KOCHI: While the Supreme Court’s order to demolish the four apartment complexes at Maradu was to punish the builders and its occupants for violating the Coastal Regulation Zone (CRZ) rules, if the order is implemented, it would cause an even bigger environmental damage, according to an environmental assessment report by IIT-Madras.
The report, titled ‘Environmental Assessment of Construction Buildings and their Demolition in the Coastal Regulation Zone (CRZ) of Maradu Municipality’, states that the demolition of a complex with 80 such apartments, with a remaining life of 50 years, would have the same negative impact as the removal of 1 sq km of mangroves, over the same period of time.
The method of demolition, if carried out, should be carefully decided in consultation with experts, though implosion by explosives seems most appropriate. Even so, it would be practically impossible to remove the foundation, especially with the 35m-deep cast-in-situ bored reinforced concrete piles expected under the buildings in Maradu.
This could also result in significant environmental impact, including air pollution caused by fine material over a radius of more than 1 km, noise pollution that can disturb the fauna and residents, and vibration that could damage buildings nearby and annoy its occupants.
The fine material and debris could even contaminate water bodies and set on the leaves of plants, stated the report. Further, proper planning is critical for managing the demolition waste. For apartment complexes, it can be estimated that demolition waste generated would be about 450 kg/sq m of carpet area, of which, about 65 per cent would be concrete and about 25 per cent would be brick and mortar. “If the concrete won’t be recycled, it would imply that the demolition of a building of 1,00,000 sq ft area would require about 0.1 hectare or 0.25 acres of land for the debris to be piled up, as a layer of 3m,” it stated.
To avoid such an environmental hazard, it is essential to plan and implement a demolition waste management system for Maradu, which will require significant amounts to be allocated, in order to undertake the setting up of a recycling plant to produce aggregates for new concrete from the demolition waste. The cost estimated for a suitable plant (of 100 tonnes/hour capacity) to be operational would be about Rs 500/tonne of waste, stated the report.