The wells that read the grass: how Maldhari herders find sweet water in Banni

Nabudo Halepotra and his neighbours in the Banni grasslands of Kachchh dig shallow pits into the beds of dried seasonal ponds and pull out water fit to drink, in a place where the groundwater is salt and the summer air reaches 50 degrees Celsius. The wells are called virdas. They are dug, shared and repaired collectively, and the knowledge of where to sink them has passed down through generations of herders.

The trick is physics that no one in Banni needed a textbook to learn. Rainwater soaking into a jheel bed does not mix with the saline groundwater beneath; it floats on top of it as a lens, lighter and separate. A virda taps that lens. The dense grass cover the diggers look for is the surface telling them the sweet water is there.

Everything that follows is governed by the same knowledge. Water is lifted by hand in a leather or rubber bucket, a kos, tipped into shallow channels cut across the surface, and run off to storage trenches and earthen troughs called awada where the cattle drink. It is drawn slowly and rationed, because pulling hard pulls the salt up into the lens and ruins the well. A single virda will give drinkable water for anything from twenty days to four months. Then it turns brackish, and it is left alone to recharge.

If there is no virda, our existence will be threatened. Our cattle will perish.

The words are a Maldhari woman's, from the village of Berdo. They are not rhetoric. Banni receives an average of 317 millimetres of rain a year, more than four fifths of it between June and September, and the variation from year to year is enormous. What falls in those months is what the herders live on for the rest.

What threatens the practice is not one thing but several arriving together. Rainfall has become harder to predict and temperatures keep climbing. Piped water reaches some hamlets, unreliably, which is enough to make younger residents doubt whether the digging is still worth learning. And the grassland itself is closing in: Prosopis juliflora, a thorny shrub, has spread until it covers most of Banni.

The Prosopis was not an accident. In 1961 the Gujarat Forest Department authorised planting it across 31,550 hectares along the boundary between Banni and the Great Rann, meaning to hold back the advancing salt marsh. In 1997 it covered about six percent of Banni. By 2015 it covered fifty-four. Charcoal burned from its wood now brings in cash, which pulls hands away from herding — a second kind of drift, quieter than the first.

The Maldharis — the name comes from the Gujarati mal, livestock, and dhari, keeper — have not been passive in this. Their breeders' association took a case to the National Green Tribunal over farmland encroaching on the grassland, and in May 2021 the tribunal ordered the encroachments removed and confirmed the community's forest rights over the land they graze. Their buffalo was registered as an official Indian breed in 2010.

But no title deed digs a virda. That still depends on someone walking a dry pond bed in the heat, looking at the grass, and knowing what it means.