For years, the Mahul nallah in Wadala has carried tonnes of floating garbage through its murky waters before eventually emptying into the Arabian Sea. But this week, the neglected drain saw an unusual intervention: workers using cranes and floating platforms installed a 57-metre-long floating waste barrier designed to trap plastic and debris before it reaches the coastline.

Launched jointly by the Bharat Clean Rivers Foundation and the Brihanmumbai Municipal Corporation, the indigenous “Trash Catch” or “trash boom” works like a floating conveyor system, intercepting waste flowing through the drain and channeling it to one side for extraction.…