National Highways Authority of India (NHAI) recently released the first-of-its-kind Annual Report on the National Highways Green Cover Index (NH-GCI) 2025–26. It aims to provide a quantitative assessment of the plantations along the National Highways (NHs).
What is National Highways Green Cover Index (NH-GCI)?
- It is a technology-driven metric released by the NHAI to scientifically assess and monitor vegetation along India’s national highway network.
- Developed in collaboration with ISRO’s National Remote Sensing Centre (NRSC)
- Objective: To provide a scientific and quantitative assessment of green cover within the Right of Way (RoW) along the NHs network by leveraging advanced space-based technologies.
- Background: The initiative has been taken under a three-year MoU that NHAI signed in January 2024 with the NRSC), Indian Space Research Organisation (ISRO).
Methodology
- The assessment is derived from chlorophyll content detected through high-resolution satellite sensors.
- Satellite Monitoring: Uses high-resolution Resourcesat-2/2A LISS-IV satellite imagery to detect chlorophyll content and measure vegetation density.
- Granular Assessment: Reports green cover as a percentage for every 1-kilometre segment within the Right of Way (RoW) on both sides of the highway.
- Classification: Highway stretches are categorised into four classes based on their density:
- Poor (0–25%)
- Moderate (25–50%)
- Good (50–75%) and
- Very Good (75–100%).
Recent Findings (2025-26 Report)
- In the first assessment cycle, approximately 30,000 kmof NHs spanning 24 States have been covered for the period July–December 2024.
- Subsequent annual cycles will track year-on-year changes to monitorprogressive improvements in green cove
| State Ranking | Green Cover % |
|---|---|
| Assam (Highest) | 53.16% |
| Gujarat | 46.91% |
| Telangana | 43.57% |
| Tamil Nadu | 42.38% |
| Himachal Pradesh (Lowest) | 13.50% |
| Delhi | 25.37% |
Significance
- This innovative approach offers a robust, reliable, cost-effective, and time-efficient mechanism for macro-level estimation of the green cover along the NHs.
- The findings will enable comparison, ranking, and targeted interventions for improved plantation management.
Operational Impact
- The index serves as a primary mechanism for environmental performance benchmarking.
- It allows the Ministry of Road Transport and Highways (MoRTH)to identify “canopy gaps” and target plantation interventions with higher precision.
- Future plans include using AI/MLfor automated vegetation loss alerts and integrating data with carbon sequestration models to support India’s Net Zero 2070