Urban Flooding
Context:
In recent times, urban areas in India have faced recurrent floods, causing immense harm to people’s lives and livelihoods. A journal published by the World Bank, sheds light on the growing flood risks in many cities, primarily due to urban expansion into flood-prone regions. It reveals that human settlements in flood-prone areas have more than doubled since 1985.
Relevance:
GS – 03 (Disaster Management, Environmental Pollution & Degradation)
Prelims:
Urban Flooding, Rainfall, Rural floods, Drainage System, Wetlands, Climate Change, Sewage and solid waste, Illegal Mining, Riverbank Erosion.
Mains Questions:
What are the main causes of Urban Flooding in India and discuss the measures in order to mitigate it. (250 words)
Urban Flooding:
- It is caused by heavy rainfall that overwhelms the capacity of drainage systems which leads to the inundation of land or property, particularly in more densely populated areas (like cities).
- It is also caused by unplanned urbanisation (catchments) that:
Causes:
- The large-scale encroachments without widening the natural drains, leading to decrease in the capacity of the natural drains resulting in flooding.
- The current climate change that has caused an increase in the frequency of short duration heavy localised rainfall leading to higher water run-off.
- Unplanned and sudden release of water from dams and lakes lead to floods in an urban area, without giving the public enough time to respond. (Example: The July 2023 flood in Delhi was magnified by 2 lakh cusecs of water discharged from the Hathnikund Barrage into the Yamuna River.)
- Illegal mining of river sand and quartzite for the commercial use deplete the natural bed of the rivers and lakes which causes soil erosion and reduces the water retention capacity of the waterbody increasing the speed and scale of water flow. (Example: Jaisamand Lake- Jodhpur, Cauvery river- Tamil Nadu)
Dimensions of the Article:
- India’s Vulnerability
- Disproportionate Impact on Informal Settlements
- Governance and Regulatory Gaps
India’s Vulnerability:
- India is the third largest contributor to global settlements in flood-prone regions, after China and the U.S.
- It also ranks third in terms of new settlements expanding into flood-prone areas between 1985 and 2015, after China and Vietnam.
- This data shows susceptibility of the country to future flood-related challenges, necessitating careful considerations.
Disproportionate Impact on Informal Settlements:
- Both experts, Raj Bhagat Palanichamy and Dr. Gautam Bhan, concur that the flood risks disproportionately affect residents of informal structures.
- These areas are often situated in low-lying, flood-prone regions and are inhabited by low-income communities.
- The geography of environmental risk aligns closely with the geography of informal, low-income housing.
Governance and Regulatory Gaps:
- One fundamental reason for the expansion of urban areas into flood-prone zones is the absence of robust governance processes.
- Existing environmental regulations are primarily applicable to major infrastructure projects, while medium- and small-scale developments within localities often evade such scrutiny.
- This disconnect between regulations and locality-specific flood risks exacerbates the problem. Moreover, regulatory violations are commonplace, leading to the construction of eco-tourism resorts on forest land and large structures on river floodplains.
The Way Forward:
- It is important to scientifically map the flood-prone areas for every city and urban governments should prioritize making housing in such regions flood-resilient, with a focus on protecting low-income housing.
- Innovative approaches like stilt houses used by certain communities along rivers can be made a practice.
- Implementation of sustainable urban planning that includes more natural green spaces, retention ponds and permeable surfaces to absorb and manage water should be inculcated at prone areas.
- The government should invest in expanding the drainage infrastructure which also includes regular maintenance.
- Establish a Early warning system to alert the people, especially the residents so that they can evacuate to safer places.
