Why this matters now

Urban floods (Chennai, Mumbai, Bengaluru, Hyderabad) are a recurring, topical GS-3 disaster — tested for causes and urban-resilience solutions.

Drainage
Key failure
Encroachment
Lost water bodies
Climate change
Intense rain
Sponge city
Resilience idea

Why Indian cities flood

  • Unplanned urbanisation and concretisation reducing natural drainage/infiltration;
  • Encroachment of wetlands, lakes and floodplains;
  • Inadequate, clogged and poorly maintained drainage;
  • Intense, erratic rainfall (cloudbursts) worsened by climate change;
  • Solid-waste mismanagement blocking drains.

Impact

Urban floods cause loss of life, displacement, damage to property and infrastructure, disease outbreaks, economic loss and traffic/utility paralysis — hitting the poor (in low-lying slums) hardest.

Building urban resilience

Solutions: restoring water bodies and natural drainage, sponge-city/blue-green infrastructure, scientific stormwater drainage, encroachment removal, early-warning and flood forecasting, resilient land-use planning, and waste management. Global frameworks like the Sendai Framework and CDRI guide resilient, climate-adaptive cities.

UPSC angle

Know urban-flood causes (unplanned urbanisation, encroached water bodies, poor drainage, intense rain, waste), the impact, and resilience solutions (sponge cities, blue-green infra, drainage, CDRI/Sendai).

Frequently asked questions

Why do Indian cities flood?

Due to unplanned urbanisation, encroachment of water bodies, inadequate drainage, intense rainfall and waste blocking drains.

What is a sponge city?

An urban design approach that absorbs, stores and reuses rainwater through blue-green infrastructure to reduce flooding.

How does climate change worsen urban floods?

By increasing the frequency and intensity of erratic, heavy rainfall events like cloudbursts.

How can cities build flood resilience?

By restoring water bodies and drainage, blue-green infrastructure, early warning and resilient land-use planning.