The new environmental impact assessment (EIA) report for the Outer Ring Road (ORR) project, which will connect Navaikulam and Vizhinjam in Kerala, is poised to make it one of the most engineering-intensive highway projects in the state. The project features a network of tunnels, viaducts, and elevated stretches designed to reduce environmental damage and large-scale displacement.
Revised Alignment and Key Features
The National Highways Authority of India (NHAI) has preferred the revised alignment Option-3 in the report, which was assessed by TOI. This alignment proposes 17 tunnels and 50 viaducts across the 62.7-kilometer access-controlled highway corridor. The report describes this alignment as the most environmentally feasible among the three alternatives studied for the ambitious NH-866 project.
The public hearing by the Kerala State Pollution Control Board, based on the EIA report, is scheduled for June 11 at Devi Auditorium in Kattakada. According to an NHAI official, the Centre's approval is expected after the public hearing. "After obtaining environmental clearance from the Union Ministry of Environment, Forest and Climate Change, we will proceed with compensation payment and floating tender for construction," the official said.
Environmental and Engineering Considerations
As per the EIA report, tunnels have been proposed mainly in the undulating and ecologically sensitive midland regions to minimize extensive hill cutting, slope destabilization, and soil erosion. The report noted that conventional road construction through these stretches would require large-scale excavation and filling activities, increasing the risk of landslides and environmental degradation.
However, around 4,724 structures, mostly houses, are expected to be affected, while agricultural land, including rubber plantations and paddy fields, would be acquired for the project. Besides tunnels, the project includes six flyover-cum-viaduct structures, two major bridges, and 17 minor bridges. Several viaducts are proposed over low-lying areas, streams, and densely inhabited regions to reduce land acquisition and maintain natural drainage patterns.
Alignment Revisions and Impact Reduction
The EIA report, prepared by UltraTech for NHAI, stated that the engineering structures were incorporated after repeated alignment revisions aimed at avoiding thickly populated settlements, paddy fields, and water bodies. Balancing construction feasibility, social impact, and environmental concerns, the revised Option-3 alignment was deemed the best alternative by officials associated with the project.
The report said the selected alignment would require around 360 hectares, significantly lower than the other two options studied. Tree cutting has been reduced considerably under the revised alignment, with around 21,000 trees likely to be affected. The EIA report pointed out that the revised alignment avoids forest land and lies over 10 kilometers away from the Neyyar Wildlife Sanctuary, eliminating the need for wildlife clearance from the National Board for Wildlife.
Project Route
The highway begins from Navaikulam on NH-66 and terminates near Mukkola on the Vizhinjam bypass. This strategic route is expected to enhance connectivity and reduce travel time in the region.
