In its 2018 composite water management index report, the NITI Aayog had identified Delhi as one of the 21 Indian cities that will reach zero groundwater levels in the coming decade, affecting its population of 100 million. If the current situation of increasing population and limited water resources persists, not just water security in the national capital but also ambitious initiatives such as Jal Jeevan Mission (urban) will also be threatened. There is thus an urgent need for a revised and progressively rational plan to sustain the increasing water demand in the city.
As per National Water Research Center (NWRC), there is a current demand-supply deficit of 141 million gallons of water per day in the city, which is likely to increase by 17% in the coming decade. In this backdrop, the Delhi Development Authority (DDA), in its Master Plan for Delhi 2041 (MPD41) suggested a number of reforms in the physical infrastructure of the water sector in order to achieve the desired water sustainability. The refinements in the MPD41 are majorly associated with solutions for the increasing water demand of the city.
The draft master plan suggests the adoption of an Integrated Urban Water Management (IUWM) approach to provide ‘water-linked infrastructures’ in the urban water cycle. Under this, water supply, wastewater management, and stormwater drainage are interconnected. It essentially focuses on using non-traditional water resources such as recycled wastewater to lower the dependence on surface and ground water. With the current pollution levels of the river Yamuna and almost all lakes and reservoirs of the city, it has become important to adopt this approach to adjust to the current and expected water demand. Moreover, similar to the depletion of non-renewable resource, current usable water resources are also on the verge of ending, according to a detailed study by Jamia Millia Islamia in August 2020.
Due to lack of sewerage system in many parts of the city, wastewater is disposed off directly into water bodies leading to worsening of their water quality. To counter this, decentralized wastewater treatment is an important step which is yet to be put fully in action. Currently, 72% of the wastewater generated in Delhi is treated, but due to lack of proper connection mechanisms from the Sewage Treatment Plants (STPs) to potential users, its reuse is limited. It is therefore, essential to monitor and evaluate the generated and treated wastewater to estimate the quantum of wastewater that can potentially be used for non-productive household and/or industrial purposes.
In addition to household and industrial use, urban agriculture in Delhi is also an opportunity for reuse. While agriculture in Delhi is not as vast as the agriculture in other states with large rural areas, it still supports the livelihood of a large number of families. As per the reports from Central Ground Water Board (CGWB) and Environmental Information System (ENVIS) Center in the year 2020, the quantum of wastewater generated was more than that of the groundwater extracted for irrigation in the city. Therefore, using treated wastewater for irrigation can fully eliminate groundwater extraction for agriculture in Delhi.
Delhi has also been receiving a fair amount of rainwater, which brings us to rainwater harvesting. Similar to solarization of houses, and organizational and institutional buildings, it is now important to install rainwater harvesting at a brisk pace. Despite positive public perception, the high costs of rainwater harvesting systems keep more people from adopting them. Therefore, there is a need for policymakers to modify water-related schemes in this direction to provide stepping stones for water sustainability in the city.
To increase water use efficiency at a narrow scale, learnings from the Environmental Protection Agency (EPA) of the United States should be implemented. They highlight the use of water-saving equipment such as water-efficient bathroom sink faucets and accessories. These are believed to save approximately 30% water as compared to the standard usage. Their usage should be encouraged at household and organizational levels to cut down on water wastage.
Coming back to the master plan, it has already included a list of key performance indicators (KPIs) such as water pollution control, rejuvenation of water bodies, flood risk reduction, wastewater reuse, and groundwater augmentation. These will help measure the progress in achieving the targets set. Further, similar to the Delhi Jal Board’s (DJB) water audit initiative that involves installing water flow meters at the domestic level for accounting water usage and any associated issues, data digitization in all sub-sectors will help achieve near-real-time situational awareness and informed decision making.
In conclusion, water management plans and strategies at national and state levels will succeed with conceptualization, developmental motive, and operationalizing all the feasible measures in the water sector. Apart from proposed steps to improve water supply, the government should also stress on water demand management. This will not only improve the water index, but also help link various environmental sectors, so that sustainable development is achieved on the environmental, social, and economic fronts.