About four months ago, Nandabhalan JK, a Class XI student at Chennai Public School, was confused about a waterlogging problem in Kolathur. His classmate and friend, Kharan PR lived in the area and it would flood even after the lightest of rains. The duo wanted to get to the bottom of the problem. They began their research and soon stumbled upon a startling fact. "Senthil Nagar, where Kharan resided, was part of Puzhal lake in the past but had been encroached upon later to make buildings and roads," says Nandabhalan. This made the duo wonder whether there were more such areas in and around the city that were born out of lake beds. With the help of the youth organisation, Ulagalaviya Ilanthamizhar Kuzhu, they, along with RB Rakshitha, a student of ABS Vidhya Mandhir, Thiruvallur, began mapping the lost lakes in the city.
The trio and their team have managed to map 97 lost lakes across Chennai, out of which 32 water bodies have completely vanished. But how are they mapping something that has vanished? Nandabhalan says, "We collect information from various libraries, including the Madras Literary Society, Connemara Public Library and PWD office. We also check British-era books on Madras and books written by S Muthiah and KRA Narasaiah." And that's not all. The students have also managed to leverage technology to ensure that the data they are collecting is stored properly. "We use Google's My Map feature and ISRO's Bhuvan app to map the data we have collected and also verify it," explains Nandabhalan.
The trio mostly does the groundwork for this project — visiting the sites, collecting information and speaking to people. "Other members of the team, which includes B Tamilselvi, E Sivakarthikayan, R Manohar, Padmalochni J, G Haritha and Sri Meenakshi J S, work on mapping the locations correctly on the current map," says Nandabhalan. Citing an example of a presence of a lake called Long Tank, Nandabhalan, adds, "This lake was found in British-era maps in 1908. The area is currently occupied by T Nagar. But that wasn't always the case. We have mapped it according to its longitude and latitude in the new map we are making."
For efficiency, the team has been further divided up into three groups. "The first team spots lost lakes from old maps, while the second team verifies it against the old books and archives. The third team works on the ground, talking to people about flooding in their area and so on," says Nandabhalan. Eventually, the team plans on publishing a book based on these lost lakes and also launch a website. "This will be the first book on Madras history published by school students," says Nandabhalan.
He and the team hope that through the map, some of the lakes can be saved. Moreover, they hope that it will be able to solve Chennai's water crisis. "Water tends to follow its old steam and through the map, the government should be able to identify which stream has been blocked by construction. Water can be diverted from that area into the present stream, preventing flooding," explains Nandabhalan. "Flood tunnels like those in Tokyo, Japan, can also be constructed with the help of this map to prevent excess water from entering the city. Instead, it can be stored solving the water crisis to a great extent," concludes a hopeful Nandabhalan.
