The Indus Valley floods of 2010 affected more people than any other
catastrophe of the present century. The reason apparently suggest a
lack of information and hence preparedness to the scale of floods.
However, nature possesses in itself the potential evidence for use of
humanity to learn from its past. Indus Valley hosted one of the
world’s largest ancient civilization until 1900 BC for a millennium.
The causes of its decline are a mystery until present. We investigate
paleoclimatic evidence from the Indus river fan in the Arabian Sea. A
re-visit of laminated varves and their corresponding thickness to
heavier output of sediments in monsoon, suggests varying flood
frequency and intensity for the last 5000 years. We find that Indus
Valley experienced extreme floods around 1750 BC with the increased
frequency of 8 and 12 years compared to 39 years of frequency in
complete record of varves proxy. Failed flood mitigation may have
ultimately resulted in the decline of Indus Valley civilization.