The estimated survival of Snake River juvenile fish migrating downstream
through the federal hydroelectric system is higher now than it was in 1964 — before three of the four Lower Snake River dams were built.
National Marine Fisheries Service researchers say smolt survival through
the hydrosystem during the mid-1960 was about 40 percent. Today, smolt
survival through eight dams is estimated to range from 40 to 60 percent
The survival trend — displayed in a bar graph …