Cyclone & Flood Management — Set 11

Correct Answer: B. Retaining flood water during heavy rainfall to reduce downstream flooding

Flood cushions are designated portions of reservoir storage capacity that are kept empty before and during the monsoon season to retain excess floodwater, thereby reducing the volume of water released downstream. Proper management of flood cushions is critical for preventing dam-induced flooding. The Kerala floods of 2018 raised questions about whether flood cushions in Kerala's reservoirs were adequately maintained.

Correct Answer: C. Mumbai

Mumbai is most frequently cited as an example of chronic urban flooding due to its inadequate storm water drainage system, which dates back to the colonial era and has not been sufficiently upgraded to handle modern rainfall intensities. The July 26, 2005 cloudburst exposed the extreme vulnerability of Mumbai's drainage infrastructure. Despite various improvement projects, Mumbai continues to experience significant urban flooding each monsoon season.

Correct Answer: C. Tamil Nadu

Cyclone Gaja made landfall near Nagapattinam on the Tamil Nadu coast on November 16, 2018, as a Severe Cyclonic Storm. The cyclone caused significant damage to agricultural land, coconut plantations, and rural infrastructure in coastal Tamil Nadu. Large-scale evacuations were carried out before landfall, limiting the death toll despite the storm's destructive impact.

Correct Answer: B. Sustainable management of coastal areas including disaster risk reduction

The Integrated Coastal Zone Management (ICZM) project in India, supported by the World Bank, aims at the sustainable management of India's coastline including disaster risk reduction, conservation of coastal ecosystems, and regulation of development in sensitive coastal areas. ICZM recognizes that healthy coastal ecosystems including mangroves and coral reefs provide natural protection against cyclones and storm surges. It has been implemented in Odisha, Gujarat, and West Bengal.

Correct Answer: B. The most intense winds and heaviest rainfall

The eyewall of a cyclone contains the most intense winds and heaviest rainfall, surrounding the relatively calm eye. The eyewall is a ring of towering thunderstorms that generate the cyclone's maximum winds and most destructive forces. When the eyewall passes over an area, it typically causes the most severe damage during a cyclone event.

Correct Answer: B. Flood control, irrigation, and power generation on the Damodar river

The Damodar Valley Corporation (DVC) was established in 1948 modelled on the Tennessee Valley Authority of the USA, primarily for integrated development of the Damodar river valley including flood control, irrigation, and hydropower generation. The construction of a series of reservoirs on the Damodar and its tributaries significantly reduced the severe flooding that had historically earned the river the name 'Sorrow of Bengal.'

Correct Answer: B. Densely populated low-lying coastlines

The densely populated, low-lying coastlines surrounding the Bay of Bengal — particularly in Bangladesh, India's Odisha, West Bengal, and Andhra Pradesh — make North Indian Ocean cyclones disproportionately deadly compared to cyclones in other basins. Even relatively weaker cyclones can cause mass casualties when they strike these heavily populated areas with limited elevation. Storm surges sweeping across flat coastal plains with millions of inhabitants have repeatedly caused catastrophic losses.

Correct Answer: B. Waterborne diseases from contaminated floodwaters

Post-cyclone disease outbreaks primarily involve waterborne diseases such as cholera, typhoid, diarrhoea, and leptospirosis caused by contamination of drinking water sources by floodwaters mixed with sewage and rotting debris. After the 1999 Odisha cyclone and other major events, disease surveillance and provision of clean water were critical components of relief operations. Public health response is now an integral part of cyclone relief plans.

Correct Answer: B. IMD

IMD operates the Cyclone Warning Dissemination System (CWDS), which transmits cyclone alerts and warnings directly to coastal areas through a network of transmitters covering all cyclone-prone coastal districts. The system provides warnings even in areas with poor telecommunications infrastructure. CWDS is a critical component of India's early warning network, ensuring that fishermen and coastal communities receive timely alerts.

Correct Answer: B. Dense population, hard surfaces, and rapid runoff increase casualties

Urban flash floods are particularly dangerous because dense populations living in low-lying areas, extensive impervious surfaces that accelerate runoff, underground utility infrastructure, and lack of natural water absorption dramatically increase both the speed of flooding and the number of people at risk. In cities, people in basements, underpasses, and vehicles are especially vulnerable. Mumbai, Chennai, and Bengaluru have all experienced deadly urban flash floods.