Cecilia Tortajada and Navarun Varma
GLOBAL WATER FORUM | December 1, 2023
Big floods are on the rise, and so is the impact they are having on a large portion of humanity. Our traditional response has been to build bigger infrastructure – dams and embankments. However, besides being too expensive, the size and frequency of major flooding events are overwhelming our physical infrastructure and often magnifying the impact of the flood events. Here, Cecilia Tortajada and Navarun Varma discuss flooding in the Indian state of Assam and why the ‘new normal’ of flooding demands a shift of policy paradigm from infrastructure development alone to disaster prevention and preparedness.
Floods are affecting millions of people worldwide. Between 2018 and 2020, they resulted in substantial economic losses of US$300 billion.
In Asia, in 2022, there were some 387 natural hazards and disasters including floods. They affected more than 185 million people, killing 30,000 people and costing more than US$223 billion.
India, despite being the world’s fifth-largest economy, faces the highest number of poor people exposed to flood risks because of changing rainfall patterns.
According to the World Meteorological Organization (WMO), in 2014, damages from a single flood in India were estimated at US$16.9 billion. Damages from floods were less in 2022, both in economic terms, estimated at US$4.2 million, and losses of live, calculated at 2,000 deaths. This shows that progress in reducing disaster risks has improved, but it is not enough given the uncertainties due to climate change.
It is now agreed that the rainfall during the Indian monsoon will increase due to climate change in the 21st century. It is considered that every degree of warming is likely to increase monsoon rainfall by 5%, worsening floods and their impacts.
The International Strategy for Disaster Reduction strongly suggests flood adaptation and mitigation measures, but challenges in their local implementation persist. Population density and geographical conditions are not the only reasons why people and infrastructure are affected by floods. Also responsible are urban sprawls; lack of mainstreaming disaster risk reduction into development; lack of understanding of complexity of social vulnerability; and poor information and communication sharing among government agencies and the public.
Flooding in Assam – the ‘new normal’
According to the WMO, for the 1971-2020 period, the Indian seasonal rainfall during the summer monsoon was an average 106% of its climatological normal for the country as a whole. This resulted in heavy precipitation that affected populations and economic activities countrywide.
In Assam, a state in northeastern India, recurring floods are now so usual that they have become the ‘new normal’ because the state experiences three or four great floods every year.
Assam has over 125 rivers, including the Brahmaputra River. The average annual flow of the River is estimated at 527 billion cubic metres (BCM) per year representing 20% of the total surface flow of India. The river is braided having multiple channels and when in flood is known as the “moving ocean” (figure 1). This accelerates the rate of riverbank erosion causing frequent devastation in the surrounding valley.
As a result, some 40% of Assam´s land is flood prone compared to 10% of the total areas of the country. However, with improved policies and advanced planning, floods should not result in disasters as has been the case for a long time.
Traditional embankments offer protection against low to medium floods but are inadequate against large floods when they may collapse or are overtopped, causing immense destruction. Embankments, as well as dams, have represented the traditional approach for flood control. However, more comprehensive responses are needed.
The intensifying and erratic rainfall patterns, changes in land use patterns, and morphology of rivers in Assam demand a shift of policy paradigm from infrastructure development alone to disaster prevention and preparedness. An integrated system of floodplain zoning, flood forecasting, improved warning systems, along with opportunities for social learning can offer better protection to vulnerable populations.
This includes awareness campaigns for the population about the risks of moving settlements close to the embankments. Rather than protecting the population, this reinforces their vulnerability to flood damage and losses.
Climate Bill in local government
As climate change continues to generate extreme events, the concept of climate change-induced displacement is gaining prominence.
The 2022 IPCC report predicts that climate change impacts will force nearly 143 million people to leave their homes, creating climate change refugees. Nevertheless, there is currently no international convention to protect these individuals or provide long-term support for their rehabilitation.
A Member of Parliament representing Assam (from the opposition party) introduced the Climate Migrants (Protection and Rehabilitation) Bill in the Parliament of India. This is a private member’s bill to protect people living in riverine islands who become homeless due to floods and forced to resettle in prohibited areas such as forest land or grazing areas.
While this bill is unlikely to be approved in the near future, it can set a precedent for promoting protection for affected populations in Assam, across India and globally. It should also prompt a debate on the role of the state in ‘climate retreat‘, or relocation of population in high-risk areas, instead of waiting for distress migration.
Flooding events are inherently complex in Assam Valley, owing to the inter-dependencies of society and basin-wide geomorphological changes in the Brahmaputra region. Such changes are becoming even more uncertain with impacts in downstream flows resulting from construction of hydropower projects.
Building resilience in such a fragile context will require a shift in the policy paradigm for disaster policies, coordination between national, state and local institutions, and integration of grey, green, blue, and digital infrastructure. Equally important, there needs to be an integration of local knowledge in decision-making.
We have to envision a flood-tolerant future for the sustainability of Northeast India and the entire Brahmaputra basin with enough mitigation and adaptation measures for people to be safe.
This article is the result of a research project funded by the University of Glasgow’s GCID Small Grants Fund with participation of a larger number of researchers.
Professor Cecilia Tortajada is Professor in practice on Environmental Innovation at the School of Social and Environmental Sustainability, University of Glasgow, UK. Dr Navarun Varma is Assistant Director of External Programmes and Senior Lecturer (Resident Fellow) at Residential College 4, National University of Singapore. Singapore.
This article was published by GLOBAL WATER FORUM, November 30, 2023.