DNA Explainer: Know what is ‘Waterfall Implosion’, technique applied to demolish Noida twin towers safely

With the countdown for demolition of the Supertech twin towers in Noida having begun, final checks are underway. The towers need to be razed to the ground safely. This means ensuring minimum damage to nearby buildings that house 5,000 people, which are barely 9 metres away. The answer of the demolition experts to this extremely precision destruction job is a technique known as ‘waterfall implosion’. 

The waterfall technique means that the debri will literally fall like water. Implosion is the method used for such urban demolitions which need controlled detonations. An explosion, on the contrary, would result in debris being flung far across directions.

Another analogy is how a ‘house of cards’ falls. The controlled explosions will bring down a massive 55,000 tonnes of debris in a matter of seconds while ensuring that the buildings literally sticking to the twin towers sustain no structural damage. 

The precision approach being used for Noida twin tower demolition

The technique was earlier seen in India when the same company demolished the 4 high rise buildings in Kochi back in 2020. The same method will bring the twin towers crumbling down in less than 15 seconds. 

The team is “150 percent confident” that the structures would come down to earth in the direction and in the precise manner that they have envisaged for the massive demolition. 

In implosion, a structure falls within itself. The technique uses the principles of gravity. It will remove the base of the structures in such a manner that the centre of gravity shifts by millimetres, bringing the structure down. 

“Gravity never sleeps. It works all day and all night. That's the whole idea of implosion,” an engineer of the demolition team was quoted as saying. 

“There is no book of reference for this method of demolition. There is no specific way of doing it or any word written anywhere in the world on how to do it. It's only on the acumen of individuals and their experiences of doing it,” he said. 

As part of the precision job 9,640 holes measuring 2.634 millimetre, exact to the last decimal digit, have been drilled in the building for the 3,700 kg explosives that will make it implode.   
Equipment like high and low speed cameras at multiple locations will capture the demolition for post-event analysis by the team. More than money, the team sees its reputation at stake with the massive feat at hand. 

Would the demolition cause any damage to nearby buildings?

The demolition team assures that there would be no structural damage. At the max, there would be some “cosmetic cracks” in paint and plasters or cracked windows where they have already weakened or become loose. 

Contractors have been lined up for carrying out repair jobs on the very day once the debris are clear. 

With final checks carried out on Saturday, the one remaining element of connecting both the buildings with each other and then connecting them with an exploder 100 metres away was carried out. 

The button will be pressed from the spot on Sunday at 2:30 am after police clearance. Arrangements are in place to clear dust in the aftermath with mechanical sweeping machines, anti-smog guns and water sprinklers deployed apart to aid sanitation workers.

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