e 6 Marks

What is the concept of green infrastructure?

Answer: Concept of Green Infrastructure

1. Definition

Green Infrastructure (GI) is a strategically planned and managed network of natural and semi-natural areas, features, and green spaces in urban and rural settings that deliver a wide range of ecosystem services while enhancing biodiversity, environmental quality, and human well-being.

Unlike traditional "grey infrastructure" (roads, pipes, buildings), green infrastructure uses vegetation, soils, and natural processes to manage water, create healthier urban environments, and provide multiple community benefits. It represents a cost-effective, resilient approach to urban challenges.

2. Key Components of Green Infrastructure

Component Description Primary Functions
Urban Parks & Gardens Public green spaces, community gardens, botanical gardens Recreation, air quality, carbon sequestration, habitat
Green Roofs Vegetation layers on building rooftops (extensive or intensive) Stormwater retention, insulation, urban heat mitigation
Green Walls/Facades Vertical gardens on building exteriors Air purification, cooling, aesthetic value, noise reduction
Urban Forests/Street Trees Tree cover along streets, in neighborhoods Shade, carbon storage, air filtration, property values
Bioswales Vegetated channels for stormwater conveyance Water filtration, flood control, pollutant removal
Rain Gardens Planted depressions collecting runoff Infiltration, groundwater recharge, water treatment
Permeable Pavements Porous surfaces allowing water infiltration Reduce runoff, recharge aquifers, reduce heat
Constructed Wetlands Engineered ecosystems mimicking natural wetlands Wastewater treatment, flood control, habitat
Green Corridors Linear green spaces connecting habitats Wildlife movement, recreation, ecological connectivity
Blue Infrastructure Water bodies - ponds, lakes, streams, rivers Flood management, cooling, biodiversity, amenity

3. Ecosystem Services Provided

A. Provisioning Services

  • Food Production: Urban agriculture, community gardens, rooftop farms
  • Fresh Water: Groundwater recharge, water purification
  • Raw Materials: Timber, fibers from managed green spaces

B. Regulating Services

  • Climate Regulation: Carbon sequestration, temperature moderation (reducing urban heat island by 2-8°C)
  • Water Regulation: Flood control, stormwater management (green roofs retain 40-90% rainfall)
  • Air Purification: Removal of pollutants, particulate matter, CO2
  • Noise Reduction: Vegetation buffers reduce noise levels by 5-10 dB
  • Pollination: Habitat for bees, butterflies supporting urban agriculture

C. Cultural Services

  • Recreation: Parks, trails, playgrounds for physical activity
  • Mental Health: Access to nature reduces stress, anxiety, depression
  • Aesthetic Value: Visual appeal, property value enhancement (10-20% increase)
  • Education: Environmental learning opportunities
  • Social Cohesion: Community gathering spaces, shared activities

D. Supporting Services

  • Habitat Provision: Refuges for urban wildlife, biodiversity corridors
  • Nutrient Cycling: Soil organisms decompose organic matter
  • Soil Formation: Vegetation contributes to healthy soil development

4. Planning Principles for Green Infrastructure

5. Benefits for Climate Resilience

Climate Adaptation: Green infrastructure is a key Nature-Based Solution (NbS) for urban climate resilience, addressing multiple climate risks simultaneously while providing co-benefits.

Climate Risk GI Solution Mechanism
Urban Heat Island Trees, green roofs, parks Evapotranspiration, shading (reduces temp by 2-8°C)
Flooding Bioswales, wetlands, permeable surfaces Infiltration, detention, natural drainage
Drought Rain gardens, water harvesting Groundwater recharge, water storage
Air Pollution Urban forests, green walls Pollutant absorption, particulate capture
Sea Level Rise Mangroves, coastal wetlands Wave attenuation, erosion control

6. Green Infrastructure in India

Policy Framework and Initiatives:
  • AMRUT Mission: Development of green spaces and parks in 500 cities
  • Smart Cities Mission: Green and blue infrastructure as key component
  • National Mission on Sustainable Habitat: Urban forestry and green cover
  • Development Control Regulations: Mandatory green area requirements in buildings
Indian Examples:
  • Chennai: Restoration of traditional water bodies (Eri system), stormwater drainage
  • Bengaluru: Lake restoration projects, urban forest initiatives
  • Nagpur: Large-scale urban plantation, green corridors
  • Surat: Riverfront development with green infrastructure
  • Mumbai: Mangrove conservation, Mithi River restoration

7. Challenges in Implementation

Conclusion

Green infrastructure represents a paradigm shift in urban planning, viewing nature not as a luxury but as essential infrastructure providing vital services. It offers cost-effective, resilient solutions to urban challenges including flooding, heat stress, air pollution, and biodiversity loss. As Indian cities face increasing climate risks and rapid urbanization, integrating green infrastructure into planning is crucial for creating sustainable, livable, and resilient urban environments. The concept aligns with India's commitment to sustainable development and climate action under the Paris Agreement.

Sources: Module 3 Notes | European Commission GI Strategy | Oxford Research Encyclopedia | B.Green Handbook | AMRUT Guidelines