What are the environmental implications of the reclamation of water bodies into urban land use ? Explain with examples.
Approach · directive: “what / explain”
What it asks · List the environmental consequences of filling lakes, ponds, wetlands and floodplains for construction, with Indian examples.
The question has 2 parts — answer each
- Explain the environmental implications of reclaiming water bodies for urban land use
- Illustrate each implication with Indian examples, and note what should be done
Open with · Cities often grow over their own lakes, tanks and marshes, turning flood buffers and recharge zones into impervious surfaces.
Cover
- Flooding: lost storage and blocked drains worsen urban floods, as in Chennai (2015), Mumbai (2005) and Srinagar (2014).
- Groundwater: paving recharge zones lowers water tables and dries wells and borewells, as in Bengaluru and Hyderabad, once cities of lakes and tanks.
- Biodiversity: habitat loss for fish, amphibians and migratory birds, and loss of natural water purification, as pressure on the East Kolkata Wetlands shows.
- Water quality: shrunken lakes receive sewage and effluent, causing eutrophication, foaming and even fires, as at Bengaluru's Bellandur lake.
- Climate: loss of evaporative cooling and green-blue space intensifies urban heat islands and weakens natural buffering of extreme rain.
- Coastal cities: reclaiming mangroves, creeks and marshes removes surge and flood buffers and adds subsidence risk.
- Remedies: Wetlands (Conservation and Management) Rules, 2017; notifying and mapping water bodies; restoring lakes and stormwater drains; and keeping blue-green space in city plans.
Close with · Water bodies are urban infrastructure; protecting and restoring them is cheaper than repairing floods, scarcity and pollution later.
Question: UPSC's CS (Main) 2021, GS Paper I — paper ↗. Approach: Minimalist IAS, checked 30 Sept 2026 (how we verify) — UPSC publishes no model answers. ·
Model answer · 225 words (UPSC limit 150) · Minimalist IAS
Cities have grown over their own lakes, tanks, wetlands and floodplains, turning flood buffers and recharge zones into impervious built-up land.
Environmental implications, with examples
- Urban flooding: lost storage and blocked natural drains turn heavy rain into floods — Chennai (2015), where building over the Pallikaranai marsh and floodplains worsened the deluge; Mumbai (2005); Srinagar (2014).
- Groundwater depletion: paving recharge zones lowers water tables and dries wells and borewells; Bengaluru and Hyderabad, once cities of lakes and tanks, now face water stress.
- Biodiversity loss: fish, amphibians and migratory birds lose habitat and natural purification ends; the East Kolkata Wetlands, which treat the city's sewage and support fisheries, face encroachment.
- Pollution: shrunken lakes become sinks for sewage and effluent, causing eutrophication, toxic foam and even fires, as at Bellandur lake in Bengaluru.
- Heat and climate: loss of evaporative cooling and blue-green space intensifies urban heat islands and removes a buffer against extreme rain.
- Coastal cities: reclaiming mangroves, creeks and salt marshes strips away storm-surge protection and adds subsidence risk, as in Mumbai.
Remedies
- Wetlands (Conservation and Management) Rules, 2017; mapping and notifying every water body; restoring lakes and stormwater drains; blue-green space as core infrastructure in master plans.
Water bodies are a city's free infrastructure for flood control, recharge and cooling; protecting them costs far less than repairing the floods, scarcity and pollution their loss brings.
Written by Minimalist IAS from facts checked at source (how we verify) — a little fuller than exam length, so every part of the question is covered; in the hall, keep the structure and trim the detail. UPSC publishes no model answers: compare your structure and coverage with this, then write your own.