Recent heavy rainfall in Kolkata brought the city to a halt. A single night saw 251 mm of rain, the highest since 1986. Streets flooded, public transport stopped, and businesses closed. This extreme event exposed critical gaps in urban planning and infrastructure. Indian cities face rising flood risks due to climate change, rapid urbanisation, and outdated drainage systems.
Extreme Rainfall and Climate Change
Climate change is increasing rainfall variability in Indian cities. Kolkata received 20 per cent of its yearly rain in just seven hours. Such intense downpours, known as cloudbursts, are becoming more frequent. These events overwhelm drainage systems designed for older, less extreme rainfall patterns.
Urbanisation and Loss of Natural Drainage
Rapid city growth has encroached on natural flood buffers like wetlands and floodplains. Since 2000, 39 per cent of new developments in India’s largest cities occurred on low-lying areas. In Kolkata, canals were paved, lakes filled, and marshlands built over. This reduces the ground’s ability to absorb water, causing faster and higher flood peaks.
Inadequate Infrastructure and Planning
Drainage networks in many cities are outdated and undersized. Solid waste often clogs sewers, worsening floods. Regulations to protect natural waterways are weak or poorly enforced. Kolkata’s drainage failed during the downpour combined with high tide, trapping water in the city. Similar vulnerabilities exist in many urban centres.
Priority Actions for Climate-Proofing Cities
Cities must invest in modern stormwater infrastructure. This includes wider drains, pumping stations, and retention basins to hold excess water temporarily. Restoring natural buffers such as wetlands and lakes is a cost-effective flood defence. Integrating blue-green infrastructure like parks and ponds helps absorb rainwater and reduces runoff. Development plans should restrict construction in flood-prone zones. These areas can be converted into parks or open spaces that safely flood when needed. Surat is an example of a city mapping flood risks and relocating infrastructure accordingly. Improved weather forecasting and flood warnings are essential. Early alerts can prevent casualties and property damage. Utilities must be crisis-proofed by insulating electrical cables or moving them underground to avoid electrocution risks during floods.
Financial and Governance Challenges
India spends only about 0.7 per cent of GDP on urban infrastructure, insufficient for growing climate risks. State governments can create resilience funds to support city projects. Urban local bodies need to enhance revenue through better tax collection and user charges to fund improvements. Kolkata’s flood event is a warning for Indian cities. With proper investment and planning, urban areas can better withstand extreme weather and reduce disruption.
Questions for UPSC:
- Taking example of Kolkata floods, critically discuss the impact of climate change on urban infrastructure and disaster management in Indian cities.
- Examine the role of urban planning and natural ecosystems in mitigating flood risks. How can blue-green infrastructure be integrated effectively?
- Discuss in the light of rapid urbanisation, the challenges and solutions for sustainable water management in Indian metropolitan areas.
- Analyse the financial and governance reforms necessary to enhance urban resilience against climate-induced disasters in India.
