- Mind the gap: Why the decline of Harappan civilisation sent India's sewage system down the drain - How did a country home to the world's oldest sophisticated toilets became the ground for Bezwada Wilson's battle against manual scavenging? http://scroll.in/article/813120/mind-the-gap-why-the-decline-of-harappan-civilisation-sent-indias-sewage-system-down-the-drain 5 comments india