Thailand’s Department of Highways is considering ways to improve the road transportion link between Nakhon Ratchasima and Prachin Buri, by expanding the existing two lane, single carriageway that cuts through the Dong Phayayen-Khao Yai Forest Complex.

Running down a clearing roughly between Khao Yai and Thap Lan National Parks, Highway 304 is a shortcut between the Northeast and East through protected areas that stretch to the Cambodian border.

The existing road presents a hazard for crossing wildlife and some conservationists are concerned the envisaged six-lane highway upgrade will further fragment this World Heritage listed corridor.

At a recent consultation meeting attended by FREELAND staff, the Department of Highways presented proposals to mitigate the impact of the upgrade and possibly even improve safety for wildlife.

Five options are being considered:

1. Mountainous Highway Tunnel
2. Elevated Highway
3. Cut and Cover Tunnel or Shallow Tunnel
4. Wildlife Overpass and Underpass Crossing
5. Wildlife Overpass Crossing at Specific Locations

The effectiveness of each option in facilitating safe passage for wildlife appears to vary, as does the impact on the immediate environment and project costs.

The Department of Highways is consulting broadly with the National Park, Wildlife and Plant Conservation Department, NGOs, local community groups and university research departments. A final project proposal is expected to be presented to UNESCO this year.