Edited by Rohini
Design by Niharika
What comes to your mind when you hear about Chennai rains? It may be the relentless rainfall or the beautiful weather, depending on which side of the grass seems greener. IIT Madras has had its own share of heavy downpours, and there are countless stories about it. Whether it be the laughter upon seeing the condition of flooded OAT and SAC or the sheer stress of preventing your favorite clothes from getting spoilt by that sudden spell, many students have lived this experience.
Why are the rains so relentless in Chennai? In contrast to the rest of India, Chennai resides in a region that receives heavy rainfall from July to December, with November being the wettest month. Being a coastal city, Chennai is prone to heavy rainfall and cyclones throughout the year, leading to the city’s flooding. IIT Madras is no exception to this phenomenon and receives its own share of flooding each year.
Status of Water Infrastructure
In the city, rapid urbanization and the loss of wetlands and lakes have reduced the area where rainwater can collect. According to Care Earth Trust, a biodiversity research organization, Chennai has only 15% of its original wetlands1. Faulty storm drains filled with excessive silt and sewage add to the citizens’ woes. However, even after the 2015 floods, the Greater Chennai Corporation has been unable to transform the old drainage systems due to corruption and unscientific planning. Areas near IITM, like Velachery and Guindy, have next to non-existent drainage systems, which exert even more pressure on IITM infrastructure.
The lake inside the IIT Madras campus has a culvert to allow excess water to flow through, but the tunnel is restricted due to a nearby parking space. Along with this restriction, repeated silting of the lake every year has reduced its storage capacity. The improper disposal of garbage from the residential areas in Taramani into the drains and culverts has severely hindered stormwater flow out of the campus. The two maps below show the damage done to natural reservoirs by unplanned urbanisation near the Adyar river and Pallikaranai marshes.
On comparing the above two images, the loss of wetlands is evident . In 1960, the marshland had a size of 5500 hectares, which reduced to 600 hectares in 2013, a whopping 90% decrease in area. In addition, the presence of a large development project in the middle of the Pallikaranai Marshes has almost divided it into two halves, thus reducing its capacity even further. The Perungudi sewage treatment plant, which occupies 250 acres, is another threat to the marshland2.
Another example is the Adyar river. The floodplains clearly visible in the image from 2007 have been totally transformed into urban residential and commercial spaces. These areas are almost impossible to vacate and face flooding every year. Due to excessive garbage or sewage dumping, many flood buffers have been destroyed or are not usable.
Rain, rain, come again another day
The December 2015 floods in Chennai exposed the vulnerability of the IITM infrastructure. The floods led to the death of around 500 people in Chennai and over 18 lakh people were displaced, with damage and losses estimated between 200 billion and 1 trillion rupees4. IITM too faced its own share of problems. The semester was cut short and the institute placements and workshops were adversely affected3. There was a shortage of drinking water for a few days as well, with the power-cut causing a boost in candle and torch sales from Gurunath. Besides December 2015, we had the 2018 floods and the flooding this year in November. Low lying areas like the Student Activity Centre (SAC), faculty quarters, Velachery and Taramani Gates were inundated and unusable due to waterlogging. A 72-hour power cut was announced, along with the absence of cellphone connections for many students. The Open Air Theatre (OAT) was completely flooded, and SAC looked like an island. However, the institute quickly responded to the crisis by allocating fresh water and adequate food for the students. Pumps were used to extract the collected water, and the institute ensured that rains didn’t affect students’ daily lives. Thus, it was relatively safe for students to reside during such situations.
Along with SAC, two hostels worst affected were Sharavathi and Sarayu . The boys’ hostel benefited from the Sangam ground nearby, which allowed the water to pool there due to the presence of several ditches. However, the Sharavathi hostel has no way for the water to drain , causing the ground floor to get flooded during heavy rains. According to Chinmayi Gajula, the present HAS and ex-SLC Legislator, the makeshift solution is to pump water out of these hostels but the long run solution would be to ensure that the water drains off properly into the culvert. Students living on the ground floor had to be transferred to the upper floors for their safety. In 2018, Chinmayi Gajula, the then SLC legislator, raised the same issue in front of the council and formed an Ad-Hoc committee to look into this matter. The IITM Engineering Unit was taken in the loop, but no concrete solutions emerged.
Upon talking to a few students who witnessed the November 2021 flooding, it was revealed that compared to Chennai city, the institute fared much better in terms of flooding. Even with continuous daily rains, most areas of Insti remained relatively dry as water could flow out easily. However, for a few days, the area around Sharavathi hostel was flooded, and continuous rains caused walls of several rooms to leak, causing water to pool inside the rooms, which had to be mopped frequently. The mess menu was changed for a few days as the contractor couldn’t bring raw materials inside the mess due to the flooding of Taramani Gate. Online food delivery services were also disrupted for the same reason. Canteens like Usha were closed down, but Anjappar remained active. Food had to be delivered to the hostel directly for a couple of days due to continuous rains and flooding outside the hostel.
How is there no action to tackle the issue of flooding despite it being a yearly occurrence? Well, not much of it is actually in the administration’s hands. Before the city’s urbanization, Chennai was filled with lakes, which handled the excess water during cyclones and abnormal rainfall. However, all constructed areas created by filling up and destroying natural water bodies, like Velachery, Chromepet, Kundrathur, Porur, and Annanagar, are now prone to flooding because they are at a lower altitude and have a high groundwater level. The IITM Engineering Unit also stated that the groundwater level rises during floods, thus reducing the water-retaining capacity of the soil.
The Other Side of the Coin
Ironically, another conundrum that the city faces is the drought during the summer months, which occurs due to the lack of freshwater. As many natural water sources like aquifers, lakes, and marshes have been destroyed due to poor urban planning, there is a lot of urban runoff into the sea, causing the lack of freshwater. All three rivers flowing through Chennai have been polluted to such an extent that they aren’t fit for human consumption in any way. An extreme case of drought occurred in 2019 in Chennai, with alarming situations arising causing the GCC to bring in water tankers from hundreds of kilometres away to quench the city’s thirst. Day Zero was when all reservoirs ran dry in the city, causing violence and riots to rise in several neighbourhoods. People had to stand in long queues, and there were several instances of water tankers being hijacked.
However, there exist several possible solutions haven’t been fully implemented by the GCC. Runoff from storm drains could be diverted to these water bodies. Additional artificial water reservoirs could store the runoff water after the monsoon rains retreat fully. To tackle this water scarcity problem, the Chennai administration has constructed two water desalination plants, each with 100 MLD catering to both North and South Chennai5. In the past, the Tamil Nadu government had passed a law instructing all buildings in Chennai to build water harvesting systems. Although there was a temporary rise in groundwater level due to harvesting systems, it was soon eroded by lack of maintenance.
During the summer months, the Chennai metropolitan water supply and sewerage board (CMWSSB) cuts freshwater supply by around 50%. Nevertheless, IIT Madras has been able to tackle this problem successfully. The IITM campus has a freshwater lake that can hold around 180 million litres of freshwater, which receives the runoff during monsoon season, thus ensuring that most of the rainwater is stored. IITM also has a sewage treatment plant with 4 million litres per day (4 MLD). The sewage plant has been connected with the hostel, academic, and household zone with about 20 km long pipelines to ensure all wastewater inside the institute is treated. Prof. Ligy Philip, the institute chair professor for the Civil Engineering department, said, “We have a freshwater treatment plant near the lake which can supply 0.8 MLD for drinking purposes”.
IIT Madras is an integral part of the landscape of Chennai. Until Chennai fixes its water logging issues, we cannot expect the administration of IITM to be able to completely prevent the flooding of campus every year. Sustainable practices like controlled water usage, proper treatment, storage of excess runoff water, and efficient policies can remove both extreme sides of the floods and drought. Development of lakes and aquifers along with artificial rain water harvesting in all buildings can help store rain water during heavy rains and make them useful during the dry months when natural reservoirs start drying up. Until some concrete change occurs, you can just laugh your way through the rains and witness the (in)famous flooding in Chennai and IITM.
Sources:
1 Hindustan Times. (2021). Deep dive: Why does Chennai flood every time it rains heavily? [online] Available at: https://www.hindustantimes.com/india-news/deep-dive-why-does-chennai-flood-every-time-it-rains-heavily-101638297634345.html [Accessed 28 Dec. 2021].
2 Palanichamy, R.B. (2021). Why Chennai’s Flooding Problem Won’t Be Solved for Another 10 Years. [online] The Wire Science. Available at: https://science.thewire.in/environment/chennai-rains-flooding-problem-no-solution-10-years/ [Accessed 28 Dec. 2021].
3 Abheek, Dasgupta. “IIT Madras Got Its Fair Share of Woes during Chennai Floods: A Student’s Account.” The News Minute, December 11, 2015. https://www.thenewsminute.com/article/iit-madras-got-its-fair-share-woes-during-chennai-floods-students-account-36715.
4 How Many Lives Have Been Lost in Tamil Nadu Floods?”. The Quint. 12 December 2015. Retrieved 22 January 2016.
5 Lakshmi, K. (2012). Trial run at Nemmeli desalination plant soon. The Hindu. [online] 11 Oct. Available at: https://www.thehindu.com/news/cities/chennai/trial-run-at-nemmeli-desalination-plant-soon/article3985430.ece [Accessed 28 Dec. 2021]
