India, Jan. 29 -- With the flick of a switch, a gush of water rushes upward from deep underground with a resonant whoosh. Two decades ago, the water table in Bhanheda Khemchand village lay shallow, within reach. Today, Sompal Pundir, a 68-year-old farmer from this village in Nanauta Block, Saharanpur, drills deeper, chasing water as its reserves shrink. He wonders: how much deeper can I go before the village runs dry?

"Back in 1975-76, when irrigation options were limited, we grew coarse grains like millet, jowar (sorghum), bajra (pearl millet), maize, and urad (black gram), as they required less water. But over the last 20-25 years, with the availability of water through tube wells, we shifted to crops like sugarcane, paddy, and wheat b...