Syllabus: 

GS3: Disaster and disaster management 

Context: 

Recently, researchers from IIT Delhi and IIT Gandhinagar have come up with a District Flood Severity Index (DFSI) accounting for the impact of the flooding events in all the districts of the country.

About District Flood Severity Index (DFSI) 

• DFSI is a comprehensive index that ranks districts by flood severity, based on both flood magnitude and its impact on people.
• This index is jointly developed by researchers from IIT Delhi and IIT Gandhinagar.
• It is developed for measuring district level flood severity as districts are the basic units of administration, planning and disaster management.
• The index uses the annual data collected by the Indian Meteorological Department (IMD) since 1967 along with district population to get a first-cut measure of how severe a flood is in an area.
• It is India's first significant attempt to chart a district-based, observation-driven measure of flood vulnerability and damage. 

Parameters of the DFSI

• DFSI uses six factors divided into two categories.
• Flood Magnitude Factors: It includes the mean duration in days of all flooding events in a district, the percentage of the area that is historically flooded and population in the district.
• Impact of Flood Factors: The total number of deaths and number of people injured.
• This index in its current form does not account for the aerial extent of agricultural fields that have been flooded.

Key Findings 

Top 5 Flood-Prone Districts by DFSI Score

• Patna (Bihar) - DFSI: 19.37
• Murshidabad (West Bengal) - DFSI: 19.01
• Thane (Maharashtra) - DFSI: 18.88
• North 24 Parganas (West Bengal) - DFSI: 18.86
• Guntur (Andhra Pradesh) - DFSI: 18.84

• Thiruvananthapuram district has faced over 231 flooding events, averaging more than four per year.

• Districts such as Lakhimpur, Dhemaji and Kamrup in Assam, and Gorakhpur and Ballia in Uttar Pradesh, also feature prominently, with some experiencing more than 200 flood events over five decades.

• Chamoli in Uttarakhand ranks in the top 30, highlighting the severe impact of rare but intense events like glacial lake outburst floods (GLOFs).

• The DFSI highlights the growing flood risks in urban centres such as Mumbai, Pune, and Nagpur, where rapid, unplanned development in low-lying zones has worsened the situation. 

• Additionally, coastal regions in states like Tamil Nadu, Gujarat, Andhra Pradesh, and West Bengal are increasingly vulnerable to both cyclones and intense rainfall events.

Need for DFSI

• Flood Prone Country: India is among the most flood-prone countries, with around 1.13 lakh flood-related deaths between 1975 and 2015, averaging 2,765 annually. Its dependence on the southwest monsoon, which delivers 75% of rainfall in just four months, heightens flood risk. 
• Districts are core units: Researchers emphasized the need for a district-level flood severity index since districts are the core units for administration and flood management in India.
• Reporting limitations: The study uses annual data from the IMD since 1967, mainly covering major riverine floods. Smaller floods or urban events may be missed due to reporting limitations.
• Lucania in existing flood indices: Existing flood indices mainly focus on flood magnitude or inundation, without capturing their actual impact on people.

Source: 

https://www.thehindu.com/news/national/a-new-district-flood-severity-index-factors-in-flood-impact-on-people/article69889327.ece#:~:text=Researchers%20from%20IIT%20Delhi%20and,and%20the%20population%20in%20the https://www.etvbharat.com/en/!bharat/patna-tops-indias-flood-severity-index-assam-leads-in-flood-frequency-with-800-occurrences-in-six-decades-enn25070904048