A century-old problem to trace the water supply of a lost civilisation has led to research with direct policy impacts for farmers in India today.
Professor Sanjeev Gupta and colleagues from Imperial’s Department of Earth Science & Engineering investigated whether the Bronze-Age Indus civilisation – which existed in North-west India and Pakistan thousands of years ago – was sustained by water from ancient rivers in the Himalayas.
Working with a multinational team, they used satellite imagery and sediment samples from close to archaeological sites in NW India to unpick the mystery, revealing an ancient river in the region dried up long before Indus towns developed. Unlike other ancient civilizations which were sustained by large rivers, they found that for numerous Indus urban centres the primary water source was monsoonal rainfall.
During the course of the research, local farmers highlighted issues with falling levels of groundwater in the region. Thanks to the insights gained from their study of the geological past, the team won funding from the UK’s NERC and the Indian Government to study groundwater systems in the ‘breadbasket’ of India. Their analysis revealed dramatic evidence of how groundwater-fed agriculture is causing rapid large-scale groundwater depletion with major future implications for the livelihoods of farmers.
