Summary: Pursuant to a congressional request, GAO evaluated the Army Corps of Engineers program for assisting fish migration past certain river dams, focusing on the Corps': (1) use of benefit and cost analysis and a computer model to estimate benefits; (2) consideration of other factors in its benefit estimates; and (3) consideration of the views of outside groups in deciding against constructing the bypasses.
GAO found that: (1) the Corps developed a computer model to estimate the number of additional adult fish that would return from the ocean if it constructed the proposed bypasses; (2) local agencies, tribes, and others noted model limitations, and researchers concluded that data limitations rendered the model inadequate for making precise economic benefit determinations; (3) the Corps acknowledged the model's data shortcomings and reliability problems; (4) the Corps did not recognize the proposed bypasses' potential for increased revenues through different electricity generation methods; (5) regulations did not require the Corps to consider noneconomic factors in constructing the bypasses, and it did not consider such potential benefits as the cultural and religious value of fish to Indian tribes; (6) the Corps did not adequately involve appropriate agencies in conducting planning studies as required; (7) the Corps could experience difficulty in establishing a mitigation objective, since comprehensive data on fish migrations prior to dam construction did not exist; and (8) the Corps' ability to base bypass construction decisions on cost-effectiveness may be limited, since information about bypass effectiveness was scarce and inconclusive.