FAQ – Irrawaddy Dolphins

Will construction noise and increased flows from the dam during the dry season have a negative impact on dolphins?
What are the biggest threats facing the dolphin population?

Excavation activities are isolated from the river by cofferdams. No underwater excavation is required or permitted at the powerhouse site, which is nearest the dolphin pool. Even with increased dry season flow through Sahong Channel during operation, this flow would not pass through the dolphin pool. Most of the inlet excavation and all of the downstream excavation will be undertaken in dry conditions, due to the temporary cofferdams being in place as noted above.

The real risks to dolphin survival in the Mekong have been well documented. They are: disturbance from tourism activities; capture in gill nets and other fishing gear; being struck by boats or their propellers and unexplained high mortality rates of calves and juveniles. In the long run, any species requires a minimum viable population size for survival; for a vertebrate species this means hundreds of individuals are necessary for long???term survival. In the absence of concerted intervention, it is predictable that dolphins will become extinct in this part of the Mekong.

Will underwater blasting related to the project harm the Irrawaddy dolphins nearby?
Will boat traffic over the dolphin pool increase during construction?

No underwater blasting is being carried out. The project EIA and Engineering Status Reports both clearly state that underwater blasting will not be permitted below the downstream cofferdam in order to protect the dolphin population.

The new access road and bridge that now link the project with the mainland eliminate the need to use barges to bring construction equipment to the site. As the people of Sahong and Sadam islands now have direct access to mainland, there has been a significant reduction in local boat traffic.