Memoirs of an Immortal Marut

Mitigating Flood Risks in Kerala: Technological Solutions

Abstract

Kerala, a state located in the southern part of India and one of the most ecologically sensitive bio diversity hotspots in the world is facing multitudes of environmental crisis which are mostly man-made. Since floods hit the state in 2018 due to unprecedented high rainfalls, the state is witnessing large number of freak events of nature killing hundreds every year since then. However, with proper planning using space technologies, we can have systems in place like and integrated Dam management system and Landslide detection and prevention system. This essay explores the possibilities of using space technologies in mitigating such adversities.

In this endless, vast Universe, we humans are mere visitors. Like how a mother’s womb protects and nourishes her children, mother nature embraces us for the limited time we have as a visitor. Just like how a child is a part of his/her mother, we humans are part of this large ecosystem of Mother Nature, a small act of ignorance, a wrongful exploitation of nature can threaten the survival of this safe sphere of existence and we human beings would be the most affected. Today, we have reached a critical juncture where man-made actions have had adverse effects on the climate and our nature. Global warming, droughts, floods, collapsing of eco systems, species going extinct are all on the rise. Its high time we make a proper strategy to avoid, adapt and mitigate the ill effects of climate change. This Essay is based on a classic example of Climate change, a phenomenon that started emerging in 2018 and repeating annually, The Kerala Floods and Landslides.

Kerala, is a State located in the southern part of India. The entire land mass is a stretch of coastal plains wedged between the sea and the Western Ghats. The Western Ghats is one of the oldest land masses in the world and a part of the 36 global biodiversity hotspots. The UNESCO has recognised Western Ghats as one of the world’s eight hottest hotspots of biological diversity. As per a research paper published in ‘Environmental Research’, the carbon storage was highest in the species-rich western ghats, thereby providing an incomparable way to control Climate change. Kerala is famously known as ‘God’s own Land’ due to the scenic beauty and perfect temperature conditions for Human beings. The landmass is blessed with abundant rainfall that comes with the South-West Monsoon which is caused by the Western Ghats.

However, in the year of 2018, unusually high levels of rainfall were recorded. This had led to massive floods and widespread damage across the state. Over 483 deaths were reported and millions of dollars’ worth infrastructure was destroyed. This was an abrupt shift from the normal Monsoon patterns. There are around 55 dams across Kerala. Almost all dams had their shutters closed till the end of July, 2018 because very low rainfall was recorded the entire year. This has led to the authorities wanting to keep the dams full because a drought was expected. However, on the beginning of August, extremely heavy rains occurred forcing all 34 dams to fully open all the shutters thereby deluging the subsequent path of rivers. In the subsequent two years, 2019 and 2020, similar events have occurred. The reason attributed to the changing patterns of Monsoon and its increasing unpredictability is attributed to increasing Global temperatures, especially above the Indian Ocean.

Using Advanced Scatterometer and Microwave Humidity Sounder, we could measure temperatures, humidity and wind speed above the Indian ocean Region and predict the monsoon changes at least 3 weeks prior. An integrated Dam management system has to be setup where mathematical models have to be developed on how much water is to be retained based on the expected rainfall. Using GNSS and SAR technologies, we can monitor the Dam motion. This would help in better decision making for an integrated dam management compared to traditional methods. Using SAR technologies, previous years’ flood path has to be mapped, encroachments in the path cleared and barriers created on the banks. Currently these dams are used mainly for hydropower purposes and not for flood control.

Kerala is one of the most ecologically fragile zones in the entire world. In the past, an eco-friendly human-nature interaction used to exist when every temple in the land had small pockets of sacred groves that kept the biodiversity intact and large tracts of rice paddy fields which acted as cushions in case of heavy rainfalls. However, over the course of time, there have been many encroachments upon ecologically sensitive areas. Paddy fields diminished drastically to the point of the state becoming a consumer state. Quarry mines blasted sensitive areas for rocks, forests converted to rubber plantations and the areas where the rivers used to flow normally in case of deluge, was encroached upon.

One of the major reasons for deaths during the deluge was Land Slides. During the heavy rainfall, there were widespread landslides across the most sensitive districts. The highly unpredictable nature of Landslides made the job of rescue operators more difficult. Landslides became so widespread in Kerala due to a phenomenon called Soil Piping which occurred due to Kerala losing its soil texture due to massive quarrying. However, this can be predicted in advance using Space data.

We can use Ground Penetrating Radar technologies for spatial Mapping of Soil piping. After preparing the map, sinkholes can be filled with hard substances like rocks and even hard plastic and rubber waste materials apart from planting trees with deep roots. We can also use technologies such as synthetic aperture radar interferometry for monitoring the land slide prone areas and this technology has to be made available for local governments and disaster response team for taking quick decisions. Also, such technologies can be used by the Government for designating landslide prone regions in which no construction is to be made. It has been observed that Landslides occur when the soil moisture increases. Using Synthetic Aperture Radars, we could create Soil moisture Maps and this helps in identifying landslide prone areas.

There is no problem in the world that has no solution. With proper strategy and knowledge, all problems can be solved which includes Climate Change. Floods and Landslides are only part of a complex set of issues Kerala’s sensitive Geology faces. With the proper usage of Space technologies, a coordinated effort can be made in Mitigating these Climate change

induced environmental issues. If we do not sustain our environment, we cannot sustain ourselves. It is time to take action !