Demand for sand in urban India is 60mn metric tonnes per year: StudyUpdated: Nov 21, 2019 00:43 IST
A study by the Indian Institute of Technology-Bombay (IIT-B) has estimated that the annual demand for sand in urban India is 60 million metric tonnes. To put the amount in perspective, the national demand for sand stands at an average of 1kg per person per day in urban India, according to IIT-B.
The study is important against the backdrop of United Nations Environment Programme’s (UNEP) declaration in May that ranked India and China as the two top countries globally where illegal sand mining has become a major environmental problem. UNEP had assessed the rise in demand allows the sand mafia to thrive.
The findings, prepared by Professor Shyam Asolekar and his team from the environmental science and engineering departments at IIT-B, were presented by non-governmental organisation Awaaz Foundation at the International Conference on Wetlands and Migratory Waterbirds of the Asian Flyways in Lonavala on Wednesday.
“Extraction of sand from the seabed leads to pollution, flooding, lowering of water aquifers, beach erosion, destruction of ecological habitats and frequent droughts,” said Asolekar.
The research estimated the amount of urban solid waste generated by India in 2019 so far has been about 78 million metric tonnes, generated by close to 40 crore urban population, and also provides data on urban legacy waste over the past 38 years (presently locked in dumpsites scattered all over the country), which stands at approximately 1,200 million metric tonnes between 1981 and 2019 .
“We must systematically separate inert solids from the currently generated solid wastes in urban India as well as from the present stockpiles of legacy wastes (mounds of decade-old solid wastes lying at select areas) and convert them into ‘manufactured sands’,” said Asolekar.
“This is the first time any national research body has been able to quantify the demand for sand in the country. It is crucial for the central government to come up with a pan-India policy to make it core part of the nation’s development agenda,” said Sumaira Abdulali, convener, Awaaz Foundation. “Loss of sand is a direct threat for wetlands as it forms a critical ingredient of habitats for waterbirds and their overall ecosystem.”
China recorded the highest use of cement (which includes sand aggregates) in the world, at an estimated 2.4 billion tones followed by India at 270 million tonnes, UNEP’s study had found.
“Based on our research, I am convinced that the potential raw materials that could be converted into manufactured sand in India are copper slag, granulated blast furnace slag, wash-bottom ash, quarry dust, foundry sand, and spent fire bricks,” said Asolekar who had provided his opinion on alternatives for sand mining to the Bombay high court, based on Awaaz Foundation’s 2006 petition.
“Combined with illegal sand extraction and a massive stockpile of garbage in India, we have a solution staring us in the face where this garbage can be used as raw material to replace sand for construction through implementable government policies providing incentives to businesses. This can completely replace sand in a phased manner,” said Abdulali.
Asolekar and his team, including PhD and Masters students, studied and analysed historical data using mathematical models to come up with the present scenario. “We analyse historical data from government sources (hindcasting), developed trends witnessed between 1981 and 2019 [nowcasting], considered past and present policy decisions, and we are now in the process of coming up with projections for the future [forecasting]. The entire study is a workover eight years,” said Asolekar.