Hydropower in the Columbia River: History of Fish Passage Development and Implications for the Mekong River

Hydropower development in the Columbia River Basin is an example of the challenges associated with trying to balance economic development and protection of native fish populations in a large river system.  While the importance of providing fish passage at dams was recognized early on, the success of fish passage has been mixed.  In addition, while common to focus on upstream passage, downstream passage is equally important and often more difficult to achieve.  Many modifications to structures and operations have been implemented to  improve fish passage success and survival.  At just the Federal Columbia/Snake River hydropower projects, about US$700 million dollars are spent annually on fish and wildlife mitigation measures.  The costs of implementing fish passage in the Columbia/Snake River system is widely known; however, the ongoing evaluations and flexibility to changes in structures and operations are not well known, yet are the means by which fish passage has improved over the years.  The Columbia/Snake River system is an example of the ongoing effort required to maintain sustainable hydropower.  A similar level of effort, and flexibility in structural and operational changes, will be needed in the Mekong River if sustainable hydropower is desired.