Q.Flooding in urban areas is an emerging climate-induced disaster. Discuss the causes of this disaster. Mention the features of two such major floods in the last two decades in India. Describe the policies and frameworks in India that aim at tackling such floods.

Body Analysis

Urban flooding has emerged as a severe, climate-induced disaster in India. Driven by a combination of rapid, unplanned urbanization, climate-induced extreme weather events, and deteriorating municipal infrastructure, it leads to severe economic losses, disruption of critical services, and loss of human lives.

Causes of Urban Flooding

graph TD
    UF["Urban Flooding"] --> PDI["Poor Drainage Infrastructure"]
    UF --> UU["Unplanned Urbanization"]
    UF --> HRCC["Heavy Rainfall and Climate Change"]
    UF --> LGC["Loss of Green Cover"]
    UF --> CS["Concrete Surfaces"]
    UF --> EIC["Encroachment and Illegal Constructions"]

• Heavy Rainfall & Climate Change: Increased frequency of short-duration, high-intensity precipitation events. Example: In 2017, Mumbai recorded over 300 mm of rain within 24 hours, paralyzing the city.
• Unplanned Urbanization: Rapid expansion without corresponding drainage planning. Example: Bangalore's rapid growth in areas like Whitefield and Koramangala has severely outpaced its drainage capacity.
• Inadequate Drainage Infrastructure: Outdated, poorly designed, or unmaintained drainage networks. Example: The Chennai floods of 2015 highlighted deep structural bottlenecks in municipal storm drains.
• Encroachment on Natural Water Bodies: Construction on floodplains, wetlands, and natural drainage channels. Example: Encroachments along the Yamuna floodplains in Delhi block natural run-off pathways.
• Deforestation & Loss of Green Cover: Reduced natural vegetation decreases soil infiltration, accelerating surface run-off. Example: Deforestation around Hyderabad has led to frequent flash floods.
• Poor Waste Management: Plastic and solid waste clog municipal storm drains, preventing water flow during heavy downpours. Example: Clogged drains significantly aggravated the 2018 Kerala floods.

Features of Two Major Urban Floods in India

1. Mumbai Floods (2005)

• Extreme Precipitation: Received an unprecedented 944 mm of rainfall in a single 24-hour period in July 2005.
• Severe Casualties: Resulted in over 1,000 deaths and widespread waterborne disease outbreaks.
• Infrastructure Failure: The city's century-old drainage system, combined with high tides and the reclamation of the Mithi River, completely paralyzed transport and power networks.

2. Chennai Floods (2015)

• Unprecedented Rainfall: Over 1,200 mm of rain was recorded in November 2015, driven by a strong Northeast monsoon.
• Man-made Aggravation: Severe encroachment on wetlands (like Pallikaranai marsh) and natural drainage channels restricted run-off.
• Massive Displacement: Displaced hundreds of thousands of citizens, causing massive industrial and infrastructural losses.

Policies and Frameworks in India for Flood Management

• National Disaster Management Act, 2005: Established the NDMA, which formulates guidelines and coordinates national responses to disasters, including urban floods.
• National Policy on Disaster Management, 2009: Focuses on shifting the paradigm from reactive relief to proactive mitigation, risk reduction, and capacity building.
• NDMA Guidelines on Urban Flooding (2010): Specifically addresses urban flooding by recommending dedicated storm-water drainage designs, desilting protocols, and real-time flood forecasting.
• Flood Management and Border Areas Programme (FMBAP): Provides central assistance to states for flood control works and anti-erosion measures.
• Smart Cities Mission: Integrates climate-resilient infrastructure, smart drainage networks, and water-harvesting systems into urban planning.
• National Water Policy (2012): Advocates for the conservation of rivers, floodplains, and natural water bodies as natural flood-mitigation zones.