What Happened
- A joint study by the National Highways Authority of India (NHAI) and the Wildlife Institute of India (WII), titled "Landscapes Reconnected," documented 18 wildlife species using animal underpasses along the Delhi-Dehradun Expressway corridor.
- The study was conducted over 40 days along an 18–20 km stretch between Ganeshpur and Asharodi in Haridwar district, deploying 150 camera traps and 29 acoustic recorders, capturing 111,234 images.
- Prime Minister Narendra Modi is set to inaugurate the 210-km Delhi-Dehradun Expressway on April 14, 2026.
- The expressway features a 12-km elevated wildlife corridor over the Rajaji National Park — one of the most significant wildlife mitigation measures on any Indian highway.
- Sixty instances of elephants safely using the underpasses were recorded — demonstrating the effectiveness of the design for even the most space-sensitive megafauna.
Static Topic Bridges
Wildlife Mitigation Measures on National Highways — Eco-Bridges and Underpasses
As India expands its National Highway network under programmes like Bharatmala Pariyojana, linear infrastructure increasingly bisects wildlife habitats and forest corridors. This leads to habitat fragmentation — the division of continuous habitat into isolated patches — which reduces genetic diversity, disrupts animal movement, and increases human-wildlife conflict. Wildlife mitigation structures — underpasses, overpasses (eco-bridges), culverts, and elevated sections — are designed to maintain ecological connectivity across roads.
- Wildlife underpasses: Tunnels beneath highways that allow animals to cross without risk of road kill
- Eco-bridges / wildlife overpasses: Elevated green corridors above highways covered with native vegetation; India's first animal overpass was built on the Delhi-Mumbai Expressway (NH-48)
- The Delhi-Dehradun Expressway's 12-km elevated section over Rajaji National Park is the second such wildlife corridor on an Indian highway
- The Ganeshpur-Asharodi section has a network of 10.97 km of animal underpasses and elevated structures
- Noise management was found critical: sound-sensitive species (elephants, spotted deer) preferentially used quieter underpass segments
Connection to this news: The WII-NHAI study provides empirical evidence that properly designed and managed infrastructure can maintain wildlife connectivity — a critical finding for future highway environmental impact assessments (EIAs).
Delhi-Dehradun Expressway — Key Infrastructure and Ecological Context
The Delhi-Dehradun Expressway (National Highway 334B) is a 210-km, 6-lane (expandable to 8-lane) access-controlled corridor developed by NHAI at an estimated cost of approximately ₹12,000 crore. It connects Delhi to Dehradun (the winter capital of Uttarakhand), reducing travel time from 5 hours to 2.5 hours and distance from 250 km to 210 km. It passes through Delhi, Uttar Pradesh (Baghpat, Baraut, Shamli, Muzaffarnagar, Saharanpur), and Uttarakhand. The corridor runs through the Shivalik range, critical habitat for tigers, elephants, greater hornbills, and king cobras.
- Length: 210 km; Cost: ~₹12,000 crore (NHAI)
- 6-lane expandable to 8-lane; 16 entry-exit points; 5 railway overbridges
- 12-km elevated corridor over Rajaji National Park (the key wildlife protection zone)
- 6 animal underpasses + 2 elephant underpasses within the elevated section
- Rajaji National Park: Tiger Reserve spanning Uttarakhand's Haridwar, Dehradun, and Pauri districts; known elephant migration corridor
- Species documented in the study: Golden Jackal (most frequent), Nilgai, Sambar, Spotted Deer, Elephants, and 13 other species including carnivores, ungulates, pheasants, and primates
Connection to this news: The expressway demonstrates how mega-infrastructure projects can incorporate ecology — but only when wildlife passage is designed in from the start, not retrofitted later.
Habitat Fragmentation and the Importance of Wildlife Corridors
Habitat fragmentation is one of the primary drivers of biodiversity loss globally. When a continuous forest is cut by a highway, animal populations on either side become isolated. Over generations, this inbreeding and loss of genetic diversity weakens populations' ability to adapt. Wildlife corridors — strips of habitat connecting fragmented areas — allow animals to move between patches, interbreed, find food, and maintain viable population sizes. The concept is central to conservation biology and forms the basis for India's Project Tiger connectivity mandates.
- India's National Wildlife Action Plan (2017–31): Mandates identification and protection of wildlife corridors
- Project Tiger: 54 tiger reserves as of 2024; connectivity between reserves is essential for genetic diversity
- Elephant corridors: Wildlife Trust of India has mapped 101 elephant corridors in India; many are fragmented by roads and settlements
- The Shivalik-Terai landscape is one of India's most important tiger and elephant connectivity zones
- Environmental Impact Assessment (EIA) Notification, 2006: Requires EIA for all highway projects; wildlife corridors must be identified and mitigated
Connection to this news: The WII study's finding that 18 species — including elephants — are already using the underpasses validates the design approach and provides a replicable model for the 65,000+ km of new highways planned under Bharatmala.
Key Facts & Data
- Delhi-Dehradun Expressway: 210 km, 6-lane, ₹12,000 crore (NHAI), inaugurated April 14, 2026
- Route: Delhi → UP (Baghpat, Shamli, Muzaffarnagar, Saharanpur) → Dehradun (Uttarakhand)
- Travel time reduced: 5 hours → 2.5 hours
- 12-km elevated wildlife corridor over Rajaji National Park — second on any Indian highway
- Study "Landscapes Reconnected": 40 days, 150 camera traps, 29 acoustic recorders, 111,234 images
- 18 species documented using underpasses; Golden Jackal most frequent
- 60 recorded instances of elephants safely using the corridors
- Noise-sensitive species (elephants, spotted deer) use quieter underpass sections selectively
- India's first animal overpass: Delhi-Mumbai Expressway (NH-48), announced 2025