Flood Management In India
Floods in India – Overview of the Major Problem
The below points share some important statistics regarding floods in India, to help one gauge the magnitude of the problem caused by frequent floods and help understand the priority that needs to be given to tackle the problem.
- Floods are the most lethal of natural disasters in India.Between 1980 and 2017, India experienced 235 floods, which led to 126,286 deaths and affected 1.93 billion people.
- The economic losses due to floods stood at a humongous $58.7 billion. Floods in India are also the costliest among disasters, accounting for around 68 per cent of economic losses caused by all disasters (Emergency Events Database).
- As per data given in the Rajya Sabha, in 2018; the economic losses suffered by India due to floods across the country, was at approximately Rs 95,000 crores and unfortunately 1,808 people lost their lives.
- Floods in India account for over 40 percent of the deaths out of all natural disasters. Empirical studies have also shown that flood damage has a negative impact on economic growth in the long run and considerably reduces female employment opportunities in the agricultural sector.
- In 1980, Rashtriya Barh Ayog (National Commission on Floods) assessed that the total flood-prone area of India is around 40 million hectares which is equivalent to 12 percent of the total area of India. The Working Group on Flood Control Programme set up by the Planning Commission for the Tenth Five Year Plan put this figure at 45.64 million ha. About 80 percent of this area, i.e. 32 million ha, could be provided with a reasonable degree of protection.
- According to the ministry of home affairs, around 1,153 people were killed due to floods and landslides in 14 Indian states till August 27, 2020. Around 17.3 million people have been adversely affected on account of upheavals that took place after floods. The major fatalities reported are in West Bengal, Maharashtra, Bihar, Gujarat, Assam, Madhya Pradesh, Kerala, Karnataka,Jammu and Kashmir, Chhattisgarh.
- Government data shows that between 1953 and 2011, on an average, floods claimed 1,653 lives every year and caused losses – including the house, public property and crop damage of Rs. 3,612 crores every year.
- Since 1947, in Assam, more than 1.25 lakh families have lost either their agricultural land or residential land due to floods.
Some of the major floods in India in the past decade are
- Patna (2019)
- Kerala in 2018 and 2019
- Chennai (2015)
- Kashmir (2014)
- Uttarakhand (2013)
Floods in India – Major Causes
- Inadequate capacity within the banks of the rivers to contain the high flows brought down from the upper catchments due to heavy rainfall.
- Encroachment of floodplains
- Synchronization of floods in the tributaries and its main rivers.
- Some parts of the country, mainly coastal areas of Orissa, Tamil Nadu, Andhra Pradesh, and West Bengal, experience cyclones, which are often accompanied by heavy rainfall leading to flooding.
- Unplanned growth of urban areas
- Flooding is accentuated by erosion and silting of the river beds, resulting in a reduction of the carrying capacity of river channels
Flood Management in India – Different Factors
Flood management in India is dependent on various factors associated with climate change which are listed below
- The frequency and intensity of floods
- Rise in sea levels
Floods in India – Different Agencies for Flood Control in India
- India Meteorological Department (IMD) – provides rainfall or cyclonic event forecast which is used by all the agencies for preparedness to deal with the floods.
- National Disaster Management Authority (NDMA) – The job of relief and rescue is carried out by the National Disaster Response Force (NDRF) with state counterparts. NDMA works under Prime Minister Office (PMO) – and National Institute of Disaster Management (NIDM) – works under the Union Ministry of Home Affairs (MHA).
- Central Water Commission (CWC) – The main job of CWC is to procure the data of hydrology at the national level – like river discharge measurement and water level in dams etc – to alert the states about any imminent or potential flood.
Floods – Broad Categories
- Coastal Floods
- Flash Floods
- Urban Floods
- River/Fluvial Floods
- Ponding/Pluvial Flooding
Floods in India – 4 Different Regions
- Central India and Deccan – this region is prone to sea level rise, severe coastal erosion, and tidal flooding caused by cyclones.
- The Ganges – in this region the impact of heavy rainfalls is augmented by earthquakes and unregulated sand mining, which destabilizes riverbeds.
- The Brahmaputra – incessant rainfall can be aggravated by landslides and earthquakes, disrupting the natural flow of the river.
- The Northwest – vary across the area’s diverse landscapes,in the agriculture-dominated Punjab, flooding may be more associated with inadequate drainage facilities in irrigated fields. In the Himalayas, flooding is mostly associated with cloudbursts and glacial lake outbursts
Flooding – Measures to Control or reduce Damages
- To prevent coastal flooding due to more powerful and frequent cyclones (result of climate changes), mangroves will act as a perfect natural bulwark to prevent flooding in coastal areas. Hence conservation of Mangroves from degradation and destruction is of paramount importance.
- Use of Intelligent flood warning systems like IFLOWS (integrated flood warning system).
- Structural measures such as embankments and dykes
- Nonstructural measures such as flood forecasting and community participation in flood risk management
- Strict implementation of building laws, demarcation of flood prone areas.
Urban Floods and Major Causes
With massive rise in population in major cities due to migration of people in search of better economic opportunities, has resulted in expansion of cities rapidly, and people in the position of power have put the planned expansion of cities into the backburner, without implementing any proper policies. The country has witnessed urban floodings, which is the result of such unbridled expansion. Some of the major urban floodings were witnessed in
- Patna (2019)
- Chennai (2015)
- Mumbai (2005)
There are a plethora of examples for urban flooding, but the above 3 floodings had caused too much damage to those cities and its dwellers.
Urban Flooding – Major Causes
Some of the major causes of urban flooding are
- Lack of proper drainage network in the cities.
- Dying water bodies
- Encroachment of water bodies like lakes, ponds for building infrastructure or waste disposal.
- Disposal of garbage without proper planning.
- Climate change has resulted in erratic and very heavy rainfalls.
- India’s Land policy has not helped in managing or controlling the recurrence of major floods in urban areas. The reason for poor land policy could be economic, social and political. The importance of proper land policy has been highlighted even by World Meteorological Organisation (WMO)
Recently Floods in Assam and other north-eastern states have caused devastation of life and property, which is an annual problem in the region. However, floods are not restricted to North-eastern India, rather it affects many other areas in the country.
Apart from natural factors like incessant and heavy rainfall during the monsoon, there are man-made factors that contribute to floods in India.
India is highly vulnerable, as most of its geographical area is prone to annual flooding. The high losses and damages due to floods show the poor adaptation and mitigation status of India and inadequacy in disaster management and preparedness.
Thus, there is a need for an Integrated flood management system.
Factors contributing to the increase in Floods
- Climate Change: According to the International Panel for Climate Change, the rainfall intensity, duration and frequency are going to increase in the future.
- Also, incidence of cyclonic circulations and cloud bursts that cause flash floods are increasing due to Climate change.
- Skewed Rainfall Pattern: 80% of the precipitation takes place in the monsoon months from June to September. During this time, the rivers bring heavy sediment load from the catchments.
- These, coupled with inadequate carrying capacity of the rivers and drainage congestion and erosion of river-banks are responsible for causing floods.
- Trans-National Rivers: The fact that some of the rivers (like Brahmaputra, many tributaries of Ganga) causing damage in India originate in neighboring countries, adds another complex dimension to the problem.
- Also, sudden change in topography from high mountains to plain areas, is also a reason for floods in northern India.
- Earthquakes: An Earthquake Disaster Risk Index (EDRI), prepared by the National Disaster Management Authority (NDMA), showed that about 56% area of India is vulnerable to moderate to major earthquakes.
- As many of the river basins in India lie in earthquake-prone areas, the course of the river is not stable and amounts to flooding.
- Unplanned Development: Unplanned development, encroachments in riparian zones, failure of flood control structures, unplanned reservoir operations, poor drainage infrastructure, deforestation, land use change and sedimentation in river beds are exacerbating floods.
- When rainfall is heavy, the river breaches the embankments and destroys habitations along the banks and on the sandbars.
- Urban Flooding: Flooding in the cities and the towns is a recent phenomenon caused by increasing incidence of heavy rainfall in a short period of time.
- The reason for this is indiscriminate encroachment of waterways and wetlands, inadequate capacity of drains and lack of maintenance of the drainage infrastructure.
- Apart from it, poor waste management is exacerbating the problem by blocking drains, canals and lakes, while ill-planned road projects are cutting off flood flows
- Neglect of Pre-Disaster Planning: History of flood management shows that focus of disaster management has largely been on post-flood recovery and relief.
- Many reservoirs and Hydro-electric plants do not have enough gauging stations for measurement of flood level, which is the principal component for flood prediction and forecast.
- Disaster Preparedness Plan: A comprehensive flood management plan is needed to include Disaster preparedness. This may require strengthening of the following:
- Flood Hotspot Mapping at local and regional scale.
- Management and regulation of riparian zones to prevent spilling and erosion.
- River flood modelling to prepare for incidences like reservoir breach and emergency water release from dams.
- Advanced techniques such as mapping based on satellite imagery and Geographic Information Systems will help in development of flood early warning systems.
- Integrated Approach: Steps need to be taken for watershed management through an integrated approach. Often these approaches involve both hard engineering solutions and ecologically sustainable soft solutions.
- Hard Solutions: It involves civil engineering construction such as dams, culverts and dykes, widening and deepening of river channels and diversion channels to store and divert water to increase the lag time of water reaching downstream.
- Ecological Soft Solutions: The solutions such as restoration and management of riparian zones, afforestation along the river channels which led to retention of rainwater and reduces the river discharge.
- An integrated approach to managing floods requires a sound understanding of the patterns that rivers such as the Ganga and its tributaries display during the monsoon.
- Prioritising Buffers, Flexibility and Adaptability: This includes reviewing safety criteria of dams and canals, re-building these with higher safety factors, creating new intermediate storages, and introducing dynamic reservoir management.
- Reducing Disaster Risk Reduction: There is a need for efficient implementation of Sendai Framework for Disaster Risk Reduction, this will reduce the vulnerability of any disaster.
- Focusing on Urban Flood Management: Keeping in view the fact that the problem of Urban Flooding is becoming more severe and losses are mounting every year.
- The subject of urban flooding needs exclusive attention and the proper implementation of NDMA guidelines on Urban Flooding 2016, is the need of the hour.
As floods cause major damage to life and property every year, it is time the central and the state governments prepare a long-term plan that goes beyond piecemeal measures like building embankments and dredging to control floods. Also, there is a need for an integrated basin management plan that brings all the river-basin sharing countries as well Indian states on board.