EIA report for ORR proposes 17 tunnels and 50 viaducts

T'puram: The new environmental impact assessment (EIA) report for the Outer Ring Road (ORR) project connecting Navaikulam and Vizhinjam is set to make it one of the most engineering-intensive highway projects in the state with a network of tunnels, viaducts and elevated stretches aimed at reducing environmental damage and large-scale displacement.National Highways Authority of India (NHAI) preferred revised alignment Option-3 in the report, assessed by TOI, which proposes 17 tunnels and 50 viaducts across the 62.7-km access-controlled highway corridor. The report describes the alignment as the most environmentally feasible among the three alternatives studied for the ambitious NH-866 project. Meanwhile, the public hearing by 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, Centre's approval is expected after the public hearing. "After obtaining environmental clearance from Union ministry of environment, forest and climate change, we will proceed with compensation payment and floating tender for construction," he said. As per the EIA report, tunnels have been proposed mainly in the undulating and ecologically sensitive midland regions to minimise extensive hill cutting, slope destabilisation 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.The EIA report prepared by UltraTech for NHAI said the engineering structures were incorporated after repeated alignment revisions aimed at avoiding thickly populated settlements, paddy fields and waterbodies. Balancing construction feasibility, social impact and environmental concerns, revised Option-3 alignment was the best alternative, said 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 10km away from Neyyar Wildlife Sanctuary, eliminating the need for wildlife clearance from National Board for Wildlife. The highway begins from Navaikulam on NH-66 and terminates near Mukkola on Vizhinjam bypass.