Data Centres And Water Scarcity

Vizag and Google’s data centres have been all over my feed this week.

Data centres in India use only about 0.02% of the country’s water. That figure is accurate. It is also useless, and both sides of this argument keep reaching for it.

One camp quotes it to end the conversation. The other answers with headlines about campuses drinking millions of litres a day. Both are national numbers, and water is not a national quantity.

India’s stage of groundwater extraction is 60.63%, which sounds comfortable. It is an average over 6,762 assessment units, and in 730 of them extraction already exceeds recharge. A data centre does not draw water from the average.

The supply side is no more uniform. Map the decadal rainfall trend by district for 2011 to 2024 and roughly a third of districts are drying while nearly half are getting significantly wetter. Neighbouring districts sit in opposite classes. There is no national trend to average.

You can wheel electricity. A facility in Maharashtra can buy wind from Gujarat, and CEEW’s work with SYSTEMIQ puts up to 80% renewable supply as feasible for these sites. You cannot wheel an aquifer. Every litre drawn in a stressed block is a litre a farmer in that block does not get, and no transmission line fixes that.

Here is the part I find more interesting than either talking point.

Two estimates published in India this year put a 100 MW facility at 800,000 litres a day and at 2 million. Same year, same size, 2.5 times apart. Neither is wrong. Cooling architecture and local wet-bulb temperature move the answer that much.

We are arguing hard about a quantity nobody in India is required to report.

The useful instrument does not tell states where they may not build. It says: this block supports X MW on closed-loop cooling, less on evaporative, more again on treated wastewater. That turns a yes or no fight into a design question, and design questions have answers.

Fifteen states have data centre policies. Five have sustainability provisions.

Where do you think this is wrong?

Data: rainfall trends from the Council on Energy, Environment and Water (CEEW)’s CRAVIS portal; data centre water and power figures from CEEW and SYSTEMIQ, 2026; groundwater from CGWB’s Dynamic Ground Water Resources Assessment 2025.