Q Why is it in News ?
A Flood in Chennai has revived memories of the devastating Chennai floods of 2015, a collective trauma that its residents are yet to outlive.
Q What is role of climate change ?
- In August this year, as monsoon floods raged across the subcontinent, IPCC’s 6th Assessment Report (AR6) was published.
- The report noted the increasing frequency of heavy precipitation events since the 1950s and inferred that they were being driven by human-induced climate change.
- The climate crisis, is here.
- It has made extreme rainfall events more severe and unpredictable than ever before.
Q What is role of poor planning and encroachment ?
- In 2015, the National Green Tribunal in India formed a committee to report on the status of natural stormwater drains in Delhi.
- On inspection, out of the 201 “drains” recorded in 1976, 44 were found to be “missing.
- Geospatial imaging established that 376 km of natural storm drains — encroached on and paved over — had disappeared from Bengaluru.
- In both cases, these “missing” waterways were either encroached and built over or connected to sewage drains.
- Poor design and corruption significantly contribute to urban floods.
- By violating environmental laws and municipal bye-laws, open spaces, wetlands and floodplains have been mercilessly built over, making cities impermeable and hostile to rainwater.
Q What can be way forward ?
- We need to move away from land-centric urbanisation and recognise cities as waterscapes.
- We need to let urban rivers breathe by returning them to their floodplains.
- The entire urban watershed needs to heal, and for that to happen, we need less concrete and more democracy and science at the grassroots.
- Ever since concretisation became shorthand for urbanisation, rainfall in a changing climate no longer finds its way towards subterranean capillaries or surface water bodies.