The Assamese have had a love-hate relationship with the state’s rivers, writing songs and ballads about their role as nurturers and destroyers. Every year, they would stoically face floods. Now, though, floods seem to be becoming more frequent and intense, ravaging the state with increasing ferocity. This year, the town of Silchar in Barak valley faced the brunt and went underwater, leading to shortages of food and supplies.
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Isn’t it possible to be better prepared? To reduce loss of life and livelihood? A team of scientists in Delhi is working on impact-based flood forecasting that could help focus the relief effort. A drone startup, incubated at the Indian Institute of Technology, Guwahati, is highlighting just how useful unmanned aerial vehicles, or UAVs, can be in providing relief. And non-profits and locals are returning to indigenous wisdom to build houses.
Building a database, forecasting impact
Iss baar ke floods bohat ajeeb hain (the floods this time are very unusual),” an acquaintance from Guwahati messaged last week. “We are seeing newer afflicted areas, besides the usual ones.” According to a 29 June bulletin from the Assam State Disaster Management Authority, this year’s floods have impacted 28 out of 35 districts, 2,389 villages and 2,492,913 people. Silchar is one of the worst-affected areas. Some are calling these the worst floods in recent times. As flood frequency and intensity seem to be on the rise, there are calls for a better forecasting system.
Manabendra Saharia, an assistant professor in the department of civil engineering and Yardi School of Artificial Intelligence at the Indian Institute of Technology (IIT), Delhi, sees the cyclical devastation that plays out in his state every year. “Assam doesn’t have a statewide flood forecasting system. There are systems in place in cities like Mumbai and Chennai but not many in the cities or the hinterland of Assam,” says the 34-year-old, who is from Guwahati and runs the HydroSense research group at IIT, Delhi—it helps develop solutions for monitoring and mitigating natural hazards. One route is preventive action. “We know that floods will take place. This year, too, extreme rainfall was predicted by the India Meteorological Department (IMD). Using a sophisticated model, we should have been able to forecast which areas were likely to experience the worst floods,” he says. But there aren’t any impact-based forecasts that can gauge the difference in intensity of floods in, say, Dhemaji, as opposed to Nagaon.
“We may not be able to prevent the floods but we should be able to coordinate relief efforts better and beforehand. Every time, the state faces shortages of essential items, medicines and food. Impact-based forecasts should be able to solve this more efficiently,” says Saharia, who has also worked at the hydrology lab of US space agency Nasa’s Goddard Space Flight Centre and that country’s National Centre for Atmospheric Research. Such forecasts would also help develop a deeper understanding of the complex nature of floods, how climate change is impacting communities, and the best ways to integrate indigenous knowledge with technical solutions. Saharia believes India is capable of combining advanced, scientifically-designed warning solutions with proactive disaster management, as it does for cyclones and tsunamis.
His team and he are working with IMD on one such project. The Indian Space Research Organisation is funding this three-year, pan-India project, initiated last year, that will use satellite data and remote sensing observations to see hydrological extreme events on land such as floods and landslides. Together, they will develop an Indian Land Data Assimilation System (Ildas) that can incorporate a suite of hydrological models and satellite remote sensing observations. Within this, the Brahmaputra segment is a passion project for Saharia. He hopes Ildas will help plug some of the gaps in research and data generation.
The HydroSense team has also collaborated with IMD to create an “India Flood Inventory”, available in modern geospatial formats. IMD, which has been recording ground information since 1967, hopes to create a modern public database for disaster management. It’s not real-time, though, and they hope to rectify that.
Next on the list are improved modelling and flood forecasting as well as hazard and vulnerability studies. “Such data sets would help us in exploring the causes of the different types of floods in places like Assam and Bihar, and improve our understanding of atmospheric and geographic patterns that lead to such events,” says Saharia. The team/which has also released a tool? known as INDRA Reporter, through which citizen scientists can submit data on storms and floods based on local experiences. For data sets tend to be biased towards places where more people are working on the ground. “We are working with IMD scientists to set up a real-time data collection system nationwide which will help us to better track the ground-level impact of floods,” says Saharia.
Deploying drones to coordinate relief efforts
The view is clear but devastating. Army officers and rescue teams prep boats with boxes of essentials and medical items, preparing to traverse flood waters in Lower Assam. Following them, and surveying the submerged route ahead, are drones fitted with optical cameras. Some of these unmanned aerial vehicles (UAVs) also carry payloads, dropping medical and relief supplies in hard-to-reach areas.
These are drones operated by the Kolkata-based startup Drones Tech Lab, which was incubated at IIT, Guwahati. “It was around 17-18 June when we were contacted by IIT, Guwahati to keep our drones ready because they could be deployed at any moment,” says Debajit Deka, co-founder and head of operations at Drones Tech Lab, on the phone. “We brought down the drones from our Kolkata office and further developed them with the help of IIT so that they could carry and drop relief material. It was a very small window for us to work as we started operations on 20 June.”
Six-eight drones were deployed. For aerial surveys, they used high wind-resisting, multipurpose, long-range drones fitted with a 10x zoom camera payload. For dropping medical supplies and relief material, they used payload-ferrying UAVs that can transport weights of 5-10kg. They have a radial range of 5km.
The startup concentrated on Lower Assam, operating from areas like Balisatra where some land had not been submerged; this enabled aerial mapping and survey of the area within a 20km radius. “After the survey, we worked with government officials to target the areas that were worst affected with our payload-dropping drones. After three continuous days, we shifted our base to Hajo (north-west of Guwahati),” says Deka. Operating the drones was not easy, given the weather conditions and high wind speeds in open, submerged regions. Smaller drones would have drifted away, so they used the heavier UAVs. There were no provisions to charge batteries, so the team had to carry equipment for that too.
Disaster management services is one area the growing drone industry needs to focus on. Deka mentions a company that has come up with drones that can douse fires, carry small fire extinguishers and even a lifebuoy. In 2019, students at IIT, Madras developed an AI-based solution, Eye in the Sky, which would enable drones to gather information on people trapped in disaster-hit areas. Governments are yet to show interest, says Deka, but drones have the potential to revolutionise not just one sector, but all of them.”
But the use-case and benefits are there. “For instance, if the government looks at the activities we carried out, they can use these as an example to be much more prepared next time because floods are now becoming seasonal. Drones could be procured, deployed in the entire state if needed.”
The opportunities are ample, and so are the innovations. Recent advances in AI-enabled computer vision, swarm technologies, imaging and robotics, will only make drones smarter and more efficient in such situations. Technologies such as 5G and edge computing could eventually allow drones to process large amounts of data in real-time and help in search & rescue and post-disaster operations.
Back to the future with traditional housing
Manu Gupta, the co-founder of the Delhi-based Sustainable Environment and Ecological Development Society (SEEDS), remembers touring Assam in the late 1990s while working on a project on community resilience. There, he met a man who had built a home on stilts on the banks of a tributary of the Brahmaputra. Gupta was fascinated. “The four columns had hooks in them. Every time the flood waters rose, he would take off the flooring—almost like a tray—and place them at a higher level.” When Gupta asked the man why he said the floods were a good time to catch fish since his paddy was underwater and he couldn’t do anything else. “I thought it was a smart way to manage living with the risk of floods,” says Gupta.
This encounter influenced SEEDS’ housing reconstruction initiative in Assam after the 2017 floods. “We need more of these innovative solutions that people have self-learnt,” he says. Assam is not just vulnerable to floods, it also falls in an earthquake-prone zone. “Floods are an annual affair here,” says art conservator Avinibesh Sharma, pointing out that the problem became more acute after the 1950 earthquake, when the bed of the Brahmaputra rose and flooded low-lying areas like Dhemaji, Lakhimpur, and places in Lower Assam like Dhubri and Goalpara. Unplanned construction in places like Guwahati, especially in the catchment area, has made things worse, he says.
One solution, he believes, could be a return to traditional housing structures—Assam Type Housing, modified ikra houses which were developed by the British after the massive earthquake of 1897, and Chang ghars, or bungalows made on wooden stilts. Gupta mirrors his thoughts. The 80-odd housing units across Golaghat district built by SEEDS, in association with the North-East Affected Area Development Society (NEADS), after the 2017 floods draw inspiration from the traditional Chang ghars of the Mising tribe, which has always lived in low-lying areas and faced the risk of flooding. “They have the gift of good quality bamboo and the skill-sets on how to use it,” he remarks. “You can’t drive a nail so easily into bamboo; it will split vertically.” It needs other forms of joinery to bind it.
These homes amalgamated indigenous wisdom and modern technology. So far, the houses have survived the floods since. Unfortunately, though, bamboo houses are still seen as “kaccha”; the preference is for cement and brick and mortar.
In 2021, they constructed a flood-resilient shelter in Nikori village, also in the Golaghat district. This could be the way forward, says Gupta, since the frequency of floods is increasing and dislocating residents each time is disruptive.
Whether such shelters would be able to withstand the rising waters in years to come remains to be seen. There’s no escaping reality, though: Climate-adaptive designs must be adopted at a large-scale level. Even if emission targets on checking climate change are met, says Gupta, the world will continue to slide till 2060. The kind of projects currently in existence is, “very boutique," he says. "Unless we are able to make a difference at the policy, practice and supply chain level, we won’t be able to bring that transformation.”