In a bid to become eco-friendly, the Mumbai Metropolitan Region Development Authority (MMRDA) is considering a proposal to recycle the construction and demolition waste generated during Metro work into construction material.
“The waste generated can be recycled into reusable raw materials for building activities. This will not only be environmentally beneficial but will also help us save costs,” said a senior MMRDA official.
With the construction of two metro corridors — Metro 2A and 7 — under way and four more likely to begin by the end of this year — Metro 2B, 4, 5 and 6 — an overall 1,61,080 cubic metres (cu m) of construction and demolition (C&D) waste is expected to be generated.
“According to clause no. 4 of Rules for Management of C&D Waste, 2016, regarding duties of the waste generator, it specifies that waste generators who generate more than 20 tonnes or more in one day or 300 tonnes per project in a month shall own the responsibility for managing the C&D waste,” reads the proposal.
“…it is observed that our Metro projects are generating C&D waste beyond the quantity specified in the said notification, it is mandatory for MMRDA to initiate the processing of C&D waste generated from our Mumbai Metro projects,” it further adds.
The proposal estimates that after recycling 1,61,080 cu m of C&D waste, at least 1,31442 metric tonnes of manufactured sand and 1,13,401 metric tonnes of recycled concrete aggregate will be generated. “This can either be used in the construction of our Metro projects or for the manufacturing of concrete or other materials. The waste can also be recycled into tiles and bricks,” added the senior official.
“According to the present sale value, the cost of manufactured sand, which is Rs 1,600 per metric tonne, will be at least Rs 21,03,06,550 whereas the cost of recycled concrete aggregate, at Rs 750 per metric tonne, will be Rs 8,50,50,443,” the proposal mentions.
Currently, the contractors are expected to dump the waste in landfills on the outskirts of the city. Apart from the cost benefit of Rs 29,53,56,994, cost of transporting the waste to these sites will also be saved. “We have instructed them to transport the waste to areas which are at least 25 km away. But due to the costs involved, this rarely happens and they dump it wherever they like including in mangrove areas,” he added.
But UPS Madan, Metropolitan Commissioner, MMRDA, said this plan will not be implemented immediately as the quantum of waste produced currently is not much. “Once we have more projects that require construction materials like coastal road then we can reuse the material there. Not much waste is being generated from the two corridors that are under construction,” he said.
Earlier, the Brihanmumbai Municipal Corporation (BMC)’s solid waste management department had also announced its plan to recycle at least 95 per cent of the construction waste generated in the city into building material. firstname.lastname@example.org