By the end of the first week of April 2017, the most current and reliable indicator for stored water in south India showed how dire the situation has become. And the South-West monsoon is still about eight weeks away. The weekly data sheet on the stored water quantities in the 91 major reservoirs of India, which is maintained and released by the Central Water Commission, has in the 6 April 2017 release shown the scale of the water emergency.

Of the 31 reservoirs in the southern region (Kerala, Tamil Nadu, Karnataka, Telengana and Andhra Pradesh) that are among the major reservoirs of India, 18 have stored water that is less than 15% of their full capacities.

These 18 are (ranked by least water stored):
Nagarjuna Sagar, APTG, 0.00%
Sholayar, TN, 0.00%
Almatti, KAR, 0.03%
Kabini, KAR, 2.25%
Vanivilas Sagar, KAR, 2.74%
Tungabhadra, KAR, 3.21%
Vaigai, TN, 4.07%
Parambikulam, TN, 5.00%
Malaprabha (Renuka), KAR, 5.56%
Hemavathy, KAR, 5.72%
Mettur (Stanley), TN, 6.72%
Periyar, KER, 6.94%
Bhadra, KAR, 9.02%
Lower Bhawani, TN, 9.09%
Srisailam, APTG, 9.44%
Krishnaraja Sagar, KAR, 11.44%
Malapmuzha, KER, 11.61%
Aliyar, TN, 14.74%
(TN is Tamil Nadu, KER is Kerala, KAR is Karnataka, APTG is Andhra Pradesh and Telengana)

Using a municipal average of about 400 litres per day per household that is a typical designed supply (not delivered, for that’s another tale), how much water does this allow for the 60.51 million households of the southern region until the monsoon begins?

Tamil Nadu has 18.46 million households, Kerala has 7.83 million, Karnataka has 13.3 million, Andhra Pradesh and Telengana have 20.92 million. These together need 24.2 billion litres a day or, in reservoir storage terms, 0.024 billion cubic metres (bcm) a day. The 31 major reservoirs of southern India together have, as of 6 April 2017, 6.583 bcm. From this quantity is taken water for industrial, agricultural and commercial use.

These uses are given priority or water stocks are secured (never mind allocation and metering) especially by industry. Normally, what remains for household use is about a third of the available stock. This leaves, as on 6 April, about 2.19 bcm for household use, which will suffice the 60.51 million households of south India for about 90 days – but only provided, and this is the stringent, non-negotiable condition that must be enforced, all households especially urban keep within the 400 litres per household per day limit.

The situation does not improve even if the monsoon arrives on time and the first weeks deliver normal rainfall. It is only by July 5-15 that reservoir water stocks begin trending upwards. This is where the 90-day restricted supply can take south India to. But only if immediate and strict rationing is imposed, as it should have been, to allow for climatological variance, by 1 March 2017.