Context: The National Highways Authority of India released the first National Highways – Green Cover Index (NH-GCI) Annual Report (2025–26) to assess vegetation cover along India’s national highways.
The inaugural assessment evaluated nearly 30,000 km of National Highways across 24 states, using satellite data collected between July and December 2024.
According to the report, Assam recorded the highest highway green cover (53.16%), followed by Gujarat and Telangana, while Himachal Pradesh and Delhi registered the lowest green cover along their highway networks.
About the National Highways – Green Cover Index (NH-GCI)
The NH-GCI is a scientific framework developed to quantitatively measure the extent and density of vegetation along National Highways.
Key Features
- Scientific Measurement:
The index assesses roadside plantations and vegetation cover along highways using objective, technology-based indicators. - Collaboration with Space Agency:
NHAI developed the index through a three-year Memorandum of Understanding (MoU) with the National Remote Sensing Centre, which functions under the Indian Space Research Organisation. - Satellite-Based Monitoring:
High-resolution imagery from the Resourcesat-2 and Resourcesat-2A is used to detect chlorophyll presence, enabling accurate estimation of vegetation density along highway corridors. - Standardised Green Index:
The NH-GCI creates a consistent national benchmark for comparing green cover performance across states and highway stretches.
Significance
1. Monitoring Green Infrastructure
The index supports effective monitoring of the Green Highways Policy, which mandates that 1% of the total project cost of national highway projects be allocated for roadside plantation and landscaping.
2. Promoting Sustainable Transport Corridors
Vegetation along highways improves carbon sequestration, dust control, and micro-climatic regulation, making transport infrastructure more environmentally sustainable.
3. Technology-Driven Governance
The use of satellite imagery and remote sensing introduces data-driven environmental monitoring, ensuring transparency and periodic evaluation of plantation initiatives.
4. Climate and Biodiversity Benefits
Highway plantations can function as green corridors, supporting biodiversity, reducing soil erosion, and improving ecological connectivity.