- With the beginning of the monsoon season in June, pictures of floods in several parts of India have started coming up.
- Recently, Bihar, Andhra Pradesh, Kerala and Assam have witnessed floods fury. Also, cities like Hyderabad witnessed urban flooding leaving millions of people displaced.
- Thus, the flooding in India topic becomes relevant for the upcoming UPSC Mains examination 2022.
What are floods and their frequency in India?
- A flood is an overflow of water that submerges land which is usually meant to be dry. While it may occur along river banks, lakes and sea coasts, river flooding is the most common of all around the world.
- According to National Disaster Management Authority, NDMA, India is highly vulnerable to floods. Out of the total geographical area of 329 million hectares (mha), more than 40 mha is flood prone.
- On average every year, 75 lakh hectares of land is affected, 1600 lives are lost and the damage caused to crops, houses and public utilities is Rs.1805 crores due to floods.
Why floods are becoming a cause of concern?
- Large share in total annual disasters-The Asian Development Bank has estimated that floods are the most devastating among climate-related disasters in India. They account for more than 50 per cent of all climate-related disasters in the country.
- Increasing intensification– According to a study commissioned by the Asian Development Bank, Extreme precipitation and flooding cause large-scale impacts on people, and are further intensified by rapid urbanisation, infrastructure expansion, and large numbers of people residing in informal settlements in destitute conditions
- Causes huge destruction– An analysis by the DTE-CSE Data Centre of the Central Water Commission (CWC) data showed that in the last 65 years (1952-2018, Floods killed 109,412 people in the span. Over 258 million hectares of crops were damaged and 81,187,187 houses were raged. The total economic losses due to crop, house and other property damages came to Rs 4.69 trillion.
- Increasing financial losses– In November, 2019, the Union Minister of State for Jal Shakti, Ratan Lal Kataria told the Rajya Sabha that India suffered a loss of Rs 95,736 crore in the 2018 floods. This was 2.6 times more than the financial loss due to floods in 2017.
Causes of flooding in India
A) Man-made Reasons:
- Continued settlement in flood-prone areas: Floodplains of several rivers, especially in the northern plains like Kosi, Ghaghra, Gandak, Sarayu etc are flooded every year. Yet, these areas have been settled by people. This has led to recurring losses in the face of floods, especially in the Assam and Bihar plains.
- Encroachment over natural bodies: The destruction of natural wetlands including marshes and lakes has led to the blocking of areas that had earlier served as water sinks. This is the primary reason behind Chennai floods.
- Rapid and unplanned urbanisation: Construction of houses in a haphazard manner without getting plans approved has led to the washing away of several buildings during flash floods due to cloudbursts in the Himalayan region.
- Nature’s destruction: With increasing deforestation especially along coastal areas and river banks, the first line of defence against floods has been removed. This is the reason that cyclone caused floods result in severe destruction along the coasts.
B) Physiological Reasons:
- Heavy precipitation: Heavy rainfall is one of the major reasons for the flood in India. Over natural bank of rivers, the rainfall of about 15 cm or more in a single day exceeds the carrying capacity of rivers causes a flood in that region. Such effect can be seen in the West Coast region of the Western Ghat, Assam and sub-Himalayan West Bengal.
- Rise in river bed: The river bed rises due to large silt and sand gradients carried by the Himalayan Rivers. The deposition of silt enhances the catchment area of rivers which reduces the carrying capacity of rivers.
- The meandering tendency of river-flow: The tendency to meander or change the course within a specific boundary of rivers in the flat terrains also causes a flood in the meandering regions like the lower reaches of the Brahmaputra and Gangetic plains.
- Silting in Delta areas: The deposition of silt on the river-mouths by the sea tides deteriorates the discharging capacity of rivers which causes a flood in that region.
- Earthquake and Landslide: Sometimes it has been found that the river changes its course after natural calamities like earthquake, landslide which causes a flood in the same region. Such instances can found in the mountain of hilly region states like Jammu and Kashmir, Himachal Pradesh, and Uttarakhand etc.
- Obstruction of free-flow of rivers: Roads, embankments, railway lines, canals etc. obstruct the free flow of rivers leading to floods in the area.
- Cloudburst: Cloud bursts lead to a high amount of rainfall within a short time leading to flash floods. Flash flood generally occurs in the Himalayan region.
Consequences of Floods
- Financial Burden: while some flood-caused damages and losses are covered by insurance, others are not. Damages incurred due to natural disasters are usually not covered by insurance companies. It is important for landlords and property owners to check and enquire with their insurance agents about their plans and coverage for natural disasters. In some cases, state-wise aid is offered by the government to flood-affected people.
- Physical loss: the effects of floods are destructive for the property. Floodwaters can disrupt vegetation by destroying land due to shoreline erosion and soil stripping. Heavy flowing water can damage natural vegetation at its roots. It can contaminate water supplies, damage drainage systems, and farm crops.
- Emotional trauma: experiencing a wide range of emotions, flood-affected people often go through anxiety, fear, sadness, grief, and frustration during and after the disaster. Such conditions are often followed by symptoms like loss of sleep, loss of appetite, and mood swings.
Another cause of concern- Rising Urban Flooding
What are Urban Floods?
- Urban floods stem from a combination of various meteorological and hydrological extremes, such as extreme precipitation and flows in short periods.
- Thus, flooding in urban areas is caused by intense and/or prolonged rainfall, which overwhelms the capacity of the drainage system.
- It increases the flood peaks from 1.8 to 8 times and flood volumes by up to 6 times. Consequently, flooding occurs very quickly due to faster flow times.
Causes of urban floods
- Meteorological Factors: Heavy rainfall, cyclonic storms and thunderstorms cause water to flow quickly through paved urban areas and impound in low lying areas.
- Hydrological Factors: Overbank flow channel networks, the occurrence of high tides impeding the drainage in coastal cities.
- Climate Change: Climate change due to various anthropogenic events has led to extreme weather events.
- Population densities: Population density and proximity to urban centers significantly alter the dynamics and complexity when it comes to urban flooding.
- Unplanned Urbanization: This is the key cause of urban flooding. A major concern is the blocking of natural drainage pathways through construction activity and encroachment on catchment areas, riverbeds and lakebeds.
- Encroachment: Ideally, the natural drains should have been widened to accommodate the higher flows of stormwater. But on the contrary, there have been large-scale encroachments. Habitations started growing over them.
- Drainage System: Stormwater drainage systems in the past were designed for a rainfall intensity of 12 – 20 mm. These capacities have been getting very easily overwhelmed whenever rainfall of higher intensity has been experienced.
- Destruction of lakes: Lakes can store the excess water and regulate the flow of water. However, pollution of natural urban water bodies and converting them for development purposes has increased the risk of floods.
Flood management in India
- Federal working- The responsibility of flood management in India is divided between the Union and the State Governments with the Union Ministry of Agriculture being the central agency for coordination with states.
- Sharing of responsibilities: The role of the central government is technical and advisory in nature whereas the states are the actual implementers of the flood plans. Funds are also released by the centre to states in case of heavy flooding in any state.
Why flood management failing in India?
- New flood zones are coming up– such as drier areas of Gujarat, Rajasthan and in urban areas especially tier 1 cities like Chennai, Hyderabad. This is leading to the failure of previous flood zoning and estimates.
- Use of obsolete methods– like aerial surveys of flooded areas by PM, CM’s before releasing funds for flood management and use of decades-old flood zoning records.
- Fire fighting approach- the reaction to floods has been rather reactive than proactive. It is only after the flood has occurred that government machinery comes into action.
Possible Solutions to the flooding problem
- Improved flood warning systems: effective flood warning systems can help take timely action during natural calamities and can save lives. Pre-planning can significantly reduce the effects of floods, giving people time to migrate to safer locations and stock up essentials.
- Building flood-resilient housing systems: concreting floors can be very useful during floods. Houses should be water proofed and electric sockets should be placed at higher levels up the walls to reduce the chances of shocks.
- Constructing buildings above flood levels: buildings should be constructed a metre above from the ground to prevent flood damage and evacuation during floods.
- Resilience to Climate change: drastic climate changes have increased the frequency of natural disasters in many parts of the world. Governments should bring about environment-friendly policy level changes and eliminate the ones hazardous to the environment to tackle the problem of global warming.
- Create wetlands and encourage reforestation: creating more and more wetlands can help soak up excessive moisture since wetlands act as sponges. Wooded areas can also slow down heavy water flow, minimizing the effects of floods. Reforesting upstream regions can significantly reduce the effects of flood damage.
- Improve soil conditions: improper soil management, animal hooves, and machinery can make soil compacted. As a result, instead of holding water in and absorbing moisture, the water runs off immediately. Properly drained soil can absorb large amounts of rainwater and can prevent it from flowing into the rivers.
- Installing flood barriers: these are flood gates designed to prevent the area behind the barrier from flooding. They can also be kept around buildings to keep floodwaters outside the boundary created.
- Development of GIS– Geographical Information System (GIS) based National Database for disaster management. GIS is an effective tool for emergency responders to access information in terms of crucial parameters for disaster-affected areas.
- Developing a Federal flood management plan– with responsibilities of union and state clearly defined.
- Creation of 2nd flood commission– (Rashtriya Barh Aayog, created in 1976) to study the flood situation in India under rising challenges of climate change and propose a national-level flood resilience and management plan.
Some international models of flood management
- The Dutch Model of Flood Management– ‘Live with Water, Built with Nature’ sees cities as ‘waterscape’ and not ‘landscape’ as most of our cities are built along water bodies like river banks or coastal areas. The model proposes nature-based solutions for flood management in cities.
- Yongning River Park model– of china where artificial wetlands are created in and around cities to allow periodic flooding in these parks and act as a buffer for cities and thus preventing flooding.
Steps taken for flood management in India
- NDMA has released National level flood management guidelines.
- IN-FLOWS flood control systems have been installed in Chennai and Mumbai.
- National River Interlinking Project has been launched to control flooding and also to prevent droughts.
- Flood management And border area development program (FMBAP) has been launched of control of floods in border areas specially Bihar.
NITI Aayog’s Committee Recommendations on Flood Management
NITI Aayog in 2021 had constituted a committee on flood management under the chairmanship of Vice Chairman Rajiv Kumar which has suggested several measures like-
- Priority to non-structural measures: The committee held the view to provide priority to non-structural measures to mitigate the floods and shall go for long term and medium-term structural measures when and where those are unavoidable.
“In the majority of the places, less expensive non-structural measures like flood forecasting, flood plain zoning, flood proofing etc should be adopted to accommodate high spat of water,” the report said.
- Better dam management: The report also pitched for the policy to provide flood cushion in the existing dams to accommodate peak time flood so that the tragedy like the Kerala floods doesn’t repeat itself.
- Use of advanced technology: It stressed the use of advanced technology like artificial intelligence, satellites, remote sensing and GIS for flood forecasting and warning systems.
- Creation of a national water model– to feed information that can provide support services by predicting precipitation and forecasting.
- Creating a national body: Since flooding has been a recurring phenomenon across multiple states, the need is to create a national-level institution to promote cooperation among states and states and union.
- Developing resilience in people: The rapid transformation in rainfall characteristics and flooding patterns demands building people’s resilience.
- Reconsider projects: Construction projects that impede the movement of water and sediment across the floodplain must be reconsidered.
- Use of technology: At the same time, climate-imposed exigencies demand new paradigms of early-warning and response systems and securing livelihoods and economies.
With growing climate change impacts, flooding in India is also all set to increase in magnitude and intensity. Thus, the need of the hour is to adopt the Sendai framework’s Disaster risk resilience approach in flood management in India.
In doing so, India’s achievements in the successful management of the cyclone crisis in recent years, as recognized by the UN also, can be a torchbearer.