Massive reservoir found at Rakhigarhi is giving us more clues on Saraswati River

A reservoir unearthed last month in Haryana’s Rakhigarhi is not just a marvel of Harappan engineering but also advances evolving research on the Saraswati River.

Rakhigarhi: The team of archaeologists teamed up with village labourers and pulled out several fistfuls of silt from a 10×10 trench a few weeks ago. Their eyes widened and they let out a collective gasp. With trembling mud-streaked hands, they brushed away centuries of mud.

They had long suspected that there was a Harappan-era water storage system at the dig site in Haryana’s Rakhigarhi. But their discovery that day exceeded all expectations—a mammoth reservoir, second only to the one at Dholavira in Gujarat.

It was nothing short of a marvel of engineering. Rakhigarhi, one of the largest urban centres of the Harappan civilisation, which flourished between 2600 and 1900 BCE, spans 500 hectares—nearly twice the size of Mohenjodaro. Yet nothing of this scale has been uncovered here. The December 2024 excavation laid bare an intricate and sophisticated water management system. Until now, wells had been found in Mohenjadaro and Harappa.

“Rakhigarhi was excavated many times, but no information about a reservoir was found until now,” said Sanjay Manjul, joint director general of the Archaeological Survey of India (ASI) and excavation director at Rakhigarhi. “For the first time, a water storage area with a depth of about 3.5 to 4 feet has been revealed at Mound 3. The findings will help in understanding water management during the mature and late Harappan periods when rivers began drying, and people started storing water.”

The reservoir also advances evolving research on the River Saraswati among geologists and archaeologists. During the mature and late Harappan periods, the Drishadvati River (also known as the Chautang River), the main channel of the Saraswati, started to dry around 3000 BCE. The reservoir was likely a response to the thinning river. Remote sensing data confirms the presence of paleochannels from the dried Drishadvati just 400 metres from the Rakhigarhi dig.

Over the past two decades, archaeological discoveries have been consistently confirming the idea of a mighty Saraswati River, mentioned in the Rig Veda. Said to flow from the Himalayas to the Arabian Sea, the Saraswati eventually disappeared, leaving only traces. The Drishadvati is also mentioned in the Rig Veda as an important tributary of the Saraswati.

“Drishadvati is a Vedic river and was the only water source near Rakhigarhi,” said AR Chaudhri, professor at the Centre of Excellence for Research on Saraswati River at Kurukshetra University. “It is from the time of the Mahabharata.”

Manjul, who started excavating Rakhigarhi in 2022, said that the Drishadvati was once a lifeline for the region. The findings, he added, point to advanced techniques employed by the Harappans for water storage. Previously, the site had been excavated multiple times by archaeologists Suraj Bhan, Amarendra Nath, and Vasant Shinde. The discovery comes almost exactly 100 years after archaeologist Sir John Marshall identified the Indus Valley Civilisation in 1924.

“About 5,000 years ago, when the river started drying up, people needed to store water for their personal needs, including agriculture,” said Manjul. “These findings will give us an idea of the pattern of water management and how a society used to think.”