastrous track-record in treating sewage. Against a generation of over 1,000 mgd of sewage—and this was in 2015—Delhi has a treatment capacity of around 700 mgd. Chances are, not all of the capacity is utilised. This means a lot of the sewage generated by the city enters the Yamuna. Sewage treatment thus is a priority for the city. To be sure, Delhi does need a water reclamation plan. The groundwater level is already falling drastically in the city and a recent NITI Aayog report says that it may run out of groundwater in just the next two years. A just-released World Bank report also says that Delhi will be vulnerable to climate change effects, including rising water scarcity. To that end, DJB should move ahead with the plan—but, concurrently, it must address the city’s inadequate sewage treatment too.