Cat Tien National Park, already under attack from illegal logging, faces a risk of encroachment from hydroelectric projects. — VNA/VNS Photo Hoang Tuan

Dams, especially those built around the river's upper end, have worried experts and local residents alike due to their negative impact on the river, its basin, the environment and biodiversity.

Speaking at a workshop held in Dong Nai Province yesterday, Dr Vu Ngoc Long, from the Viet Nam River Network's southern office, said that ensuring the natural flow and balance of water volume in the upper regions of the river would be crucial to the development of the entire river basin.

"The lower part of Dong Nai River, key to food plants and industrial trees in both Dong Nai and Lam Dong provinces, is extremely vulnerable," he said.

Among the dams listed in the national power development strategy, power plant projects 6 and 6A will reclaim around 327ha of forest land in the Cat Tien National Park and its buffer zone.

Such projects have created increased concern related to impacts on biodiversity and the environment, according to experts, seeing as reservoirs will take up vast amounts of forestland in Dong Nai, Lam Dong and Binh Phuoc provinces.

However, the Duc Long Gia Lai Corporation has said that its projects would not negatively influence the volume of water or the park.

Nguyen Van Sy, chief consultant for Duc Long Gia Lai, said: "Reservoirs 6 and 6A will operate on a daily basis, allowing the retention and release of water within one day to minimise impacts on natural flow".

He added that the project would not occupy agricultural and residential land while not interfering with national park wild life.

Experts have noted that environmental impact assessments have not been entirely reliable.

"Environmental impact assessment (EIA) conducted by the investor itself have proven insufficient. They do not include information based on biodiversity changes, reservoir bed deposits, the management and protection of forests, changes to wild animal habitats, changes in water volume and erosion," said Le Anh Tuan, from the Can Tho University.

"The investor has failed to take into account potential risks and mistakes related to construction and operation," he noted.

Pham Thi Cam Nhung, from the WWF, said: "Noise from transporting construction materials, construction itself, mining and waste will create stress and reduce health among animals while opening a corridor for illegal logging and hunting."

According to Dr Dao Trong Tu, a senior consultant at the Viet Nam River Network, river water resources and forestland were national property related to public benefits necessitating thorough thought before action.

Tuan suggested not carrying out the projects due to the considerable risk and impact they pose.

(VNS)