I ran this column last year, but with the recent intense focus on dam breaching, I thought that I should change it up a little and run it again.

The statistics that I use were taken from 40 years of research by the Army Corps of Engineers and the Bonneville Power Administration, and compiled by retired Fish and Wildlife Biologist John McKern, who spent much of his 30-year career researching fish survival, and developing and implementing fish passage improvements at the Snake and Columbia river dams.