After much anticipation and a nine-year legal battle, Noida’s Supertech Twin Towers will be reduced to rubble on Sunday (August 28). The towers, Ceyane (29 storeys) and Apex (32 storeys), part of Supertech Ltd’s Emerald Court project, have been found to be in breach of several building regulations and are therefore being demolished.
The tallest structure in India to be demolished, the towers, comprising around 850 apartments and located in Sector 93A near the Noida-Greater Noida highway, stand nearly 100 meters tall – taller than the Qutub Minar. Preparations, from loading the buildings to clearing the area, are in full swing. The Residents Welfare Association (RWA) directed residents of nearby apartment complexes, ATS Greens Village and Emerald Court, must evacuate by Sunday morning. According to police, Emerald Court has 15 towers and ATS Village has approximately 25 towers and four villas.
The surrounding 500 meter radius area is marked as an exclusion zone, where no humans or animals will be allowed except members of the demolition team. Apart from this, police, a National Disaster Response Force team, eight ambulances and four firefighters will be deployed to the site.
Why are Noida’s Supertech Twin Towers being demolished?
Supertech received approval in 2005 from the New Okhla Industrial Development Authority (NOIDA) to build 14 towers of nine floors each, a shopping complex and a garden. However, he revised his project in 2009 to include twin high-rise buildings – Apex and Ceyane. Even though the NOIDA authority approved the new plan, the Emerald Court Owners Residents Welfare Association (RWA) moved to Allahabad High Court in 2012 alleging that it was an illegal construction.
In 2014, the High Court of Allahabad ruled that the towers were illegal and ordered their demolition. The Noida Authority and Supertech have approached the Supreme Court to challenge this order. On August 31, 2021, the Supreme Court upheld the decision of the Allahabad High Court and ordered the demolition of the buildings.
The Supreme Court ruled the construction of the Twin Towers in violation of the minimum distance requirement.
He said the towers were built without complying with building regulations and fire safety standards.
He said the change to the plan – removing the garden to make way for the construction of Apex and Ceyane – was carried out without the consent of the owners of the flat, which breached the Flats Act 2010. Uttar Pradesh.
The High Court, in August 2021, while ordering the demolition of the illegally constructed towers, said they were constructed by “acts of collusion between the leadership of NOIDA and the company”, and sanctioned the prosecution of officials for violation of Uttar Pradesh Industrial Zone Development Act 1976 and Uttar Pradesh Apartments Act 2010.
Although the court ordered the demolition within three months, multiple delays resulted in the establishment the deadline to August 28.
The demolition of Noida’s Supertech twin towers
Supertech towers will be demolished via a “controlled implosion”, meaning they will collapse after the explosives have been strategically placed and detonated to ensure minimal damage to the environment. The process behind the implosion includes the gradual weakening of the building’s critical supports, that is, the removal of structures that will help resist the gravitational force. This will be achieved by numerous explosives placed inside the structure. Usually, explosives on the lower floors of the structure trigger the controlled collapse of the building.
The technique was first used in 1773 to level Holy Trinity Cathedral in Waterford, Ireland with 68.04 kg of explosives. It was recently used in India during the 2020 demolition of four luxury waterfront apartments in front of Vembanad Lake in the Maradu of Kochi for violating Coastal Regulatory Area regulations. The same technique can also be used for the demolition of bridges, chimneys, towers, tunnels and other structures.
Mumbai-based Edifice Engineering has partnered with South Africa’s Jet, the same team behind the demolition of Maradu buildings, to demolish the Supertech towers.
One of the longest processes in a controlled implosion is the preparation to place the chemicals. For this demolition, the preparation took nearly seven months, including one month of planning and six months of on-site preparations, said Utkarsh Mehta, CEO of Edifice Engineering.
About 3,700 kg of explosives were infused in both towers. Apex has 11 primary blast floors, where all columns in the ground contain explosives, and seven secondary floors, where 60% of the columns will be blasted. Ceyane has 10 primary sanding floors.
According to Mehta, the main component used for blasting is emulsion which has superior rock crushing quality, typically used underground for heavy blasting and mining. He said they used a lesser amount of it in Supertech because the structures don’t require a lot. Besides the emulsion, shock tubes which will direct the blast waves and simulate real explosions, as well as electric and non-electric detonators which will trigger the explosives, are also used.
The event, which takes about 13 secondswill leave behind approximately 80,000 tonnes of construction and demolition waste, of which 50,000 to 55,000 tonnes will be used to backfill the site and the rest will be sent to a construction and demolition plant for processing.
Demolition of the Supertech twin towers: impact, concerns
There are several concerns regarding the demolition of Noida Supertech Twin Towers. The first is the amount of dust demolition will generate.
The second is clearing the rubble, although officials have said the rubble will be cleared within three months.
Third, experts have raised concerns about windblown dust generated by the blast, which can linger in the air for weeks and cause health problems for people in the area. The Noida authority said it would provide tankers, sweepers and sanitation personnel to control the dust threat. Officials also promised air quality monitoring.
Emerald Court resident Gaurav Saxena is leaving Noida for Nainital on Saturday night with his 65-year-old mother as he worries about fine particles that may remain in the air. Saxena plans to return to his apartment on Monday, but says he and his neighbors hope the plastic sheeting placed to cover their windows and balconies will protect them. He also hopes the rainfall will bring some relief.
Mehta, meanwhile, said: “We expect the dust to clear in 10 minutes. When this happens, our team will inspect the site and check for any remaining explosives to be detonated. The deposition of dust depends on the direction of the wind and its strength.
The dust’s impact on Noida’s already poor air quality cannot be ruled out, said Verhaen Khanna, a Delhi-based environmental activist and co-founder of the New Delhi Nature Society. He said a more scientific method should be used to control dust other than water spraying.
Another concern is the vibrations and shock waves that a demolition of this magnitude can induce. Mehta says that several studies conducted by the company predict a vibration travel time of 20 to 34 mm/s. But, on the ground, there will be much less impact, he claims, because predictions are made without regard to the design of the explosion. “We call the design a cascading implosion. The last point of the building hits the ground six to seven seconds after the first point. So there is no sudden impact on the ground and the vibrations will be transmitted gradually,” he said.
Mehta said the company has assured neighboring companies that there will be no vibrations that could damage structures but could cause cracks. He also said officials would monitor vibrations during the process at various locations to assess the damage.
Residents will be allowed to return home on Sunday evening, a few hours after the demolition.