Water in Delhi
New Delhi is the third most populated city in the world, with a current population estimate of 32,941,308 people (World Population Review). The city has been experiencing one of the fastest urban expansions in the world and according to a 2018 UN report, it is anticipated to be the most populous city in the world by 2030 with about 39 million people. With this increase in population, there is also an increase in, the demand for water without any increase in the water supply.
Paired with this increase in demand is a decrease in supply. In India, the per capita water availability decreased from 5,000 m3 in 1947 to 1,500m3 in 2016, while the threshold at which a society is considered water stressed is 1,700m3 (Delhi Jal Board). India accounts for 16% of the world’s population but only has 4% of the world’s freshwater resources. Compared to other countries, it is also much more heavily extracting freshwater from its internal resources. In 2000 it withdrew about 48% of its internal freshwater resources, while the United States withdrew about 17% (World Bank).
Where’s your water from? addresses unsustainable practices related to water in New Delhi.
According to studies based on biophilia, people’s connection to nature influences their level of pro-environmental attitudes and behaviours or PEAB (Whitburn et al.). Where’s your water from? leverages that influence, with a narrower focus on the source of water rather than nature as a whole, to develop more sustainable attitudes, perceptions, and behaviours around people’s water use.
Overview of Supply
New Delhi’s primary water sources are the Ganga, the Yamuna, and groundwater. The DJB uses these sources to provide 900 million gallons per day (MGD) to the city. However, this supply is insufficient and there’s an estimated deficit of 112 MGD which is met through further, often illegal, groundwater extraction (Biswas and Gangwar).
Water Production Locations and Sources
Information from the Delhi Jal Board
Distribution of Water Usage
The Delhi Jal Board (DJB) —the municipal body in charge of collecting, cleaning and distributing water to residents— estimates that the city uses about 172 Litres per Capita Daily (LPCD) (Delhi Jal Board). However, the municipal board also recognises that the reality of that usage is much different. Lower-income households use as little as 20 LPCD, whereas wealthier neighbourhoods use up to 450 LPCD.
Groundwater
Delhi is a rapidly growing and urbanizing city. In fact, it has the highest rate of urbanization in the world, and it is expected to add 870,000 people to the city every year. By 2030, it is predicted to become the most populous city in the world with 39 million people (World Urbanization Prospects). As the city and population change, so does the actual land that contains it. The amount of built-up land (including buildings, concrete, paved roads etc.) has increased from 28% in 1991 to 66% in 2011. This also means that other land types like forests and agricultural land have significantly decreased in that time period.
So then, how does this relate to groundwater?
Whenever it rains, the rainwater falls to the earth and seeps down through the many layers of rocks and fills the spaces in between. In this manner, the groundwater table is recharged, and we’re able to extract groundwater using bore wells and pumps. For sustained continuous use of this resource, there needs to be a balance between the rate of replenishment and the rate of extraction.
Here’s where the hiccough arises. When rain falls on pavement and concrete, it does not soak into the ground and filter down into the water table. Instead, it slips off the slick surface and into our city’s drainage and sewage system; effectively being wasted. As our city has developed, there is more and more built-up land and less and less rainwater makes its way into the ground. The water table is not being recharged at a rate to keep up with our consumption.
Besides creating a deficit in water availability, another consequence is a phenomenon known as land subsidence. Remember, the groundwater fills the space between layers of the earth, but as that water is extracted and not re-filled, the ground begins to compact. The rocks begin to fall into themselves and the vertical height of the ground decreases (USGS), which is known as land subsidence. The Delhi NCR region is experiencing land subsidence in three areas – Kapashera, Faridabad, and Dwarka- at sinking rates of up to 11cm per year (Garg et al.).