Bangalore, India’s tech capital, is partway through an ambitious campaign to build a water culture – the ‘Million Wells for Bengaluru’ campaign. Started by the Biome Environmental Trust in July 2015, it is expected to run until 2025. The aim is to restore the city’s groundwater table through an ancient technique while providing livelihoods to local traditional well diggers, called Mannu Vaddars, in Karnataka.

Bangalore,  one of the fastest growing cities in Asia, has no major river and long ago outgrew the nearest river, the Arkavathi. The Cauvery River brings the city 1,450 million litres of water a day, but at its closest point, it is 100km (63 miles) south of the city.