New Delhi, Mar 9 (UNI) The National Highways Authority of India (NHAI) has released the first Annual Report on the National Highways Green Cover Index (NH-GCI) for 2025–26, introducing a satellite-based system to assess and monitor green cover along national highways across the country.
The initiative has been implemented in collaboration with the National Remote Sensing Centre (NRSC) of the Indian Space Research Organisation (ISRO) and aims to strengthen monitoring of plantations carried out under the Green Highways Policy.
According to the report, the NH-GCI uses high-resolution satellite imagery from Resourcesat-2 and Resourcesat-2A to estimate vegetation cover along highways. The system currently covers around 30,000 km of national highways in the operation and maintenance phase across 24 states, with monitoring conducted twice a year.
The Green Cover Index measures the percentage of land covered with vegetation along highway corridors, including plantations on the left and right sides of the road, as well as in the median wherever feasible. The analysis is conducted for every one-kilometre highway segment using the Normalized Difference Vegetation Index (NDVI) derived from satellite imagery.
The methodology was developed through pilot studies conducted on selected highway stretches in Rajasthan, Punjab and Odisha. A second phase of the pilot covered six national highways in Telangana, spanning over 1,120 km.
Validation of the results through field surveys and geo-tagged photographs showed about 90 per cent agreement between satellite-based estimates and ground observations, confirming the reliability of the remote-sensing approach for monitoring green cover along highways.
A dedicated web-based GIS portal on the Bhuvan platform has also been developed to provide interactive maps, kilometre-wise green cover statistics and automated reports for highway authorities.
A mobile application enables field surveyors to capture geo-tagged photographs to support ground verification.
Officials said the NH-GCI system will help NHAI track plantation performance, identify areas with low vegetation cover and improve management of green corridors along highways.
Future plans include using artificial intelligence and machine learning for automated vegetation classification, seasonal monitoring of plantations and integration with carbon estimation models to assess the environmental benefits of highway greening initiatives.
