India will carry out its biggest controlled demolition when two residential towers in a satellite city outside New Delhi are brought down on Sunday.
The 100-metre-tall Apex and Ceyane buildings, commonly called the Twin Towers, were built illegally more than a decade ago and about 3,700 kilograms of explosives will be used in their demolition.
The towers, built by Supertech, are in Noida City, about 25 kilometres south-east of New Delhi.
A ruling to demolish them was upheld in August last year by the country's Supreme Court.
The ruling followed complaints from Noida residents that the towers breached construction rules.
The building regulations for the New Okhla Industrial Development Area initially allowed a housing project of 14 10-storey towers to be built on the plot.
But in 2006 the building company leased another area.
Under the initial proposal, an area was to be set aside for a garden, but the later plan included two more towers — Apex, which has 32 floors, and Ceyane, which comprises 42 floors — that encroached on the open space.
The additional towers were built nine metres apart, instead of the mandatory distance of 50 metres, in breach of fire safety and open-space regulations.
Residents of the other towers also complained that the Twin Towers prevented sunlight and fresh air from getting into the area.
After failing to resolve the concerns, residents filed a plea with the Allahabad High Court in Uttar Pradesh in 2012, saying the towers were constructed on an area meant for a garden.
Two years later, the court issued orders for the towers to be demolished and buyers to have their investments refunded, with 14 per cent interest.
It was found that the building company colluded with officials at the Noida Authority, the regulatory body.
That year, the authority and Supertech took the case to the Supreme Court, claiming there was no breach of rules.
Buyers also contacted the court seeking a refund or an order to allow them to move to another residential project.
The court upheld the high court's ruling on the demolition and directed the building company to refund buyers, including the 12 per cent interest.
The company was also told to pay 20 million rupees ($250,385) to the residents’ welfare association at the complex.
The demolition date was initially set for August 21, but was delayed for a week to allow formalities to be completed.
Mumbai company Edifice Engineering has been contracted to carry out the demolition, which will be completed in about 10 seconds.
About 10,000 holes have been drilled in the towers to hold the 3,700 kilograms of explosives.
At least 100 workers will help with the demolition, which is expected to take place at 2.30pm local time on Sunday.
It is expected to create a cloud of dust 60 storeys high and will leave behind about 55,000 tonnes of debris, Noida Authority said.
Some of the debris will be kept in a pit in the basement areas of the twin towers.
The 7,000 families living in the towers, as well as the two nearby communities, have been told to leave their homes by Sunday morning.
Emergency services and about 500 police officers will be sent to the site, while water services will be stopped in the residential area.
Residents have also been asked to turn off the gas and any person or animal within 500 metres of the towers will be moved to safety.