How Delhi gets its water

• The Supreme Court directed the Himachal Pradesh government to release 137 cusecs of water it has in surplus, to resolve the drinking water crisis in Delhi.
• It asked Haryana to do the needful to facilitate the water’s flow into the national capital.
• Delhi Government blamed Haryana for “stopping” Yamuna’s water supply to the national capital.

Where does Delhi’s water come from?

• Delhi gets most of its water from the Yamuna, Ravi-Beas, and Ganga rivers.
• From the Ganga, via the Upper Ganga Canal in UP, Delhi receives 470 cusecs of water.
• Two channels entering Delhi from Haryana - supply Delhi with water from the Yamuna and Ravi-Beas rivers.
• The Delhi Jal Board (DJB) also takes water directly from the Yamuna to try and meet demand. Put together, Yamuna water - through provides a supply of 612 MGD to Delhi.
• Finally, the DJB supplements its river-water supply with ground water - around 135 MGD of which are drawn from Delhi’s tubewells and ranney wells.

Delhi’s water shortage:

• The water treatment plant in North Delhi’s Wazirabad was functioning below its capacity
• Coincidentally, this was the time when the national capital experienced record high temperatures, and thus, a steep surge in demand for water.
• But even at full capacity, DJB is not capable of meeting the city’s requirement of 1290 MGD during peak summers, as estimated by the Economic Survey for 2023-24.

Wazirabad WTP functioning below capacity:

• Across the states of Himachal Pradesh, Punjab, Haryana, and Delhi recorded large rainfall deficits in May.
• Scant rainfall meant that the Yamuna simply did not have enough water for the DJB to draw from the Wazirabad reservoir.
• Against a ‘normal’ level of 674.5 feet, the water level at the reservoir fell below 670.3 feet.
• Apart from low rainfall, the water levels are also impacted due to losses in transit, due to seepage, as well as due to evaporation.
• Of the 352 cusecs of water released from Haryana's Hathnikund barrage in the summers, a decent proportion is lost in transit.

How much water is Delhi allotted from the Yamuna?

• A water sharing agreement on the ‘surface flow’ of the Yamuna among Haryana, Uttar Pradesh, Rajasthan, Himachal Pradesh and Delhi in 1994:
  • specified that Delhi is to get 0.076 billion cubic meters of water from March to June.
  • This allocation is regulated by the Upper Yamuna River Board, with the 1994 agreement due for revision in 2025.
• In 1996, the Supreme Court ordered and directed that Delhi shall continue to get as much water for domestic use from Haryana through river Jamuna
  • which can be consumed and filled in the two water reservoirs and treatment plants at Wazirabad and Hyderpur.
  • Both the Wazirabad and Hyderpur reservoirs shall remain full to their capacity from the water supplied by Haryana through river Jamuna.”