Nearly a week after Cyclone Vardah rattled the city, bringing normal life to a halt for a few days, Chennai is still reeling from the aftershock of the powerful storm.

With powerful winds that blew up to the speed of 120 kmph, around one lakh trees were estimated to have have been uprooted across the city by the cyclone, causing a loss of almost one-fourth of the city’s foliage, reported The Hindu. Many of these trees fell on transmission lines, damaging them severely and cutting power supply to scores of residential areas.

Employees of Chennai’s city corporation and electricity board were seen hard at work throughout the week, clearing the streets of fallen trees and repairing electricity lines. But with frequent power cuts and sporadic phone and internet signals, the city is still on the long route to restoration.

A senior official of the Tamil Nadu Electricity Board said that their personnel have been working every hour to ensure that normalcy returns to the city as soon as possible. “We have restored power to over 80% of Chennai,” he said. “The rest is also get intermittent power. By Monday morning, the whole city would be covered.”

Slow business

For Senthil Kumar, who runs a tiffin business in East Tambaram in South Chennai, there was no power from Monday, when the cyclone stuck, till Saturday morning. “For three days after the cyclone, we couldn’t open our shop,” he said. “On Friday, we decided to get the food prepared outside and bring it here. We served dosas and idlis without chutney and only sambhar. We’ve lost a week’s business. But you can’t blame the government. They have done well to restore everything so quickly.”

Local businesses depending on internet and phone lines to receive orders were also deeply affected. Moremilaga, a hyperlocal startup that delivers homemade food to customers across the city, said that even though they did not receive their usual number of orders over phone and internet, they managed to surprise their regular customers with packets of food.

“Many of the people who we give food to are elderly people,” said Ragini Murali, who is in-charge of the start-up’s operations. “We felt really bad that we could not give them food for a day because they cannot cook on their own or buy from a store. They depend on our food and were very relieved when we delivered food even when they could not reach us.”

Business is slowly coming back to normal except that now Moremilaga is receiving only 20% of its orders through internet, whereas earlier it was 50%, said Viji Ganesh, the founder of the enterprise.

Maligai Kadai, an online grocery delivery business in Chennai, was shut from Monday through Wednesday. Satish Sundaram, founder of Maligai Kadai, said that the online store hardly received any orders this week because of internet problems across the city. But he said that even delivery of orders placed prior to the storm was a problem.

“We couldn’t do anything,” said Sundaram. “We had to postpone the delivery of orders placed on Sunday because many of our customers left the city immediately after the storm. In other cases, we could not reach our customers on phone to find out if their area was accessible. If the roads were blocked with fallen trees, we would have to come back all the way.”

Why no internet?

Five days after the storm, communication signals were still erratic. Airtel subscribers across the country received messages that the cyclone in Chennai had affected one of their undersea network cables which in turn might slow down internet speeds. Subscribers to BSNL, Vodafone and other telecommunication operators were also facing similar difficulties.

The reason for this slow speed, explained Udbhav Tiwari, a policy officer at The Centre for Internet and Society, was that operators were having to reroute their traffic to other undersea cables that travel using longer, convoluted routes.

“The data takes long to travel, since it does not travel efficiently enough,” he said. “So if you search for something on the internet, it will open only after a minute because the packet had to travel the other three-fourth of the world to reach you instead of the shortest route.”

Submarine Cable map by TeleGeography.

Undersea cables, Tiwari explained, are usually owned by a combination of telecom companies as well as companies whose sole job is to lay these cables and rent them to individuals who will run their traffic through them.

These companies map out a route decided by demand between certain key points, hire a ship that trawls the ocean sea floor and lays and maintains cables, he said.

For the entirety of Asia, the Singaporean and Japanese region are the main hubs for internet exchange, Tiwari said, since they are considered reliable and commercially viable.

“Undersea cables almost always end in big cites,“ Tiwari said, “because of the infrastructure required to operate them. On the eastern side of India, Chennai is one of the best places to set up an end point for an undersea cable since it is a metropolitan city and closer to hubs like Japan and Singapore.”

If one of these lines near Chennai are broken, he said, it is very likely that the data would slow down because they have to find alternative routes.

“A severe cyclone or tsunami definitely has the potential to disturb or snap these sea cables,” Tiwari said. “But if maintenance is not carried out on them regularly enough, they can break for far more mundane reasons such as high water pressure, rust, debris falling from other ships or even sea animals.”